@11ty/eleventy - npm Package Compare versions

Comparing version 1.0.2 to 2.0.0

cmd.js

@@ -20,11 +20,3 @@ #!/usr/bin/env node
   const argv = require("minimist")(process.argv.slice(2), {
-    string: [
-      "input",
-      "output",
-      "formats",
-      "config",
-      "pathprefix",
-      "port",
-      "to",
-    ],
+    string: ["input", "output", "formats", "config", "pathprefix", "port", "to"],
     boolean: [
@@ -37,7 +29,8 @@ "quiet",
       "serve",
-      "passthroughall",
       "incremental",
+      "ignore-initial",
     ],
     default: {
       quiet: null,
+      "ignore-initial": false,
     },
@@ -61,6 +54,3 @@ unknown: function (unknownArgument) {
   process.on("rejectionHandled", (promise) => {
-    errorHandler.warn(
-      promise,
-      "A promise rejection was handled asynchronously"
-    );
+    errorHandler.warn(promise, "A promise rejection was handled asynchronously");
   });
@@ -74,6 +64,8 @@
     let elev = new Eleventy(argv.input, argv.output, {
+      source: "cli",
       // --quiet and --quiet=true both resolve to true
       quietMode: argv.quiet,
       configPath: argv.config,
-      source: "cli",
+      pathPrefix: argv.pathprefix,
+      runMode: argv.serve ? "serve" : argv.watch ? "watch" : "build",
     });
@@ -89,6 +81,5 @@
 
-    elev.setPathPrefix(argv.pathprefix);
     elev.setDryRun(argv.dryrun);
+    elev.setIgnoreInitial(argv["ignore-initial"]);
     elev.setIncrementalBuild(argv.incremental);
-    elev.setPassthroughAll(argv.passthroughall);
     elev.setFormats(argv.formats);
@@ -103,3 +94,3 @@
           if (argv.serve) {
-            let startBrowsersync = true;
+            let shouldStartServer = true;
             elev
@@ -109,7 +100,7 @@ .watch()
                 // Build failed but error message already displayed.
-                startBrowsersync = false;
+                shouldStartServer = false;
                 // A build error occurred and we aren’t going to --serve
               })
               .then(function () {
-                if (startBrowsersync) {
+                if (shouldStartServer) {
                   elev.serve(argv.port);
@@ -116,0 +107,0 @@ }

package.json

 {
   "name": "@11ty/eleventy",
-  "version": "1.0.2",
+  "version": "2.0.0",
   "description": "Transform a directory of templates into HTML.",
@@ -9,2 +9,3 @@ "publishConfig": {
   "main": "src/Eleventy.js",
+  "types": "src/index.d.ts",
   "bin": {
@@ -15,3 +16,3 @@ "eleventy": "./cmd.js"
   "engines": {
-    "node": ">=12"
+    "node": ">=14"
   },
@@ -66,5 +67,6 @@ "funding": {
     "environmentVariables": {},
-    "failFast": false,
+    "failFast": true,
     "files": [
-      "./test/*.js"
+      "./test/*.js",
+      "./test/_issues/**/*test.js"
     ],
@@ -82,24 +84,25 @@ "ignoredByWatcher": [
   "devDependencies": {
-    "@11ty/eleventy-plugin-syntaxhighlight": "^4.1.0",
+    "@11ty/eleventy-plugin-syntaxhighlight": "^4.2.0",
     "@11ty/eleventy-plugin-vue": "1.0.0-canary.8",
-    "@vue/server-renderer": "^3.2.37",
-    "ava": "^3.15.0",
-    "husky": "^8.0.1",
+    "@vue/server-renderer": "^3.2.47",
+    "ava": "^5.2.0",
+    "husky": "^8.0.3",
     "js-yaml": "^4.1.0",
-    "lint-staged": "^13.0.3",
+    "lint-staged": "^13.1.1",
     "markdown-it-emoji": "^2.0.2",
-    "marked": "^4.0.18",
+    "marked": "^4.2.12",
     "nyc": "^15.1.0",
-    "prettier": "^2.7.1",
-    "rimraf": "^3.0.2",
-    "sass": "^1.54.4",
-    "toml": "^3.0.0",
-    "vue": "^3.2.37"
+    "prettier": "^2.8.4",
+    "pretty": "^2.0.0",
+    "rimraf": "^4.1.2",
+    "sass": "^1.58.0",
+    "vue": "^3.2.47"
   },
   "dependencies": {
     "@11ty/dependency-tree": "^2.0.1",
+    "@11ty/eleventy-dev-server": "^1.0.3",
     "@11ty/eleventy-utils": "^1.0.1",
     "@iarna/toml": "^2.2.5",
     "@sindresorhus/slugify": "^1.1.2",
-    "browser-sync": "^2.27.10",
+    "bcp-47-normalize": "^1.1.1",
     "chokidar": "^3.5.3",
@@ -110,3 +113,3 @@ "cross-spawn": "^7.0.3",
     "ejs": "^3.1.8",
-    "fast-glob": "^3.2.11",
+    "fast-glob": "^3.2.12",
     "graceful-fs": "^4.2.10",
@@ -117,9 +120,13 @@ "gray-matter": "^4.0.3",
     "is-glob": "^4.0.3",
+    "iso-639-1": "^2.1.15",
     "kleur": "^4.1.5",
-    "liquidjs": "^9.40.0",
-    "lodash": "^4.17.21",
-    "luxon": "^2.5.0",
-    "markdown-it": "^12.3.2",
-    "minimist": "^1.2.6",
-    "moo": "^0.5.1",
+    "liquidjs": "^10.4.0",
+    "lodash.chunk": "^4.2.0",
+    "lodash.get": "^4.4.2",
+    "lodash.set": "^4.3.2",
+    "luxon": "^3.2.1",
+    "markdown-it": "^13.0.1",
+    "micromatch": "^4.0.5",
+    "minimist": "^1.2.7",
+    "moo": "^0.5.2",
     "multimatch": "^5.0.0",
@@ -131,8 +138,9 @@ "mustache": "^4.2.0",
     "please-upgrade-node": "^3.2.0",
-    "pretty": "^2.0.0",
+    "posthtml": "^0.16.6",
+    "posthtml-urls": "^1.0.0",
     "pug": "^3.0.2",
     "recursive-copy": "^2.0.14",
-    "semver": "^7.3.7",
+    "semver": "^7.3.8",
     "slugify": "^1.6.5"
   }
 }

README.md

@@ -1,8 +0,8 @@
-<p align="center"><img src="https://www.11ty.dev/img/logo-github.png" alt="eleventy Logo"></p>
+<p align="center"><img src="https://www.11ty.dev/img/logo-github.svg" width="200" height="200" alt="eleventy Logo"></p>
 
-# eleventy 🕚⚡️
+# eleventy 🕚⚡️🎈🐀
 
 A simpler static site generator. An alternative to Jekyll. Written in JavaScript. Transforms a directory of templates (of varying types) into HTML.
 
-Works with HTML, Markdown, Liquid, Nunjucks, Handlebars, Mustache, EJS, Haml, Pug, and JavaScript Template Literals.
+Works with HTML, Markdown, JavaScript, Liquid, Nunjucks, Handlebars, Mustache, EJS, Haml, and Pug.
 
@@ -9,0 +9,0 @@ ## ➡ [Documentation](https://www.11ty.dev/docs/)

src/BenchmarkGroup.js

@@ -95,2 +95,3 @@ const ConsoleLogger = require("./Util/ConsoleLogger");
       let percent = Math.round((totalForBenchmark * 100) / totalTimeSpent);
+      let callCount = bench.getTimesCalled();
 
@@ -100,3 +101,3 @@ let output = {
         percent: this.padNumber(percent, 3),
-        calls: this.padNumber(bench.getTimesCalled(), 5),
+        calls: this.padNumber(callCount, 5),
       };
@@ -113,3 +114,8 @@ let str = `Benchmark ${output.ms}ms ${output.percent}% ${output.calls}× (${label}) ${type}`;
 
-      if (totalForBenchmark.toFixed(0) > 0) {
+      // Opt out of logging if low count (1× or 2×) or 0ms / 1%
+      if (
+        totalForBenchmark.toFixed(0) > 1 || // more than 1ms
+        callCount > 2 || // more than 2×
+        percent > 1 // more than 1%
+      ) {
         debugBenchmark(str);
@@ -116,0 +122,0 @@ }

src/ComputedData.js

@@ -1,3 +0,3 @@
-const lodashGet = require("lodash/get");
-const lodashSet = require("lodash/set");
+const lodashGet = require("lodash.get");
+const lodashSet = require("lodash.set");
 
@@ -28,2 +28,3 @@ const ComputedDataQueue = require("./ComputedDataQueue");
       let fns = {};
+      // TODO bug? no access to non-universal config things?
       if (this.config) {
@@ -94,5 +95,5 @@ fns = this.config.javascriptFunctions;
     debug("Computed data order of execution: %o", order);
-
     for (let key of order) {
       let computed = lodashGet(this.computed, key);
+
       if (typeof computed === "function") {
@@ -99,0 +100,0 @@ let ret = await computed(data);

src/ComputedDataProxy.js

@@ -1,4 +0,4 @@
-const lodashSet = require("lodash/set");
-const lodashGet = require("lodash/get");
-const isPlainObject = require("./Util/IsPlainObject");
+const lodashSet = require("lodash.set");
+const lodashGet = require("lodash.get");
+const { isPlainObject } = require("@11ty/eleventy-utils");
 
@@ -20,3 +20,7 @@ /* Calculates computed data using Proxies */
   getProxyData(data, keyRef) {
+    // WARNING: SIDE EFFECTS
     // Set defaults for keys not already set on parent data
+
+    // TODO should make another effort to get rid of this,
+    // See the ProxyWrap util for more proxy handlers that will likely fix this
     let undefinedValue = "__11TY_UNDEFINED__";
@@ -23,0 +27,0 @@ if (this.computedKeys) {

src/ComputedDataTemplateString.js

@@ -1,2 +0,2 @@
-const lodashSet = require("lodash/set");
+const lodashSet = require("lodash.set");
 const debug = require("debug")("Eleventy:ComputedDataTemplateString");
@@ -41,3 +41,6 @@
     for (let split of splits) {
-      let varName = split.substr(0, split.indexOf(this.suffix));
+      let varName = split.slice(
+        0,
+        split.indexOf(this.suffix) < 0 ? 0 : split.indexOf(this.suffix)
+      );
       if (varName) {
@@ -44,0 +47,0 @@ vars.add(varName);

src/defaultConfig.js

@@ -5,6 +5,7 @@ const urlFilter = require("./Filters/Url");
 const slugifyFilter = require("./Filters/Slugify");
-const getCollectionItem = require("./Filters/GetCollectionItem");
+const getLocaleCollectionItem = require("./Filters/GetLocaleCollectionItem");
+const getCollectionItemIndex = require("./Filters/GetCollectionItemIndex");
 
 module.exports = function (config) {
-  let eleventyConfig = this;
+  let templateConfig = this;
 
@@ -14,21 +15,35 @@ config.addFilter("slug", slugFilter);
 
-  config.addFilter("url", function (url, pathPrefixOverride) {
-    let pathPrefix =
-      pathPrefixOverride || eleventyConfig.getConfig().pathPrefix;
+  // Add pathPrefix manually to a URL
+  config.addFilter("url", function addPathPrefix(url, pathPrefixOverride) {
+    let pathPrefix;
+    if (pathPrefixOverride && typeof pathPrefixOverride === "string") {
+      pathPrefix = pathPrefixOverride;
+    } else {
+      pathPrefix = templateConfig.getPathPrefix();
+    }
+
     return urlFilter.call(this, url, pathPrefix);
   });
-  config.addFilter("log", console.log);
 
+  config.addFilter("log", (input, ...messages) => {
+    console.log(input, ...messages);
+    return input;
+  });
+
   config.addFilter("serverlessUrl", serverlessUrlFilter);
 
-  config.addFilter("getCollectionItem", (collection, page) =>
-    getCollectionItem(collection, page)
-  );
-  config.addFilter("getPreviousCollectionItem", (collection, page) =>
-    getCollectionItem(collection, page, -1)
-  );
-  config.addFilter("getNextCollectionItem", (collection, page) =>
-    getCollectionItem(collection, page, 1)
-  );
+  config.addFilter("getCollectionItemIndex", function (collection, pageOverride) {
+    return getCollectionItemIndex.call(this, collection, pageOverride);
+  });
 
+  config.addFilter("getCollectionItem", function (collection, pageOverride, langCode) {
+    return getLocaleCollectionItem.call(this, config, collection, pageOverride, langCode, 0);
+  });
+  config.addFilter("getPreviousCollectionItem", function (collection, pageOverride, langCode) {
+    return getLocaleCollectionItem.call(this, config, collection, pageOverride, langCode, -1);
+  });
+  config.addFilter("getNextCollectionItem", function (collection, pageOverride, langCode) {
+    return getLocaleCollectionItem.call(this, config, collection, pageOverride, langCode, 1);
+  });
+
   return {
@@ -51,5 +66,11 @@ templateFormats: [
     htmlTemplateEngine: "liquid",
-    dataTemplateEngine: false, // change in 1.0
     htmlOutputSuffix: "-o",
-    jsDataFileSuffix: ".11tydata",
+
+    // Renamed from `jsDataFileSuffix` in 2.0 (and swapped to an Array)
+    // If you remove "" we won’t look for dir/dir.json or file.json
+    dataFileSuffixes: [".11tydata", ""],
+
+    // "index" will look for `directory/index.*` directory data files instead of `directory/directory.*`
+    dataFileDirBaseNameOverride: false,
+
     keys: {
@@ -56,0 +77,0 @@ package: "pkg",

src/Eleventy.js

@@ -15,7 +15,8 @@ const { TemplatePath } = require("@11ty/eleventy-utils");
 const ConsoleLogger = require("./Util/ConsoleLogger");
+const PathPrefixer = require("./Util/PathPrefixer");
 const TemplateConfig = require("./TemplateConfig");
+const FileSystemSearch = require("./FileSystemSearch");
 
-const templateCache = require("./TemplateCache");
 const simplePlural = require("./Util/Pluralize");
-const deleteRequireCache = require("./Util/DeleteRequireCache");
+const checkPassthroughCopyBehavior = require("./Util/PassthroughCopyBehaviorCheck");
 const debug = require("debug")("Eleventy");
@@ -48,2 +49,13 @@ const eventBus = require("./EventBus");
 
+    /**
+     * @member {String} - The top level directory the site pretends to reside in
+     * @default "/"
+     */
+    this.pathPrefix = options.pathPrefix || "/";
+
+    if (this.pathPrefix || this.pathPrefix === "") {
+      this.eleventyConfig.setPathPrefix(this.pathPrefix);
+    }
+
+    /* Programmatic API config */
     if (options.config && typeof options.config === "function") {
@@ -67,5 +79,22 @@ // TODO use return object here?
     /**
+     * @member {Boolean} - Running in serverless mode
+     * @default false
+     */
+    if ("isServerless" in options) {
+      this.isServerless = !!options.isServerless;
+    } else {
+      this.isServerless = !!process.env.AWS_LAMBDA_FUNCTION_NAME;
+    }
+
+    /**
+     * @member {String} - One of build, serve, or watch
+     * @default "build"
+     */
+    this.runMode = options.runMode || "build";
+
+    /**
      * @member {Object} - Initialize Eleventy environment variables
      * @default null
      */
+    // both this.isServerless and this.runMode need to be set before this
     this.env = this.getEnvironmentVariableValues();
@@ -139,2 +168,3 @@ this.initializeEnvironmentVariables(this.env);
     this.eleventyServe.config = this.config;
+    this.eleventyServe.eleventyConfig = this.eleventyConfig;
 
@@ -153,4 +183,10 @@ /** @member {String} - Holds the path to the input directory. */
     this.watchTargets.addAndMakeGlob(this.config.additionalWatchTargets);
-    this.watchTargets.watchJavaScriptDependencies =
-      this.config.watchJavaScriptDependencies;
+    this.watchTargets.watchJavaScriptDependencies = this.config.watchJavaScriptDependencies;
+
+    /** @member {Object} - tbd. */
+    this.fileSystemSearch = new FileSystemSearch();
+
+    this.isIncremental = false;
+    this.programmaticApiIncrementalFile = undefined;
+    this.isRunInitialBuild = true;
   }
@@ -186,9 +222,3 @@
   get outputDir() {
-    let dir = this.rawOutput || this.config.dir.output;
-    if (dir !== this._savedOutputDir) {
-      this.eleventyServe.setOutputDir(dir);
-    }
-    this._savedOutputDir = dir;
-
-    return dir;
+    return this.rawOutput || this.config.dir.output;
   }
@@ -218,9 +248,10 @@
   /**
-   * Updates the passthrough mode of Eleventy.
+   * Set whether or not to do an initial build
    *
    * @method
-   * @param {Boolean} isPassthroughAll - Shall Eleventy passthrough everything?
+   * @param {Boolean} ignoreInitialBuild - Shall Eleventy ignore the default initial build before watching in watch/serve mode?
+   * @default true
    */
-  setPassthroughAll(isPassthroughAll) {
-    this.isPassthroughAll = !!isPassthroughAll;
+  setIgnoreInitial(ignoreInitialBuild) {
+    this.isRunInitialBuild = !ignoreInitialBuild;
   }
@@ -260,12 +291,6 @@
     this.start = this.getNewTimestamp();
-    templateCache.clear();
+
     this.bench.reset();
     this.eleventyFiles.restart();
     this.extensionMap.reset();
-
-    // reload package.json values (if applicable)
-    // TODO only reset this if it changed
-    deleteRequireCache(TemplatePath.absolutePath("package.json"));
-
-    await this.init();
   }
@@ -295,5 +320,3 @@
     if (copyCount) {
-      slashRet.push(
-        `Copied ${copyCount} ${simplePlural(copyCount, "file", "files")}`
-      );
+      slashRet.push(`Copied ${copyCount} ${simplePlural(copyCount, "file", "files")}`);
     }
@@ -316,5 +339,3 @@
     if (writeCount >= 10) {
-      ret.push(
-        `(${((time * 1000) / writeCount).toFixed(1)}ms each, ${versionStr})`
-      );
+      ret.push(`(${((time * 1000) / writeCount).toFixed(1)}ms each, ${versionStr})`);
     } else {
@@ -324,8 +345,28 @@ ret.push(`(${versionStr})`);
 
-    let pathPrefix = this.config.pathPrefix;
-    if (pathPrefix && pathPrefix !== "/") {
-      return `Using pathPrefix: ${pathPrefix}\n${ret.join(" ")}`;
+    return ret.join(" ");
+  }
+
+  _cache(key, inst) {
+    if (!this._privateCaches) {
+      this._privateCaches = new Map();
     }
 
-    return ret.join(" ");
+    if (!("caches" in inst)) {
+      throw new Error("To use _cache you need a `caches` getter object");
+    }
+
+    // Restore from cache
+    if (this._privateCaches.has(key)) {
+      let c = this._privateCaches.get(key);
+      for (let cacheKey in c) {
+        inst[cacheKey] = c[cacheKey];
+      }
+    } else {
+      // Set cache
+      let c = {};
+      for (let cacheKey of inst.caches || []) {
+        c[cacheKey] = inst[cacheKey];
+      }
+      this._privateCaches.set(key, c);
+    }
   }
@@ -340,3 +381,5 @@
    */
-  async init() {
+  async init(options = {}) {
+    options = Object.assign({ viaConfigReset: false }, options);
+
     await this.config.events.emit("eleventy.config", this.eleventyConfig);
@@ -354,2 +397,15 @@
 
+    // eleventyServe is always available, even when not in --serve mode
+    this.eleventyServe.setOutputDir(this.outputDir);
+
+    // TODO
+    // this.eleventyServe.setWatcherOptions(this.getChokidarConfig());
+
+    this.templateData = new TemplateData(this.inputDir, this.eleventyConfig);
+    this.templateData.extensionMap = this.extensionMap;
+    if (this.env) {
+      this.templateData.environmentVariables = this.env;
+    }
+    this.templateData.setFileSystemSearch(this.fileSystemSearch);
+
     this.eleventyFiles = new EleventyFiles(
@@ -361,13 +417,15 @@ this.inputDir,
     );
-    this.eleventyFiles.setPassthroughAll(this.isPassthroughAll);
+    this.eleventyFiles.setFileSystemSearch(this.fileSystemSearch);
     this.eleventyFiles.setInput(this.inputDir, this.input);
+    this.eleventyFiles.setRunMode(this.runMode);
     this.eleventyFiles.extensionMap = this.extensionMap;
+    // This needs to be set before init or it’ll construct a new one
+    this.eleventyFiles.templateData = this.templateData;
     this.eleventyFiles.init();
 
-    this.templateData = new TemplateData(this.inputDir, this.eleventyConfig);
-    this.templateData.extensionMap = this.extensionMap;
-    if (this.env) {
-      this.templateData.environmentVariables = this.env;
+    if (checkPassthroughCopyBehavior(this.config, this.runMode)) {
+      this.eleventyServe.watchPassthroughCopy(
+        this.eleventyFiles.getGlobWatcherFilesForPassthroughCopy()
+      );
     }
-    this.eleventyFiles.templateData = this.templateData;
 
@@ -381,2 +439,7 @@ this.writer = new TemplateWriter(
     );
+
+    if (!options.viaConfigReset) {
+      this._cache("TemplateWriter", this.writer);
+    }
+
     this.writer.setInput(this.inputDir, this.input);
@@ -387,2 +450,5 @@ this.writer.logger = this.logger;
 
+    this.writer.setRunInitialBuild(this.isRunInitialBuild);
+    this.writer.setIncrementalBuild(this.isIncremental);
+
     let dirs = {
@@ -411,8 +477,3 @@ input: this.inputDir,
 
-    let data = this.templateData.cacheData();
-
     this.needsInit = false;
-
-    // …why does it return this
-    return data;
   }
@@ -422,12 +483,20 @@
   getEnvironmentVariableValues() {
+    let values = {
+      source: this.source,
+      runMode: this.runMode,
+    };
     let configPath = this.eleventyConfig.getLocalProjectConfigFile();
-    let absolutePathToConfig = TemplatePath.absolutePath(configPath);
-    // TODO(zachleat): if config is not in root (e.g. using --config=)
-    let root = TemplatePath.getDirFromFilePath(absolutePathToConfig);
+    if (configPath) {
+      let absolutePathToConfig = TemplatePath.absolutePath(configPath);
+      values.config = absolutePathToConfig;
 
-    return {
-      config: absolutePathToConfig,
-      root,
-      source: this.source,
-    };
+      // TODO(zachleat): if config is not in root (e.g. using --config=)
+      let root = TemplatePath.getDirFromFilePath(absolutePathToConfig);
+      values.root = root;
+    }
+
+    values.source = this.source;
+    values.isServerless = this.isServerless;
+
+    return values;
   }
@@ -444,9 +513,10 @@
 
-    process.env.ELEVENTY_SOURCE = this.source;
+    process.env.ELEVENTY_SOURCE = env.source;
+    process.env.ELEVENTY_RUN_MODE = env.runMode;
 
-    // TODO (@zachleat) this needs to be extensible. https://github.com/11ty/eleventy/issues/1957
-    // Note: when using --serve, ELEVENTY_SERVERLESS is set manually in Serverless.js
+    // https://github.com/11ty/eleventy/issues/1957
+    // Note: when using --serve, ELEVENTY_SERVERLESS is also set in Serverless.js
 
     // Careful here, setting to false will cast to string "false" which is truthy.
-    if (process.env.AWS_LAMBDA_FUNCTION_NAME) {
+    if (env.isServerless) {
       process.env.ELEVENTY_SERVERLESS = true;
@@ -547,2 +617,29 @@ debug("Setting process.env.ELEVENTY_SERVERLESS: %o", true);
   /**
+   * Updates the run mode of Eleventy.
+   *
+   * @method
+   * @param {String} runMode - One of "build", "watch", or "serve"
+   */
+  setRunMode(runMode) {
+    this.runMode = runMode;
+  }
+
+  /**
+   * Set the file that needs to be rendered/compiled/written for an incremental build.
+   * This method is part of the programmatic API and is not used internally.
+   *
+   * @method
+   * @param {String} incrementalFile - File path (added or modified in a project)
+   */
+  setIncrementalFile(incrementalFile) {
+    if (incrementalFile) {
+      // This is used for collections-friendly serverless mode.
+      this.setIgnoreInitial(true);
+      this.setIncrementalBuild(true);
+
+      this.programmaticApiIncrementalFile = incrementalFile;
+    }
+  }
+
+  /**
    * Reads the version of Eleventy.
@@ -594,2 +691,5 @@ *
 
+     --ignore-initial
+       Start without a build; build when files change. Works best with watch/serve/incremental.
+
      --formats=liquid,md
@@ -637,2 +737,3 @@ Whitelist only certain template types (default: \`*\`)
     this.eleventyServe.config = this.config;
+    this.eleventyServe.eleventyConfig = this.eleventyConfig;
 
@@ -653,2 +754,3 @@ // only use config quietMode if --quiet not set on CLI
   async _addFileToWatchQueue(changedFilePath) {
+    // Note: this is a sync event!
     eventBus.emit("eleventy.resourceModified", changedFilePath);
@@ -658,2 +760,24 @@ this.watchManager.addToPendingQueue(changedFilePath);
 
+  _shouldResetConfig() {
+    let configFilePaths = this.eleventyConfig.getLocalProjectConfigFiles();
+    let configFilesChanged = this.watchManager.hasQueuedFiles(configFilePaths);
+
+    if (configFilesChanged) {
+      return true;
+    }
+
+    for (const configFilePath of configFilePaths) {
+      // Any dependencies of the config file changed
+      let configFileDependencies = this.watchTargets.getDependenciesOf(configFilePath);
+
+      for (let dep of configFileDependencies) {
+        if (this.watchManager.hasQueuedFile(dep)) {
+          return true;
+        }
+      }
+    }
+
+    return false;
+  }
+
   /**
@@ -676,8 +800,8 @@ * tbd.
 
-    // reset and reload global configuration :O
-    if (
-      this.watchManager.hasQueuedFile(
-        this.eleventyConfig.getLocalProjectConfigFile()
-      )
-    ) {
+    // Clear `require` cache for all files that triggered the rebuild
+    this.watchTargets.clearRequireCacheFor(queue);
+
+    // reset and reload global configuration
+    let isResetConfig = this._shouldResetConfig();
+    if (isResetConfig) {
       this.resetConfig();
@@ -687,5 +811,4 @@ }
     await this.restart();
+    await this.init({ viaConfigReset: isResetConfig });
 
-    this.watchTargets.clearDependencyRequireCache();
-
     let incrementalFile = this.watchManager.getIncrementalFile();
@@ -696,5 +819,8 @@ if (incrementalFile) {
 
-    await this.write();
-    // let writeResult = await this.write();
-    // let hasError = !!writeResult.error;
+    let writeResults = await this.write();
+    let passthroughCopyResults;
+    let templateResults;
+    if (!writeResults.error) {
+      [passthroughCopyResults, ...templateResults] = writeResults;
+    }
 
@@ -717,13 +843,25 @@ this.writer.resetIncrementalFile();
         // TODO how to make this work with relative includes?
-        !TemplatePath.startsWithSubPath(
-          path,
-          this.eleventyFiles.getIncludesDir()
-        )
+        !TemplatePath.startsWithSubPath(path, this.eleventyFiles.getIncludesDir())
       );
     });
 
-    if (onlyCssChanges) {
-      this.eleventyServe.reload("*.css");
+    if (writeResults.error) {
+      this.eleventyServe.sendError({
+        error: writeResults.error,
+      });
     } else {
-      this.eleventyServe.reload();
+      let normalizedPathPrefix = PathPrefixer.normalizePathPrefix(this.config.pathPrefix);
+      await this.eleventyServe.reload({
+        files: this.watchManager.getActiveQueue(),
+        subtype: onlyCssChanges ? "css" : undefined,
+        build: {
+          templates: templateResults
+            .flat()
+            .filter((entry) => !!entry)
+            .map((entry) => {
+              entry.url = PathPrefixer.joinUrlParts(normalizedPathPrefix, entry.url);
+              return entry;
+            }),
+        },
+      });
     }
@@ -733,5 +871,8 @@
 
-    if (this.watchManager.getPendingQueueSize() > 0) {
+    let queueSize = this.watchManager.getPendingQueueSize();
+    if (queueSize > 0) {
       this.logger.log(
-        `You saved while Eleventy was running, let’s run again. (${this.watchManager.getPendingQueueSize()} remain)`
+        `You saved while Eleventy was running, let’s run again. (${queueSize} change${
+          queueSize !== 1 ? "s" : ""
+        })`
       );
@@ -763,11 +904,11 @@ await this._watch();
 
+    this.watchTargets.add(["./package.json"]);
     this.watchTargets.add(this.eleventyFiles.getGlobWatcherFiles());
+    this.watchTargets.add(this.eleventyFiles.getIgnoreFiles());
 
     // Watch the local project config file
-    this.watchTargets.add(this.eleventyConfig.getLocalProjectConfigFile());
+    this.watchTargets.add(this.eleventyConfig.getLocalProjectConfigFiles());
 
     // Template and Directory Data Files
-    this.watchTargets.add(
-      await this.eleventyFiles.getGlobWatcherTemplateDataFiles()
-    );
+    this.watchTargets.add(await this.eleventyFiles.getGlobWatcherTemplateDataFiles());
 
@@ -794,5 +935,5 @@ let benchmark = this.watcherBench.get(
 
-    let dataDir = this.templateData.getDataDir();
+    let dataDir = TemplatePath.stripLeadingDotSlash(this.templateData.getDataDir());
     function filterOutGlobalDataFiles(path) {
-      return !dataDir || path.indexOf(dataDir) === -1;
+      return !dataDir || !TemplatePath.stripLeadingDotSlash(path).startsWith(dataDir);
     }
@@ -806,3 +947,3 @@
     this.watchTargets.addDependencies(
-      this.eleventyConfig.getLocalProjectConfigFile(),
+      this.eleventyConfig.getLocalProjectConfigFiles(),
       filterOutGlobalDataFiles
@@ -812,6 +953,4 @@ );
     // Deps from Global Data (that aren’t in the global data directory, everything is watched there)
-    this.watchTargets.addDependencies(
-      this.templateData.getWatchPathCache(),
-      filterOutGlobalDataFiles
-    );
+    let globalDataDeps = this.templateData.getWatchPathCache();
+    this.watchTargets.addDependencies(globalDataDeps, filterOutGlobalDataFiles);
 
@@ -858,3 +997,3 @@ this.watchTargets.addDependencies(
   /**
-   * Start the watching of files.
+   * Start the watching of files
    *
@@ -907,2 +1046,3 @@ * @async
     let watchRun = async (path) => {
+      path = TemplatePath.normalize(path);
       try {
@@ -935,5 +1075,11 @@ this._addFileToWatchQueue(path);
       this.logger.forceLog(`File added: ${path}`);
+      this.fileSystemSearch.add(path);
       await watchRun(path);
     });
 
+    watcher.on("unlink", (path) => {
+      // this.logger.forceLog(`File removed: ${path}`);
+      this.fileSystemSearch.delete(path);
+    });
+
     process.on("SIGINT", () => this.stopWatch());
@@ -943,5 +1089,6 @@ }
   stopWatch() {
-    debug("Cleaning up chokidar and browsersync (if exists) instances.");
+    debug("Cleaning up chokidar and server instances, if they exist.");
     this.eleventyServe.close();
     this.watcher.close();
+
     process.exit();
@@ -955,4 +1102,6 @@ }
    */
-  serve(port) {
-    this.eleventyServe.serve(port);
+  async serve(port) {
+    // Port is optional and in this case likely via --port on the command line
+    // May defer to configuration API options `port` property
+    return this.eleventyServe.serve(port);
   }
@@ -1018,2 +1167,6 @@
 
+    if (this.programmaticApiIncrementalFile) {
+      this.writer.setIncrementalFile(this.programmaticApiIncrementalFile);
+    }
+
     let ret;
@@ -1025,2 +1178,6 @@ let hasError = false;
         inputDir: this.config.inputDir,
+        dir: this.config.dir,
+        runMode: this.runMode,
+        outputMode: to,
+        incremental: this.isIncremental,
       };
@@ -1045,2 +1202,10 @@ await this.config.events.emit("beforeBuild", eventsArg);
 
+      // Passing the processed output to the eleventy.after event is new in 2.0
+      let [passthroughCopyResults, ...templateResults] = ret;
+      if (to === "fs") {
+        eventsArg.results = templateResults.flat().filter((entry) => !!entry);
+      } else {
+        eventsArg.results = templateResults.filter((entry) => !!entry);
+      }
+
       if (to === "ndjson") {
@@ -1059,12 +1224,14 @@ // return a stream
       };
-      this.errorHandler.fatal(e, "Problem writing Eleventy templates");
+
+      // Issue #2405
+      if (this.source === "script") {
+        this.errorHandler.error(e, "Problem writing Eleventy templates");
+        throw e;
+      } else {
+        this.errorHandler.fatal(e, "Problem writing Eleventy templates");
+      }
     } finally {
       this.bench.finish();
       if (to === "fs") {
-        this.logger.message(
-          this.logFinished(),
-          "info",
-          hasError ? "red" : "green",
-          true
-        );
+        this.logger.message(this.logFinished(), "info", hasError ? "red" : "green", true);
       }
@@ -1086,1 +1253,4 @@ debug("Finished writing templates.");
 module.exports.EleventyRenderPlugin = require("./Plugins/RenderPlugin");
+module.exports.EleventyEdgePlugin = require("./Plugins/EdgePlugin");
+module.exports.EleventyI18nPlugin = require("./Plugins/I18nPlugin");
+module.exports.EleventyHtmlBasePlugin = require("./Plugins/HtmlBasePlugin");

src/EleventyErrorUtil.js

@@ -31,3 +31,8 @@ const TemplateContentPrematureUseError = require("./Errors/TemplateContentPrematureUseError");
 
-    return msg.substr(0, msg.indexOf(EleventyErrorUtil.prefix));
+    return msg.slice(
+      0,
+      msg.indexOf(EleventyErrorUtil.prefix) < 0
+        ? 0
+        : msg.indexOf(EleventyErrorUtil.prefix)
+    );
   }
@@ -71,3 +76,3 @@
           TemplateContentPrematureUseError) || // Liquid
-      e.message.indexOf("TemplateContentPrematureUseError") > -1
+      (e.message || "").indexOf("TemplateContentPrematureUseError") > -1
     ); // Nunjucks
@@ -74,0 +79,0 @@ }

src/EleventyExtensionMap.js

@@ -35,5 +35,3 @@ const { TemplatePath } = require("@11ty/eleventy-utils");
 
-    this.passthroughCopyKeys = this.unfilteredFormatKeys.filter(
-      (key) => !this.hasExtension(key)
-    );
+    this.passthroughCopyKeys = this.unfilteredFormatKeys.filter((key) => !this.hasExtension(key));
   }
@@ -156,12 +154,20 @@
     let dir = TemplatePath.convertToRecursiveGlobSync(inputDir);
-    let globs = [];
+    let extensions = [];
     for (let key of formatKeys) {
       if (this.hasExtension(key)) {
         for (let extension of this.getExtensionsFromKey(key)) {
-          globs.push(dir + "/*." + extension);
+          extensions.push(extension);
         }
       } else {
-        globs.push(dir + "/*." + key);
+        extensions.push(key);
       }
     }
+
+    let globs = [];
+    if (extensions.length === 1) {
+      globs.push(`${dir}/*.${extensions[0]}`);
+    } else if (extensions.length > 1) {
+      globs.push(`${dir}/*.{${extensions.join(",")}}`);
+    }
+
     return globs;
@@ -222,3 +228,6 @@ }
       if (path === extension || path.endsWith("." + extension)) {
-        return path.substr(0, path.length - 1 - extension.length);
+        return path.slice(
+          0,
+          path.length - 1 - extension.length < 0 ? 0 : path.length - 1 - extension.length
+        );
       }
@@ -225,0 +234,0 @@ }

src/EleventyFiles.js

 const fs = require("fs");
-const fastglob = require("fast-glob");
+
 const { TemplatePath } = require("@11ty/eleventy-utils");
@@ -10,2 +10,3 @@
 const EleventyBaseError = require("./EleventyBaseError");
+const checkPassthroughCopyBehavior = require("./Util/PassthroughCopyBehaviorCheck");
 
@@ -33,4 +34,2 @@ class EleventyFilesError extends EleventyBaseError {}
 
-    this.passthroughAll = false;
-
     this.formats = formats;
@@ -43,2 +42,6 @@ this.eleventyIgnoreContent = false;
 
+  setFileSystemSearch(fileSystemSearch) {
+    this.fileSystemSearch = fileSystemSearch;
+  }
+
   /* Overrides this.input and this.inputDir,
@@ -58,12 +61,6 @@ * Useful when input is a file and inputDir is not its direct parent */
   initConfig() {
-    this.includesDir = TemplatePath.join(
-      this.inputDir,
-      this.config.dir.includes
-    );
+    this.includesDir = TemplatePath.join(this.inputDir, this.config.dir.includes);
 
     if ("layouts" in this.config.dir) {
-      this.layoutsDir = TemplatePath.join(
-        this.inputDir,
-        this.config.dir.layouts
-      );
+      this.layoutsDir = TemplatePath.join(this.inputDir, this.config.dir.layouts);
     }
@@ -124,3 +121,3 @@ }
       config.ignores = new Set();
-      config.ignores.add("node_modules/**");
+      config.ignores.add("**/node_modules/**");
     }
@@ -144,6 +141,3 @@ this.config = config;
     if (!this._extensionMap) {
-      this._extensionMap = new EleventyExtensionMap(
-        this.formats,
-        this.eleventyConfig
-      );
+      this._extensionMap = new EleventyExtensionMap(this.formats, this.eleventyConfig);
       this._extensionMap.config = this.config;
@@ -154,4 +148,4 @@ }
 
-  setPassthroughAll(passthroughAll) {
-    this.passthroughAll = !!passthroughAll;
+  setRunMode(runMode) {
+    this.runMode = runMode;
   }
@@ -163,3 +157,5 @@
     mgr.setOutputDir(this.outputDir);
+    mgr.setRunMode(this.runMode);
     mgr.extensionMap = this.extensionMap;
+    mgr.setFileSystemSearch(this.fileSystemSearch);
     this.passthroughManager = mgr;
@@ -204,9 +200,3 @@ }
 
-    if (this.passthroughAll) {
-      this.normalizedTemplateGlobs = TemplateGlob.map([
-        TemplateGlob.normalizePath(this.input, "/**"),
-      ]);
-    } else {
-      this.normalizedTemplateGlobs = this.templateGlobs;
-    }
+    this.normalizedTemplateGlobs = this.templateGlobs;
   }
@@ -222,2 +212,6 @@
     }
+    // Placing the config ignores last here is important to the tests
+    for (let ignore of this.config.ignores) {
+      uniqueIgnores.add(TemplateGlob.normalizePath(this.localPathRoot || ".", ignore));
+    }
     return Array.from(uniqueIgnores);
@@ -240,5 +234,3 @@ }
 
-        ignores = ignores.concat(
-          EleventyFiles.normalizeIgnoreContent(dir, ignoreContent)
-        );
+        ignores = ignores.concat(EleventyFiles.normalizeIgnoreContent(dir, ignoreContent));
       }
@@ -267,17 +259,11 @@ }
             debug(">>>", line);
-            debug(
-              "Follow along at https://github.com/11ty/eleventy/issues/693 to track support."
-            );
+            debug("Follow along at https://github.com/11ty/eleventy/issues/693 to track support.");
           }
 
           // empty lines or comments get filtered out
-          return (
-            line.length > 0 && line.charAt(0) !== "#" && line.charAt(0) !== "!"
-          );
+          return line.length > 0 && line.charAt(0) !== "#" && line.charAt(0) !== "!";
         })
         .map((line) => {
           let path = TemplateGlob.normalizePath(dir, "/", line);
-          path = TemplatePath.addLeadingDotSlash(
-            TemplatePath.relativePath(path)
-          );
+          path = TemplatePath.addLeadingDotSlash(TemplatePath.relativePath(path));
 
@@ -305,39 +291,38 @@ try {
   getIgnores() {
-    let rootDirectory = this.localPathRoot || ".";
-    let files = [];
+    let files = new Set();
 
-    for (let ignore of this.config.ignores) {
-      files = files.concat(TemplateGlob.normalizePath(rootDirectory, ignore));
+    for (let ignore of EleventyFiles.getFileIgnores(this.getIgnoreFiles())) {
+      files.add(ignore);
     }
 
+    // testing API
+    if (this.eleventyIgnoreContent !== false) {
+      files.add(this.eleventyIgnoreContent);
+    }
+
+    // ignore output dir unless that would exclude all input
+    if (!TemplatePath.startsWithSubPath(this.inputDir, this.outputDir)) {
+      files.add(TemplateGlob.map(this.outputDir + "/**"));
+    }
+
+    return Array.from(files);
+  }
+
+  getIgnoreFiles() {
+    let ignoreFiles = [];
+    let rootDirectory = this.localPathRoot || ".";
+
     if (this.config.useGitIgnore) {
-      files = files.concat(
-        EleventyFiles.getFileIgnores([
-          TemplatePath.join(rootDirectory, ".gitignore"),
-        ])
-      );
+      ignoreFiles.push(TemplatePath.join(rootDirectory, ".gitignore"));
     }
 
-    if (this.eleventyIgnoreContent !== false) {
-      files = files.concat(this.eleventyIgnoreContent);
-    } else {
+    if (this.eleventyIgnoreContent === false) {
       let absoluteInputDir = TemplatePath.absolutePath(this.inputDir);
-      let eleventyIgnoreFiles = [
-        TemplatePath.join(rootDirectory, ".eleventyignore"),
-      ];
+      ignoreFiles.push(TemplatePath.join(rootDirectory, ".eleventyignore"));
       if (rootDirectory !== absoluteInputDir) {
-        eleventyIgnoreFiles.push(
-          TemplatePath.join(this.inputDir, ".eleventyignore")
-        );
+        ignoreFiles.push(TemplatePath.join(this.inputDir, ".eleventyignore"));
       }
-
-      files = files.concat(EleventyFiles.getFileIgnores(eleventyIgnoreFiles));
     }
 
-    // ignore output dir unless that would exclude all input
-    if (!TemplatePath.startsWithSubPath(this.inputDir, this.outputDir)) {
-      files = files.concat(TemplateGlob.map(this.outputDir + "/**"));
-    }
-
-    return files;
+    return ignoreFiles;
   }
@@ -364,5 +349,3 @@
     if (!this.pathCache) {
-      throw new Error(
-        "Watching requires `.getFiles()` to be called first in EleventyFiles"
-      );
+      throw new Error("Watching requires `.getFiles()` to be called first in EleventyFiles");
     }
@@ -380,6 +363,2 @@
   _globSearch() {
-    if (this._glob) {
-      return this._glob;
-    }
-
     let globs = this.getFileGlobs();
@@ -389,14 +368,9 @@
     debug("Searching for: %o", globs);
-
-    this._glob = fastglob(globs, {
-      caseSensitiveMatch: false,
-      dot: true,
+    return this.fileSystemSearch.search("templates", globs, {
       ignore: this.uniqueIgnores,
     });
-
-    return this._glob;
   }
 
   async getFiles() {
-    let bench = this.aggregateBench.get("Searching the file system");
+    let bench = this.aggregateBench.get("Searching the file system (templates)");
     bench.before();
@@ -407,17 +381,3 @@ let globResults = await this._globSearch();
 
-    // filter individual paths in the new config-specified extension
-    // where is this used?
-    if ("extensionMap" in this.config) {
-      let extensions = this.config.extensionMap;
-      if (Array.from(extensions).filter((entry) => !!entry.filter).length) {
-        paths = paths.filter(function (path) {
-          for (let entry of extensions) {
-            if (entry.filter && path.endsWith(`.${entry.extension}`)) {
-              return entry.filter(path);
-            }
-          }
-          return true;
-        });
-      }
-    }
+    // Note 2.0.0-canary.19 removed a `filter` option for custom template syntax here that was unpublished and unused.
 
@@ -430,2 +390,6 @@ this.pathCache = paths;
   isFullTemplateFile(paths, filePath) {
+    if (!filePath) {
+      return false;
+    }
+
     for (let path of paths) {
@@ -442,9 +406,19 @@ if (path === filePath) {
   getGlobWatcherFiles() {
-    // TODO is it better to tie the includes and data to specific file extensions or keep the **?
-    return this.validTemplateGlobs
-      .concat(this.passthroughGlobs)
-      .concat(this._getIncludesAndDataDirs());
+    // TODO improvement: tie the includes and data to specific file extensions (currently using `**`)
+    let directoryGlobs = this._getIncludesAndDataDirs();
+
+    if (checkPassthroughCopyBehavior(this.config, this.runMode)) {
+      return this.validTemplateGlobs.concat(directoryGlobs);
+    }
+
+    // Revert to old passthroughcopy copy files behavior
+    return this.validTemplateGlobs.concat(this.passthroughGlobs).concat(directoryGlobs);
   }
 
   /* For `eleventy --watch` */
+  getGlobWatcherFilesForPassthroughCopy() {
+    return this.passthroughGlobs;
+  }
+
+  /* For `eleventy --watch` */
   async getGlobWatcherTemplateDataFiles() {
@@ -459,9 +433,7 @@ let templateData = this.templateData;
     let globs = await this.templateData.getTemplateJavaScriptDataFileGlob();
-    let bench = this.aggregateBench.get("Searching the file system");
+    let bench = this.aggregateBench.get("Searching the file system (watching)");
     bench.before();
     let results = TemplatePath.addLeadingDotSlashArray(
-      await fastglob(globs, {
+      await this.fileSystemSearch.search("js-dependencies", globs, {
         ignore: ["**/node_modules/**"],
-        caseSensitiveMatch: false,
-        dot: true,
       })
@@ -476,5 +448,12 @@ );
     // convert to format without ! since they are passed in as a separate argument to glob watcher
-    return this.fileIgnores.map((ignore) =>
-      TemplatePath.stripLeadingDotSlash(ignore)
+    let entries = new Set(
+      this.fileIgnores.map((ignore) => TemplatePath.stripLeadingDotSlash(ignore))
     );
+
+    for (let ignore of this.config.watchIgnores) {
+      entries.add(TemplateGlob.normalizePath(this.localPathRoot || ".", ignore));
+    }
+
+    // de-duplicated
+    return Array.from(entries);
   }
@@ -481,0 +460,0 @@

src/EleventyServe.js

@@ -1,17 +0,32 @@
-const fs = require("fs");
-const path = require("path");
+const { TemplatePath } = require("@11ty/eleventy-utils");
 
-const { TemplatePath } = require("@11ty/eleventy-utils");
 const EleventyBaseError = require("./EleventyBaseError");
+const ConsoleLogger = require("./Util/ConsoleLogger");
+const PathPrefixer = require("./Util/PathPrefixer");
+const merge = require("./Util/Merge");
+const checkPassthroughCopyBehavior = require("./Util/PassthroughCopyBehaviorCheck");
+
 const debug = require("debug")("EleventyServe");
 
 class EleventyServeConfigError extends EleventyBaseError {}
+
+const DEFAULT_SERVER_OPTIONS = {
+  module: "@11ty/eleventy-dev-server",
+  port: 8080,
+  // pathPrefix: "/",
+  // setup: function() {},
+  // logger: { info: function() {}, error: function() {} }
+};
+
 class EleventyServe {
-  constructor() {}
+  constructor() {
+    this.logger = new ConsoleLogger(true);
+    this._initOptionsFetched = false;
+    this._aliases = undefined;
+    this._watchedFiles = new Set();
+  }
 
   get config() {
     if (!this._config) {
-      throw new EleventyServeConfigError(
-        "You need to set the config property on EleventyServe."
-      );
+      throw new EleventyServeConfigError("You need to set the config property on EleventyServe.");
     }
@@ -23,176 +38,220 @@
   set config(config) {
+    this._options = null;
     this._config = config;
   }
 
-  setOutputDir(outputDir) {
-    this.outputDir = outputDir;
+  setAliases(aliases) {
+    this._aliases = aliases;
+
+    if (this._server && "setAliases" in this._server) {
+      this._server.setAliases(aliases);
+    }
   }
 
-  getPathPrefix() {
-    let cfgPrefix = this.config.pathPrefix;
-    if (cfgPrefix) {
-      // add leading / (for browsersync), see #1454
-      // path.join uses \\ for Windows so we split and rejoin
-      return path.join("/", cfgPrefix).split(path.sep).join("/");
+  get eleventyConfig() {
+    if (!this._eleventyConfig) {
+      throw new EleventyServeConfigError(
+        "You need to set the eleventyConfig property on EleventyServe."
+      );
     }
-    return "/";
+
+    return this._eleventyConfig;
   }
 
-  getRedirectDir(dirName) {
-    return TemplatePath.join(this.outputDir, dirName);
-  }
-  getRedirectDirOverride() {
-    // has a pathPrefix, add a /index.html template to redirect to /pathPrefix/
-    if (this.getPathPrefix() !== "/") {
-      return "_eleventy_redirect";
+  set eleventyConfig(config) {
+    this._eleventyConfig = config;
+    if (checkPassthroughCopyBehavior(this._eleventyConfig.userConfig, "serve")) {
+      this._eleventyConfig.userConfig.events.on("eleventy.passthrough", ({ map }) => {
+        // for-free passthrough copy
+        this.setAliases(map);
+      });
     }
   }
 
-  getRedirectFilename(dirName) {
-    return TemplatePath.join(this.getRedirectDir(dirName), "index.html");
+  async setOutputDir(outputDir) {
+    // TODO check if this is different and if so, restart server (if already running)
+    // This applies if you change the output directory in your config file during watch/serve
+    this.outputDir = outputDir;
   }
 
-  getOptions(port) {
-    let pathPrefix = this.getPathPrefix();
+  getServerModule(name) {
+    try {
+      if (!name || name === DEFAULT_SERVER_OPTIONS.module) {
+        return require(DEFAULT_SERVER_OPTIONS.module);
+      }
 
-    // TODO customize this in Configuration API?
-    let serverConfig = {
-      baseDir: this.outputDir,
-    };
+      // Look for peer dep in local project
+      let projectNodeModulesPath = TemplatePath.absolutePath("./node_modules/");
+      let serverPath = TemplatePath.absolutePath(projectNodeModulesPath, name);
 
-    let redirectDirName = this.getRedirectDirOverride();
-    // has a pathPrefix, add a /index.html template to redirect to /pathPrefix/
-    if (redirectDirName) {
-      serverConfig.baseDir = this.getRedirectDir(redirectDirName);
-      serverConfig.routes = {};
-      serverConfig.routes[pathPrefix] = this.outputDir;
+      // No references outside of the project node_modules are allowed
+      if (!serverPath.startsWith(projectNodeModulesPath)) {
+        throw new Error("Invalid node_modules name for Eleventy server instance, received:" + name);
+      }
 
-      // if has a savedPathPrefix, use the /savedPathPrefix/index.html template to redirect to /pathPrefix/
-      if (this.savedPathPrefix) {
-        serverConfig.routes[this.savedPathPrefix] = TemplatePath.join(
-          this.outputDir,
-          this.savedPathPrefix
+      let module = require(serverPath);
+
+      if (!("getServer" in module)) {
+        throw new Error(
+          `Eleventy server module requires a \`getServer\` static method. Could not find one on module: \`${name}\``
         );
       }
+
+      let serverPackageJsonPath = TemplatePath.absolutePath(serverPath, "package.json");
+
+      let serverPackageJson = require(serverPackageJsonPath);
+      if (serverPackageJson["11ty"] && serverPackageJson["11ty"].compatibility) {
+        try {
+          this.eleventyConfig.userConfig.versionCheck(serverPackageJson["11ty"].compatibility);
+        } catch (e) {
+          this.logger.warn(`Warning: \`${name}\` Plugin Compatibility: ${e.message}`);
+        }
+      }
+
+      return module;
+    } catch (e) {
+      this.logger.error(
+        "There was an error with your custom Eleventy server. We’re using the default server instead.\n" +
+          e.message
+      );
+      debug("Eleventy server error %o", e);
+      return require(DEFAULT_SERVER_OPTIONS.module);
     }
+  }
 
-    return Object.assign(
+  get options() {
+    if (this._options) {
+      return this._options;
+    }
+
+    this._options = Object.assign(
       {
-        server: serverConfig,
-        port: port || 8080,
-        ignore: ["node_modules"],
-        watch: false,
-        open: false,
-        notify: false,
-        ui: false, // Default changed in 1.0
-        ghostMode: false, // Default changed in 1.0
-        index: "index.html",
+        pathPrefix: PathPrefixer.normalizePathPrefix(this.config.pathPrefix),
+        logger: this.logger,
       },
-      this.config.browserSyncConfig
+      DEFAULT_SERVER_OPTIONS,
+      this.config.serverOptions
     );
+
+    // TODO improve by sorting keys here
+    this._savedConfigOptions = JSON.stringify(this.config.serverOptions);
+
+    if (!this._initOptionsFetched && this.getSetupCallback()) {
+      throw new Error(
+        "Init options have not yet been fetched in the setup callback. This probably means that `init()` has not yet been called."
+      );
+    }
+
+    return this._options;
   }
 
-  cleanupRedirect(dirName) {
-    if (dirName && dirName !== "/") {
-      let savedPathFilename = this.getRedirectFilename(dirName);
+  get server() {
+    if (this._server) {
+      return this._server;
+    }
 
-      setTimeout(function () {
-        if (!fs.existsSync(savedPathFilename)) {
-          debug(`Cleanup redirect: Could not find ${savedPathFilename}`);
-          return;
-        }
+    let serverModule = this.getServerModule(this.options.module);
 
-        let savedPathContent = fs.readFileSync(savedPathFilename, "utf8");
-        if (
-          savedPathContent.indexOf("Browsersync pathPrefix Redirect") === -1
-        ) {
-          debug(
-            `Cleanup redirect: Found ${savedPathFilename} but it wasn’t an eleventy redirect.`
-          );
-          return;
-        }
+    // Static method `getServer` was already checked in `getServerModule`
+    this._server = serverModule.getServer("eleventy-server", this.outputDir, this.options);
 
-        fs.unlink(savedPathFilename, (err) => {
-          if (!err) {
-            debug(`Cleanup redirect: Deleted ${savedPathFilename}`);
-          }
-        });
-      }, 2000);
-    }
+    this.setAliases(this._aliases);
+
+    return this._server;
   }
 
-  serveRedirect(dirName) {
-    fs.mkdirSync(this.getRedirectDir(dirName), {
-      recursive: true,
-    });
-    fs.writeFileSync(
-      this.getRedirectFilename(dirName),
-      `<!doctype html>
-  <meta http-equiv="refresh" content="0; url=${this.config.pathPrefix}">
-  <title>Browsersync pathPrefix Redirect</title>
-  <a href="${this.config.pathPrefix}">Go to ${this.config.pathPrefix}</a>`
-    );
+  set server(val) {
+    this._server = val;
   }
 
-  serve(port) {
-    // Only load on serve—this is pretty expensive
-    // We use a string module name and try/catch here to hide this from the zisi and esbuild serverless bundlers
-    let server;
-    // eslint-disable-next-line no-useless-catch
-    try {
-      let moduleName = "browser-sync";
-      server = require(moduleName);
-    } catch (e) {
-      throw e;
+  getSetupCallback() {
+    let setupCallback = this.config.serverOptions.setup;
+    if (setupCallback && typeof setupCallback === "function") {
+      return setupCallback;
     }
+  }
 
-    this.server = server.create("eleventy-server");
+  async init() {
+    if (!this._initPromise) {
+      this._initPromise = new Promise(async (resolve) => {
+        let setupCallback = this.getSetupCallback();
+        if (setupCallback) {
+          let opts = await setupCallback();
+          this._initOptionsFetched = true;
 
-    let pathPrefix = this.getPathPrefix();
+          if (opts) {
+            merge(this.options, opts);
+          }
+        }
 
-    if (this.savedPathPrefix && pathPrefix !== this.savedPathPrefix) {
-      let redirectFilename = this.getRedirectFilename(this.savedPathPrefix);
-      if (!fs.existsSync(redirectFilename)) {
-        debug(
-          `Redirecting BrowserSync from ${this.savedPathPrefix} to ${pathPrefix}`
-        );
-        this.serveRedirect(this.savedPathPrefix);
-      } else {
-        debug(
-          `Config updated with a new pathPrefix. Tried to set up a transparent redirect but found a template already existing at ${redirectFilename}. You’ll have to navigate manually.`
-        );
-      }
+        resolve();
+      });
     }
 
-    let redirectDirName = this.getRedirectDirOverride();
-    // has a pathPrefix, add a /index.html template to redirect to /pathPrefix/
-    if (redirectDirName) {
-      this.serveRedirect(redirectDirName);
+    return this._initPromise;
+  }
+
+  // Port comes in here from --port on the command line
+  async serve(port) {
+    this._commandLinePort = port;
+
+    await this.init();
+
+    this.server.serve(port || this.options.port);
+  }
+
+  async close() {
+    if (this._server) {
+      await this.server.close();
+
+      this.server = undefined;
     }
+  }
 
-    this.cleanupRedirect(this.savedPathPrefix);
+  async sendError({ error }) {
+    if (this._server) {
+      await this.server.sendError({
+        error,
+      });
+    }
+  }
 
-    let options = this.getOptions(port);
-    this.server.init(options);
+  // Restart the server entirely
+  // We don’t want to use a native `restart` method (e.g. restart() in Vite) so that
+  // we can correctly handle a `module` property change (changing the server type)
+  async restart() {
+    await this.close();
 
-    // this needs to happen after `.getOptions`
-    this.savedPathPrefix = pathPrefix;
+    // saved --port in `serve()`
+    await this.serve(this._commandLinePort);
+
+    // rewatch the saved watched files (passthrough copy)
+    if ("watchFiles" in this.server) {
+      this.server.watchFiles(this._watchedFiles);
+    }
   }
 
-  close() {
-    if (this.server) {
-      this.server.exit();
+  // checkPassthroughCopyBehavior check is called upstream in Eleventy.js
+  // TODO globs are not removed from watcher
+  watchPassthroughCopy(globs) {
+    this._watchedFiles = globs;
+
+    if ("watchFiles" in this.server) {
+      this.server.watchFiles(globs);
     }
   }
 
-  /* filesToReload is optional */
-  reload(filesToReload) {
-    if (this.server) {
-      if (this.getPathPrefix() !== this.savedPathPrefix) {
-        this.server.exit();
-        this.serve();
-      } else {
-        this.server.reload(filesToReload);
-      }
+  // Live reload the server
+  async reload(reloadEvent = {}) {
+    if (!this._server) {
+      return;
     }
+
+    // Restart the server if the options have changed
+    if (JSON.stringify(this.config.serverOptions) !== this._savedConfigOptions) {
+      debug("Server options changed, we’re restarting the server");
+      await this.restart();
+    } else {
+      await this.server.reload(reloadEvent);
+    }
   }
@@ -199,0 +258,0 @@ }

src/EleventyWatch.js

 const { TemplatePath } = require("@11ty/eleventy-utils");
+const PathNormalizer = require("./Util/PathNormalizer.js");
 
@@ -32,7 +33,7 @@ /* Decides when to watch and in what mode to watch
   getIncrementalFile() {
-    if (!this.isActive || !this.incremental || this.activeQueue.length === 0) {
-      return false;
+    if (this.incremental) {
+      return this.activeQueue.length ? this.activeQueue[0] : false;
     }
 
-    return this.activeQueue[0];
+    return false;
   }
@@ -66,4 +67,3 @@
     return (
-      this.activeQueue.length > 0 &&
-      this.activeQueue.length === this._queueMatches(file).length
+      this.activeQueue.length > 0 && this.activeQueue.length === this._queueMatches(file).length
     );
@@ -73,5 +73,17 @@ }
   hasQueuedFile(file) {
-    return this._queueMatches(file).length > 0;
+    if (file) {
+      return this._queueMatches(file).length > 0;
+    }
+    return false;
   }
 
+  hasQueuedFiles(files) {
+    for (const file of files) {
+      if (this.hasQueuedFile(file)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
   get pendingQueue() {
@@ -90,3 +102,3 @@ if (!this._queue) {
     if (path) {
-      path = TemplatePath.addLeadingDotSlash(path);
+      path = PathNormalizer.normalizeSeperator(TemplatePath.addLeadingDotSlash(path));
       this.pendingQueue.push(path);
@@ -93,0 +105,0 @@ }

src/EleventyWatchTargets.js

@@ -1,5 +0,6 @@
-const dependencyTree = require("@11ty/dependency-tree");
 const { TemplatePath } = require("@11ty/eleventy-utils");
+const { DepGraph } = require("dependency-graph");
 
 const deleteRequireCache = require("./Util/DeleteRequireCache");
+const JavaScriptDependencies = require("./Util/JavaScriptDependencies");
 
@@ -12,2 +13,4 @@ class EleventyWatchTargets {
     this._watchJavaScriptDependencies = true;
+
+    this.graph = new DepGraph();
   }
@@ -27,12 +30,2 @@
 
-  _normalizeTargets(targets) {
-    if (!targets) {
-      return [];
-    } else if (Array.isArray(targets)) {
-      return targets;
-    }
-
-    return [targets];
-  }
-
   reset() {
@@ -46,2 +39,25 @@ this.newTargets = new Set();
 
+  addToDependencyGraph(parent, deps) {
+    if (!this.graph.hasNode(parent)) {
+      this.graph.addNode(parent);
+    }
+    for (let dep of deps) {
+      if (!this.graph.hasNode(dep)) {
+        this.graph.addNode(dep);
+      }
+      this.graph.addDependency(parent, dep);
+    }
+  }
+
+  uses(parent, dep) {
+    return this.getDependenciesOf(parent).includes(dep);
+  }
+
+  getDependenciesOf(parent) {
+    if (!this.graph.hasNode(parent)) {
+      return [];
+    }
+    return this.graph.dependenciesOf(parent);
+  }
+
   addRaw(targets, isDependency) {
@@ -62,15 +78,27 @@ for (let target of targets) {
 
+  static normalize(targets) {
+    if (!targets) {
+      return [];
+    } else if (Array.isArray(targets)) {
+      return targets;
+    }
+
+    return [targets];
+  }
+
   // add only a target
   add(targets) {
-    targets = this._normalizeTargets(targets);
-    this.addRaw(targets);
+    this.addRaw(EleventyWatchTargets.normalize(targets));
   }
 
-  addAndMakeGlob(targets) {
-    targets = this._normalizeTargets(targets).map((entry) =>
+  static normalizeToGlobs(targets) {
+    return EleventyWatchTargets.normalize(targets).map((entry) =>
       TemplatePath.convertToRecursiveGlobSync(entry)
     );
-    this.addRaw(targets);
   }
 
+  addAndMakeGlob(targets) {
+    this.addRaw(EleventyWatchTargets.normalizeToGlobs(targets));
+  }
+
   // add only a target’s dependencies
@@ -82,4 +110,4 @@ addDependencies(targets, filterCallback) {
 
-    targets = this._normalizeTargets(targets);
-    let deps = this.getJavaScriptDependenciesFromList(targets);
+    targets = EleventyWatchTargets.normalize(targets);
+    let deps = JavaScriptDependencies.getDependencies(targets);
     if (filterCallback) {
@@ -89,2 +117,5 @@ deps = deps.filter(filterCallback);
 
+    for (let target of targets) {
+      this.addToDependencyGraph(target, deps);
+    }
     this.addRaw(deps, true);
@@ -97,24 +128,12 @@ }
 
-  getJavaScriptDependenciesFromList(files = []) {
-    let depSet = new Set();
-    files
-      .filter((file) => file.endsWith(".js") || file.endsWith(".cjs")) // TODO does this need to work with aliasing? what other JS extensions will have deps?
-      .forEach((file) => {
-        dependencyTree(file, { allowNotFound: true })
-          .map((dependency) => {
-            return TemplatePath.addLeadingDotSlash(
-              TemplatePath.relativePath(dependency)
-            );
-          })
-          .forEach((dependency) => {
-            depSet.add(dependency);
-          });
-      });
+  clearRequireCacheFor(filePathArray) {
+    for (const filePath of filePathArray) {
+      deleteRequireCache(filePath);
 
-    return Array.from(depSet);
-  }
-
-  clearDependencyRequireCache() {
-    for (let path of this.dependencies) {
-      deleteRequireCache(TemplatePath.absolutePath(path));
+      // Any dependencies of the config file changed
+      let fileDeps = this.getDependenciesOf(filePath);
+      for (let dep of fileDeps) {
+        // Delete from require cache so that updates to the module are re-required
+        deleteRequireCache(dep);
+      }
     }
@@ -121,0 +140,0 @@ }

src/Engines/Custom.js

 const TemplateEngine = require("./TemplateEngine");
 const getJavaScriptData = require("../Util/GetJavaScriptData");
+const eventBus = require("../EventBus.js");
 
+let lastModifiedFile = undefined;
+eventBus.on("eleventy.resourceModified", (path) => {
+  lastModifiedFile = path;
+});
+
 class CustomEngine extends TemplateEngine {
@@ -24,2 +30,3 @@ constructor(name, dirs, config) {
     if ("extensionMap" in this.config) {
+      // Iterates over only the user config `addExtension` entries
       for (let entry of this.config.extensionMap) {
@@ -41,2 +48,5 @@ if (entry.key.toLowerCase() === this.name.toLowerCase()) {
 
+  /**
+   * @override
+   */
   needsToReadFileContents() {
@@ -46,2 +56,13 @@ if ("read" in this.entry) {
     }
+
+    // Handle aliases to `11ty.js` templates, avoid reading files in the alias, see #2279
+    // Here, we are short circuiting fallback to defaultRenderer, does not account for compile
+    // functions that call defaultRenderer explicitly
+    if (
+      this._defaultEngine &&
+      "needsToReadFileContents" in this._defaultEngine
+    ) {
+      return this._defaultEngine.needsToReadFileContents();
+    }
+
     return true;
@@ -74,6 +95,18 @@ }
   async getExtraDataFromFile(inputPath) {
-    if (!("getData" in this.entry) || this.entry.getData === false) {
+    if (this.entry.getData === false) {
       return;
     }
 
+    if (!("getData" in this.entry)) {
+      // Handle aliases to `11ty.js` templates, use upstream default engine data fetch, see #2279
+      if (
+        this._defaultEngine &&
+        "getExtraDataFromFile" in this._defaultEngine
+      ) {
+        return this._defaultEngine.getExtraDataFromFile(inputPath);
+      }
+
+      return;
+    }
+
     await this._runningInit();
@@ -148,3 +181,2 @@
     await this._runningInit();
-
     let defaultRenderer;
@@ -170,2 +202,5 @@ if (this._defaultEngine) {
       config: this.config,
+      addDependencies: (from, toArray = []) => {
+        this.config.uses.addDependency(from, toArray);
+      },
       defaultRenderer, // bind defaultRenderer to compile function
@@ -179,3 +214,8 @@ })(str, inputPath);
         // Promise, wait to bind
-        return fn.then((fn) => fn.bind({ defaultRenderer }));
+        return fn.then((fn) => {
+          if (typeof fn === "function") {
+            return fn.bind({ defaultRenderer });
+          }
+          return fn;
+        });
       } else if ("bind" in fn && typeof fn.bind === "function") {
@@ -193,3 +233,22 @@ return fn.bind({ defaultRenderer });
 
+  hasDependencies(inputPath) {
+    if (this.config.uses.getDependencies(inputPath) === false) {
+      return false;
+    }
+    return true;
+  }
+
+  isFileRelevantTo(inputPath, comparisonFile, includeLayouts) {
+    return this.config.uses.isFileRelevantTo(
+      inputPath,
+      comparisonFile,
+      includeLayouts
+    );
+  }
+
   getCompileCacheKey(str, inputPath) {
+    // Return this separately so we know whether or not to use the cached version
+    // but still return a key to cache this new render for next time
+    let useCache = !this.isFileRelevantTo(inputPath, lastModifiedFile, false);
+
     if (
@@ -205,5 +264,13 @@ this.entry.compileOptions &&
 
-      return this.entry.compileOptions.getCacheKey(str, inputPath);
+      return {
+        useCache,
+        key: this.entry.compileOptions.getCacheKey(str, inputPath),
+      };
     }
-    return super.getCompileCacheKey(str, inputPath);
+
+    let { key } = super.getCompileCacheKey(str, inputPath);
+    return {
+      useCache,
+      key,
+    };
   }
@@ -210,0 +277,0 @@

src/Engines/Handlebars.js

@@ -15,7 +15,2 @@ const HandlebarsLib = require("handlebars");
 
-    let partials = super.getPartials();
-    for (let name in partials) {
-      this.handlebarsLib.registerPartial(name, partials[name]);
-    }
-
     // TODO these all go to the same place (addHelper), add warnings for overwrites
@@ -33,2 +28,3 @@ this.addHelpers(this.config.handlebarsHelpers);
     for (let name in helpers) {
+      // We don’t need to wrap helpers for `page` or `eleventy`, this is provided for free by Handlebars
       this.addHelper(name, helpers[name]);
@@ -59,3 +55,15 @@ }
 
+  /**
+   * @override
+   */
+  async cachePartialFiles() {
+    let partials = await super.cachePartialFiles();
+    this.handlebarsLib.registerPartial(partials);
+    return partials;
+  }
+
   async compile(str) {
+    // Ensure partials are cached and registered.
+    await this.getPartials();
+
     let fn = this.handlebarsLib.compile(str);
@@ -62,0 +70,0 @@ return function (data) {

src/Engines/JavaScript.js

@@ -5,4 +5,4 @@ const { TemplatePath } = require("@11ty/eleventy-utils");
 const EleventyBaseError = require("../EleventyBaseError");
-const deleteRequireCache = require("../Util/DeleteRequireCache");
 const getJavaScriptData = require("../Util/GetJavaScriptData");
+const eventBus = require("../EventBus");
 
@@ -17,2 +17,11 @@ class JavaScriptTemplateNotDefined extends EleventyBaseError {}
     this.cacheable = false;
+
+    eventBus.on("eleventy.resourceModified", (inputPath) => {
+      inputPath = TemplatePath.addLeadingDotSlash(inputPath);
+
+      // Remove from cached instances when modified
+      if (inputPath in this.instances) {
+        delete this.instances[inputPath];
+      }
+    });
   }
@@ -39,6 +48,3 @@
     } else if (typeof mod === "function") {
-      if (
-        mod.prototype &&
-        ("data" in mod.prototype || "render" in mod.prototype)
-      ) {
+      if (mod.prototype && ("data" in mod.prototype || "render" in mod.prototype)) {
         if (!("render" in mod.prototype)) {
@@ -64,3 +70,3 @@ mod.prototype.render = noop;
 
-    const mod = this._getRequire(inputPath);
+    const mod = require(TemplatePath.absolutePath(inputPath));
     let inst = this._getInstance(mod);
@@ -78,7 +84,7 @@
 
-  _getRequire(inputPath) {
-    let requirePath = TemplatePath.absolutePath(inputPath);
-    return require(requirePath);
-  }
-
+  /**
+   * JavaScript files defer to the module loader rather than read the files to strings
+   *
+   * @override
+   */
   needsToReadFileContents() {
@@ -88,14 +94,2 @@ return false;
 
-  // only remove from cache once on startup (if it already exists)
-  initRequireCache(inputPath) {
-    let requirePath = TemplatePath.absolutePath(inputPath);
-    if (requirePath) {
-      deleteRequireCache(requirePath);
-    }
-
-    if (inputPath in this.instances) {
-      delete this.instances[inputPath];
-    }
-  }
-
   async getExtraDataFromFile(inputPath) {
@@ -115,4 +109,4 @@ let inst = this.getInstanceFromInputPath(inputPath);
       } else {
-        // note: bind creates a new function
-        fns[key] = configFns[key].bind(inst);
+        // note: wrapping creates a new function
+        fns[key] = JavaScript.wrapJavaScriptFunction(inst, configFns[key]);
       }
@@ -123,2 +117,15 @@ }
 
+  static wrapJavaScriptFunction(inst, fn) {
+    return function (...args) {
+      if (inst && inst.page) {
+        this.page = inst.page;
+      }
+      if (inst && inst.eleventy) {
+        this.eleventy = inst.eleventy;
+      }
+
+      return fn.call(this, ...args);
+    };
+  }
+
   async compile(str, inputPath) {
@@ -133,4 +140,8 @@ let inst;
     }
+
     if (inst && "render" in inst) {
       return function (data) {
+        // TODO does this do anything meaningful for non-classes?
+        // `inst` should have a normalized `render` function from _getInstance
+
         // only blow away existing inst.page if it has a page.url
@@ -137,0 +148,0 @@ if (!inst.page || inst.page.url) {

src/Engines/Liquid.js

@@ -56,2 +56,24 @@ const moo = require("moo");
 
+  static wrapFilter(fn) {
+    return function (...args) {
+      if (this.context && "get" in this.context) {
+        this.page = this.context.get(["page"]);
+        this.eleventy = this.context.get(["eleventy"]);
+      }
+
+      return fn.call(this, ...args);
+    };
+  }
+
+  // Shortcodes
+  static normalizeScope(context) {
+    let obj = {};
+    if (context) {
+      obj.ctx = context;
+      obj.page = context.get(["page"]);
+      obj.eleventy = context.get(["eleventy"]);
+    }
+    return obj;
+  }
+
   addCustomTags(tags) {
@@ -70,3 +92,3 @@ for (let name in tags) {
   addFilter(name, filter) {
-    this.liquidLib.registerFilter(name, filter);
+    this.liquidLib.registerFilter(name, Liquid.wrapFilter(filter));
   }
@@ -98,3 +120,3 @@
 
-  static async parseArguments(lexer, str, scope, engine) {
+  static parseArguments(lexer, str) {
     let argArray = [];
@@ -107,5 +129,4 @@
     if (typeof str === "string") {
-      // TODO key=value key2=value
-      // TODO JSON?
       lexer.reset(str);
+
       let arg = lexer.next();
@@ -126,3 +147,4 @@ while (arg) {
           // Otherwise they run out of order and can lead to undefined values for arguments in layout template shortcodes.
-          argArray.push(engine.evalValue(arg.value, scope));
+          // console.log( arg.value, scope, engine );
+          argArray.push(arg.value);
         }
@@ -133,35 +155,27 @@ arg = lexer.next();
 
-    return await Promise.all(argArray);
+    return argArray;
   }
 
-  static _normalizeShortcodeScope(ctx) {
-    let obj = {};
-    if (ctx) {
-      obj.page = ctx.get(["page"]);
-    }
-    return obj;
-  }
-
   addShortcode(shortcodeName, shortcodeFn) {
     let _t = this;
-    this.addTag(shortcodeName, function () {
+    this.addTag(shortcodeName, function (liquidEngine) {
       return {
-        parse: function (tagToken) {
+        parse(tagToken) {
           this.name = tagToken.name;
           this.args = tagToken.args;
         },
-        render: async function (scope) {
-          let argArray = await Liquid.parseArguments(
-            _t.argLexer,
-            this.args,
-            scope,
-            this.liquid
-          );
+        render: function* (ctx) {
+          let rawArgs = Liquid.parseArguments(_t.argLexer, this.args);
+          let argArray = [];
+          let contextScope = ctx.getAll();
+          for (let arg of rawArgs) {
+            let b = yield liquidEngine.evalValue(arg, contextScope);
+            argArray.push(b);
+          }
 
-          return Promise.resolve(
-            shortcodeFn.call(
-              Liquid._normalizeShortcodeScope(scope),
-              ...argArray
-            )
+          let ret = yield shortcodeFn.call(
+            Liquid.normalizeScope(ctx),
+            ...argArray
           );
+          return ret;
         },
@@ -176,3 +190,3 @@ };
       return {
-        parse: function (tagToken, remainTokens) {
+        parse(tagToken, remainTokens) {
           this.name = tagToken.name;
@@ -192,18 +206,23 @@ this.args = tagToken.args;
         },
-        render: function* (ctx) {
-          let argArray = yield Liquid.parseArguments(
-            _t.argLexer,
-            this.args,
-            ctx,
-            this.liquid
-          );
-          const html = yield this.liquid.renderer.renderTemplates(
+        render: function* (ctx, emitter) {
+          let rawArgs = Liquid.parseArguments(_t.argLexer, this.args);
+          let argArray = [];
+          let contextScope = ctx.getAll();
+          for (let arg of rawArgs) {
+            let b = yield liquidEngine.evalValue(arg, contextScope);
+            argArray.push(b);
+          }
+
+          const html = yield liquidEngine.renderer.renderTemplates(
             this.templates,
             ctx
           );
-          return shortcodeFn.call(
-            Liquid._normalizeShortcodeScope(ctx),
+
+          let ret = yield shortcodeFn.call(
+            Liquid.normalizeScope(ctx),
             html,
             ...argArray
           );
+          // emitter.write(ret);
+          return ret;
         },
@@ -226,4 +245,7 @@ };
 
+  // Don’t return a boolean if permalink is a function (see TemplateContent->renderPermalink)
   permalinkNeedsCompilation(str) {
-    return this.needsCompilation(str);
+    if (typeof str === "string") {
+      return this.needsCompilation(str);
+    }
   }
@@ -230,0 +252,0 @@

src/Engines/Markdown.js

@@ -21,3 +21,3 @@ const markdownIt = require("markdown-it");
     // This is separate so devs can pass in a new mdLib and still use the official eleventy plugin for markdown highlighting
-    if (this.config.markdownHighlighter) {
+    if (this.config.markdownHighlighter && typeof this.mdLib.set === "function") {
       this.mdLib.set({
@@ -28,2 +28,7 @@ highlight: this.config.markdownHighlighter,
 
+    if (typeof this.mdLib.disable === "function") {
+      // Disable indented code blocks by default (Issue #2438)
+      this.mdLib.disable("code");
+    }
+
     this.setEngineLib(this.mdLib);
@@ -30,0 +35,0 @@ }

src/Engines/Mustache.js

@@ -17,3 +17,3 @@ const MustacheLib = require("mustache");
   async compile(str) {
-    let partials = super.getPartials();
+    let partials = await super.getPartials();
 
@@ -20,0 +20,0 @@ return function (data) {

src/Engines/Nunjucks.js

@@ -6,122 +6,5 @@ const NunjucksLib = require("nunjucks");
 const EleventyErrorUtil = require("../EleventyErrorUtil");
-const EleventyBaseError = require("../EleventyBaseError");
+const EleventyShortcodeError = require("../EleventyShortcodeError");
 const eventBus = require("../EventBus");
 
-/*
- * The IFFE below apply a monkey-patch to Nunjucks internals to cache
- * compiled templates and re-use them where possible.
- */
-(function () {
-  if (!process.env.ELEVENTY_NUNJUCKS_SPEEDBOOST_OPTIN) {
-    return;
-  }
-
-  let templateCache = new Map();
-
-  let getKey = (obj) => {
-    return [
-      obj.path || obj.tmplStr,
-      obj.tmplStr.length,
-      obj.env.asyncFilters.length,
-      obj.env.extensionsList
-        .map((e) => {
-          return e.__id || "";
-        })
-        .join(":"),
-    ].join(" :: ");
-  };
-
-  let evictByPath = (path) => {
-    let keys = templateCache.keys();
-    // Likely to be slow; do we care?
-    for (let k of keys) {
-      if (k.indexOf(path) >= 0) {
-        templateCache.delete(k);
-      }
-    }
-  };
-  eventBus.on("eleventy.resourceModified", evictByPath);
-
-  let _compile = NunjucksLib.Template.prototype._compile;
-  NunjucksLib.Template.prototype._compile = function _wrap_compile(...args) {
-    if (!this.compiled && !this.tmplProps && templateCache.has(getKey(this))) {
-      let pathProps = templateCache.get(getKey(this));
-      this.blocks = pathProps.blocks;
-      this.rootRenderFunc = pathProps.rootRenderFunc;
-      this.compiled = true;
-    } else {
-      _compile.call(this, ...args);
-      templateCache.set(getKey(this), {
-        blocks: this.blocks,
-        rootRenderFunc: this.rootRenderFunc,
-      });
-    }
-  };
-
-  let extensionIdCounter = 0;
-  let addExtension = NunjucksLib.Environment.prototype.addExtension;
-  NunjucksLib.Environment.prototype.addExtension = function _wrap_addExtension(
-    name,
-    ext
-  ) {
-    if (!("__id" in ext)) {
-      ext.__id = extensionIdCounter++;
-    }
-    return addExtension.call(this, name, ext);
-  };
-
-  // NunjucksLib.runtime.Frame.prototype.set is the hotest in-template method.
-  // We replace it with a version that doesn't allocate a `parts` array on
-  // repeat key use.
-  let partsCache = new Map();
-  let partsFromCache = (name) => {
-    if (partsCache.has(name)) {
-      return partsCache.get(name);
-    }
-
-    let parts = name.split(".");
-    partsCache.set(name, parts);
-    return parts;
-  };
-
-  let frameSet = NunjucksLib.runtime.Frame.prototype.set;
-  NunjucksLib.runtime.Frame.prototype.set = function _replacement_set(
-    name,
-    val,
-    resolveUp
-  ) {
-    let parts = partsFromCache(name);
-    let frame = this;
-    let obj = frame.variables;
-
-    if (resolveUp) {
-      if ((frame = this.resolve(parts[0], true))) {
-        frame.set(name, val);
-        return;
-      }
-    }
-
-    // A slightly faster version of the intermediate object allocation loop
-    let count = parts.length - 1;
-    let i = 0;
-    let id = parts[0];
-    while (i < count) {
-      // TODO(zachleat) use Object.hasOwn when supported
-      if ("hasOwnProperty" in obj) {
-        if (!obj.hasOwnProperty(id)) {
-          obj = obj[id] = {};
-        }
-      } else if (!(id in obj)) {
-        // Handle Objects with null prototypes (Nunjucks looping stuff)
-        obj = obj[id] = {};
-      }
-
-      id = parts[++i];
-    }
-    obj[id] = val;
-  };
-})();
-
-class EleventyShortcodeError extends EleventyBaseError {}
-
 class Nunjucks extends TemplateEngine {
@@ -133,2 +16,7 @@ constructor(name, dirs, config) {
 
+    this.nunjucksPrecompiledTemplates =
+      this.config.nunjucksPrecompiledTemplates || {};
+    this._usingPrecompiled =
+      Object.keys(this.nunjucksPrecompiledTemplates).length > 0;
+
     this.setLibrary(this.config.libraryOverrides.njk);
@@ -139,12 +27,46 @@
 
+  _setEnv(override) {
+    if (override) {
+      this.njkEnv = override;
+    } else if (this._usingPrecompiled) {
+      // Precompiled templates to avoid eval!
+      function NodePrecompiledLoader() {}
+      NodePrecompiledLoader.prototype.getSource = (name) => {
+        // https://github.com/mozilla/nunjucks/blob/fd500902d7c88672470c87170796de52fc0f791a/nunjucks/src/precompiled-loader.js#L5
+        return {
+          src: {
+            type: "code",
+            obj: this.nunjucksPrecompiledTemplates[name],
+          },
+          // Maybe add this?
+          // path,
+          // noCache: true
+        };
+      };
+
+      this.njkEnv = new NunjucksLib.Environment(
+        new NodePrecompiledLoader(),
+        this.nunjucksEnvironmentOptions
+      );
+    } else {
+      let fsLoader = new NunjucksLib.FileSystemLoader([
+        super.getIncludesDir(),
+        TemplatePath.getWorkingDir(),
+      ]);
+
+      this.njkEnv = new NunjucksLib.Environment(
+        fsLoader,
+        this.nunjucksEnvironmentOptions
+      );
+    }
+
+    this.config.events.emit("eleventy.engine.njk", {
+      nunjucks: NunjucksLib,
+      environment: this.njkEnv,
+    });
+  }
+
   setLibrary(override) {
-    let fsLoader = new NunjucksLib.FileSystemLoader([
-      super.getIncludesDir(),
-      TemplatePath.getWorkingDir(),
-    ]);
+    this._setEnv(override);
 
-    this.njkEnv =
-      override ||
-      new NunjucksLib.Environment(fsLoader, this.nunjucksEnvironmentOptions);
-
     // Correct, but overbroad. Better would be to evict more granularly, but
@@ -179,8 +101,38 @@ // resolution from paths isn't straightforward.
 
-  addFilters(helpers, isAsync) {
-    for (let name in helpers) {
-      this.njkEnv.addFilter(name, helpers[name], isAsync);
+  addFilters(filters, isAsync) {
+    for (let name in filters) {
+      this.njkEnv.addFilter(name, Nunjucks.wrapFilter(filters[name]), isAsync);
     }
   }
 
+  static wrapFilter(fn) {
+    return function (...args) {
+      if (this.ctx && this.ctx.page) {
+        this.page = this.ctx.page;
+      }
+      if (this.ctx && this.ctx.eleventy) {
+        this.eleventy = this.ctx.eleventy;
+      }
+
+      return fn.call(this, ...args);
+    };
+  }
+
+  // Shortcodes
+  static normalizeContext(context) {
+    let obj = {};
+    if (context.ctx) {
+      obj.ctx = context.ctx;
+
+      if (context.ctx.page) {
+        obj.page = context.ctx.page;
+      }
+
+      if (context.ctx.eleventy) {
+        obj.eleventy = context.ctx.eleventy;
+      }
+    }
+    return obj;
+  }
+
   addCustomTags(tags) {
@@ -227,11 +179,2 @@ for (let name in tags) {
 
-  static _normalizeShortcodeContext(context) {
-    let obj = {};
-    if (context.ctx && context.ctx.page) {
-      obj.ctx = context.ctx;
-      obj.page = context.ctx.page;
-    }
-    return obj;
-  }
-
   _getShortcodeFn(shortcodeName, shortcodeFn, isAsync = false) {
@@ -271,5 +214,8 @@ return function ShortcodeFunction() {
           shortcodeFn
-            .call(Nunjucks._normalizeShortcodeContext(context), ...argArray)
+            .call(Nunjucks.normalizeContext(context), ...argArray)
             .then(function (returnValue) {
-              resolve(null, new NunjucksLib.runtime.SafeString(returnValue));
+              resolve(
+                null,
+                new NunjucksLib.runtime.SafeString("" + returnValue)
+              );
             })
@@ -288,8 +234,7 @@ .catch(function (e) {
           try {
-            return new NunjucksLib.runtime.SafeString(
-              shortcodeFn.call(
-                Nunjucks._normalizeShortcodeContext(context),
-                ...argArray
-              )
+            let ret = shortcodeFn.call(
+              Nunjucks.normalizeContext(context),
+              ...argArray
             );
+            return new NunjucksLib.runtime.SafeString("" + ret);
           } catch (e) {
@@ -342,3 +287,3 @@ throw new EleventyShortcodeError(
               .call(
-                Nunjucks._normalizeShortcodeContext(context),
+                Nunjucks.normalizeContext(context),
                 bodyContent,
@@ -366,3 +311,3 @@ ...argArray
                   shortcodeFn.call(
-                    Nunjucks._normalizeShortcodeContext(context),
+                    Nunjucks.normalizeContext(context),
                     bodyContent,
@@ -398,4 +343,7 @@ ...argArray
 
+  // Don’t return a boolean if permalink is a function (see TemplateContent->renderPermalink)
   permalinkNeedsCompilation(str) {
-    return this.needsCompilation(str);
+    if (typeof str === "string") {
+      return this.needsCompilation(str);
+    }
   }
@@ -410,2 +358,3 @@
     let commentStart = optsTags.variableStart || "{#";
+
     return (
@@ -479,12 +428,12 @@ str.indexOf(blockStart) !== -1 ||
 
-    return Array.from(new Set(symbols));
+    let uniqueSymbols = Array.from(new Set(symbols));
+    return uniqueSymbols;
   }
 
   async compile(str, inputPath) {
-    // for(let loader of this.njkEnv.loaders) {
-    //   loader.cache = {};
-    // }
+    let tmpl;
 
-    let tmpl;
-    if (!inputPath || inputPath === "njk" || inputPath === "md") {
+    if (this._usingPrecompiled) {
+      tmpl = this.njkEnv.getTemplate(str, true);
+    } else if (!inputPath || inputPath === "njk" || inputPath === "md") {
       tmpl = new NunjucksLib.Template(str, this.njkEnv, null, true);
@@ -491,0 +440,0 @@ } else {

src/Engines/TemplateEngine.js

@@ -1,2 +0,1 @@
-const fastglob = require("fast-glob");
 const fs = require("fs");
@@ -83,5 +82,3 @@ const { TemplatePath } = require("@11ty/eleventy-utils");
     if (!this._extensionEntries) {
-      this._extensionEntries = this.extensionMap.getExtensionEntriesFromKey(
-        this.name
-      );
+      this._extensionEntries = this.extensionMap.getExtensionEntriesFromKey(this.name);
     }
@@ -99,6 +96,5 @@ return this._extensionEntries;
 
-  // TODO make async
-  getPartials() {
+  async getPartials() {
     if (!this.partialsHaveBeenCached) {
-      this.partials = this.cachePartialFiles();
+      this.partials = await this.cachePartialFiles();
     }
@@ -109,41 +105,63 @@
 
-  // TODO make async
-  cachePartialFiles() {
-    // This only runs if getPartials() is called, which is only for Mustache/Handlebars
+  /**
+   * Search for and cache partial files.
+   *
+   * This only runs if getPartials() is called, which only runs if you compile a Mustache/Handlebars template.
+   *
+   * @protected
+   */
+  async cachePartialFiles() {
     this.partialsHaveBeenCached = true;
-    let partials = {};
-    let prefix = this.includesDir + "/**/*.";
-    // TODO: reuse mustache partials in handlebars?
-    let partialFiles = [];
+
+    let results = [];
     if (this.includesDir) {
-      let bench = this.benchmarks.aggregate.get("Searching the file system");
+      // TODO move this to use FileSystemSearch instead.
+      const fastglob = require("fast-glob");
+
+      let bench = this.benchmarks.aggregate.get("Searching the file system (partials)");
       bench.before();
-      this.extensions.forEach(function (extension) {
-        partialFiles = partialFiles.concat(
-          fastglob.sync(prefix + extension, {
-            caseSensitiveMatch: false,
-            dot: true,
-          })
-        );
-      });
+
+      let prefix = this.includesDir + "/**/*.";
+      let partialFiles = [];
+      await Promise.all(
+        this.extensions.map(async function (extension) {
+          partialFiles = partialFiles.concat(
+            await fastglob(prefix + extension, {
+              caseSensitiveMatch: false,
+              dot: true,
+            })
+          );
+        })
+      );
+
       bench.after();
-    }
 
-    partialFiles = TemplatePath.addLeadingDotSlashArray(partialFiles);
+      results = await Promise.all(
+        partialFiles.map((partialFile) => {
+          partialFile = TemplatePath.addLeadingDotSlash(partialFile);
+          let partialPath = TemplatePath.stripLeadingSubPath(partialFile, this.includesDir);
+          let partialPathNoExt = partialPath;
+          this.extensions.forEach(function (extension) {
+            partialPathNoExt = TemplatePath.removeExtension(partialPathNoExt, "." + extension);
+          });
 
-    for (let j = 0, k = partialFiles.length; j < k; j++) {
-      let partialPath = TemplatePath.stripLeadingSubPath(
-        partialFiles[j],
-        this.includesDir
+          return fs.promises
+            .readFile(partialFile, {
+              encoding: "utf8",
+            })
+            .then((content) => {
+              return {
+                content,
+                path: partialPathNoExt,
+              };
+            });
+        })
       );
-      let partialPathNoExt = partialPath;
-      this.extensions.forEach(function (extension) {
-        partialPathNoExt = TemplatePath.removeExtension(
-          partialPathNoExt,
-          "." + extension
-        );
-      });
-      partials[partialPathNoExt] = fs.readFileSync(partialFiles[j], "utf8");
     }
 
+    let partials = {};
+    for (let result of results) {
+      partials[result.path] = result.content;
+    }
+
     debug(
@@ -157,4 +175,13 @@ `${this.includesDir}/*.{${this.extensions}} found partials for: %o`,
 
+  /**
+   * @protected
+   */
   setEngineLib(engineLib) {
     this.engineLib = engineLib;
+
+    // Run engine amendments (via issue #2438)
+    for (let amendment of this.config.libraryAmendments[this.name] || []) {
+      // TODO it’d be nice if this were async friendly
+      amendment(engineLib);
+    }
   }
@@ -185,8 +212,12 @@
 
-  initRequireCache() {
-    // do nothing
-  }
+  getCompileCacheKey(str, inputPath) {
+    // Changing to use inputPath and contents, using only file contents (`str`) caused issues when two
+    // different files had identical content (2.0.0-canary.16)
 
-  getCompileCacheKey(str, inputPath) {
-    return str;
+    // Caches are now segmented based on inputPath so using inputPath here is superfluous (2.0.0-canary.19)
+    // But we do want a non-falsy value here even if `str` is an empty string.
+    return {
+      useCache: true,
+      key: inputPath + str,
+    };
   }
@@ -207,2 +238,11 @@
 
+  /**
+   * Make sure compile is implemented downstream.
+   * @abstract
+   * @return {Promise}
+   */
+  async compile() {
+    throw new Error("compile() must be implemented by engine");
+  }
+
   // See https://www.11ty.dev/docs/watch-serve/#watch-javascript-dependencies
@@ -212,4 +252,15 @@ static shouldSpiderJavaScriptDependencies() {
   }
+
+  hasDependencies(inputPath) {
+    if (this.config.uses.getDependencies(inputPath) === false) {
+      return false;
+    }
+    return true;
+  }
+
+  isFileRelevantTo(inputPath, comparisonFile) {
+    return this.config.uses.isFileRelevantTo(inputPath, comparisonFile);
+  }
 }
 
 module.exports = TemplateEngine;

src/Filters/GetCollectionItem.js

@@ -7,3 +7,3 @@ module.exports = function getCollectionItem(collection, page, modifier = 0) {
       item.inputPath === page.inputPath &&
-      item.outputPath === page.outputPath
+      (item.outputPath === page.outputPath || item.url === page.url)
     ) {
@@ -10,0 +10,0 @@ index = j;

src/Filters/ServerlessUrl.js

 const { compile } = require("path-to-regexp");
+const normalizeServerlessUrl = require("../Util/NormalizeServerlessUrl");
 
 function stringify(url, urlData = {}) {
-  let fn = compile(url, { encode: encodeURIComponent });
+  url = normalizeServerlessUrl(url);
+
+  let fn = compile(url, {
+    encode: encodeURIComponent,
+  });
   return fn(urlData);
@@ -6,0 +11,0 @@ }

src/Filters/Slugify.js

@@ -8,2 +8,3 @@ const slugify = require("@sindresorhus/slugify");
       {
+        // lowercase: true, // default
         decamelize: false,
@@ -10,0 +11,0 @@ },

src/Filters/Url.js

@@ -13,3 +13,3 @@ const { TemplatePath } = require("@11ty/eleventy-utils");
 
-// This is also used in the Eleventy Navigation plugin
+// Note: This filter is used in the Eleventy Navigation plugin in versions prior to 0.3.4
 module.exports = function (url, pathPrefix) {
@@ -19,3 +19,3 @@ // work with undefined
 
-  if (isValidUrl(url) || (url.indexOf("//") === 0 && url !== "//")) {
+  if (isValidUrl(url) || (url.startsWith("//") && url !== "//")) {
     return url;
@@ -26,3 +26,3 @@ }
     // When you retrieve this with config.getFilter("url") it
-    // grabs the pathPrefix argument from your config for you.
+    // grabs the pathPrefix argument from your config for you (see defaultConfig.js)
     throw new Error("pathPrefix (String) is required in the `url` filter.");
@@ -29,0 +29,0 @@ }

src/Plugins/DefaultServerlessFunctionContent.js

@@ -10,3 +10,3 @@ const { EleventyServerless } = require("@11ty/eleventy");
     path: new URL(event.rawUrl).pathname,
-    query: event.queryStringParameters,
+    query: event.multiValueQueryStringParameters || event.queryStringParameters,
     functionsDir: "%%FUNCTIONS_DIR%%",
@@ -13,0 +13,0 @@ });

src/Plugins/Pagination.js

@@ -1,5 +0,9 @@
-const lodashChunk = require("lodash/chunk");
-const lodashGet = require("lodash/get");
-const lodashSet = require("lodash/set");
+const lodashChunk = require("lodash.chunk");
+const lodashGet = require("lodash.get");
+const lodashSet = require("lodash.set");
+const { isPlainObject } = require("@11ty/eleventy-utils");
+
 const EleventyBaseError = require("../EleventyBaseError");
+const { DeepCopy } = require("../Util/Merge");
+const { ProxyWrap } = require("../Util/ProxyWrap");
 
@@ -10,3 +14,3 @@ class PaginationConfigError extends EleventyBaseError {}
 class Pagination {
-  constructor(data, config) {
+  constructor(tmpl, data, config) {
     if (!config) {
@@ -20,5 +24,13 @@ throw new PaginationConfigError(
 
+    this.setTemplate(tmpl);
     this.setData(data);
   }
 
+  get inputPathForErrorMessages() {
+    if (this.template) {
+      return ` (${this.template.inputPath})`;
+    }
+    return "";
+  }
+
   static hasPagination(data) {
@@ -30,3 +42,5 @@ return "pagination" in data;
     if (!this.data) {
-      throw new Error("Missing `setData` call for Pagination object.");
+      throw new Error(
+        `Missing \`setData\` call for Pagination object${this.inputPathForErrorMessages}`
+      );
     }
@@ -46,5 +60,3 @@ return Pagination.hasPagination(this.data);
         throw new PaginationError(
-          `Pagination circular reference${
-            this.template ? ` on ${this.template.inputPath}` : ""
-          }, data:\`${key}\` iterates over both the \`${tag}\` tag and also supplies pages to that tag.`
+          `Pagination circular reference${this.inputPathForErrorMessages}, data:\`${key}\` iterates over both the \`${tag}\` tag and also supplies pages to that tag.`
         );
@@ -65,6 +77,8 @@ }
       throw new Error(
-        "Misconfigured pagination data in template front matter (YAML front matter precaution: did you use tabs and not spaces for indentation?)."
+        `Misconfigured pagination data in template front matter${this.inputPathForErrorMessages} (YAML front matter precaution: did you use tabs and not spaces for indentation?).`
       );
     } else if (!("size" in data.pagination)) {
-      throw new Error("Missing pagination size in front matter data.");
+      throw new Error(
+        `Missing pagination size in front matter data${this.inputPathForErrorMessages}`
+      );
     }
@@ -125,3 +139,3 @@ this.circularReferenceCheck(data);
 
-  resolveDataToObjectValues() {
+  shouldResolveDataToObjectValues() {
     if ("resolve" in this.data.pagination) {
@@ -157,3 +171,3 @@ return this.data.pagination.resolve === "values";
       throw new Error(
-        `Could not find pagination data, went looking for: ${key}`
+        `Could not find pagination data${this.inputPathForErrorMessages}, went looking for: ${key}`
       );
@@ -168,6 +182,12 @@ }
       keys = this.fullDataSet;
-    } else if (this.resolveDataToObjectValues()) {
-      keys = Object.values(this.fullDataSet);
+    } else if (isPlainObject(this.fullDataSet)) {
+      if (this.shouldResolveDataToObjectValues()) {
+        keys = Object.values(this.fullDataSet);
+      } else {
+        keys = Object.keys(this.fullDataSet);
+      }
     } else {
-      keys = Object.keys(this.fullDataSet);
+      throw new Error(
+        `Unexpected data found in pagination target${this.inputPathForErrorMessages}: expected an Array or an Object.`
+      );
     }
@@ -183,3 +203,7 @@
       // we don’t need to make a copy of this because we .slice() above to create a new copy
-      result = this.data.pagination.before(result, this.data);
+      let fns = {};
+      if (this.config) {
+        fns = this.config.javascriptFunctions;
+      }
+      result = this.data.pagination.before.call(fns, result, this.data);
     }
@@ -200,12 +224,14 @@
     if (!this.data) {
-      throw new Error("Missing `setData` call for Pagination object.");
+      throw new Error(
+        `Missing \`setData\` call for Pagination object${this.inputPathForErrorMessages}`
+      );
     }
 
-    return lodashChunk(this.target, this.size);
-  }
+    const chunks = lodashChunk(this.target, this.size);
 
-  // TODO this name is not good
-  // “To cancel” means to not write the original root template
-  cancel() {
-    return this.hasPagination();
+    if (this.data.pagination && this.data.pagination.generatePageOnEmptyData) {
+      return chunks.length ? chunks : [[]];
+    } else {
+      return chunks;
+    }
   }
@@ -225,23 +251,4 @@
 
-  getOverrideData(pageItems) {
-    let override = {
-      pagination: {
-        data: this.data.pagination.data,
-        size: this.data.pagination.size,
-        alias: this.alias,
-        items: pageItems,
-      },
-    };
-
-    if (this.alias) {
-      lodashSet(override, this.alias, this.getNormalizedItems(pageItems));
-    }
-
-    return override;
-  }
-
   getOverrideDataPages(items, pageNumber) {
-    let obj = {
-      pages: this.size === 1 ? items.map((entry) => entry[0]) : items,
-
+    return {
       // See Issue #345 for more examples
@@ -265,7 +272,5 @@ page: {
     };
-
-    return obj;
   }
 
-  getOverrideDataLinks(pageNumber, templates, links) {
+  getOverrideDataLinks(pageNumber, templateCount, links) {
     let obj = {};
@@ -278,3 +283,3 @@
     obj.nextPageLink =
-      pageNumber < templates.length - 1 ? links[pageNumber + 1] : null;
+      pageNumber < templateCount - 1 ? links[pageNumber + 1] : null;
     obj.next = obj.nextPageLink;
@@ -291,3 +296,3 @@
 
-  getOverrideDataHrefs(pageNumber, templates, hrefs) {
+  getOverrideDataHrefs(pageNumber, templateCount, hrefs) {
     let obj = {};
@@ -298,3 +303,3 @@
     obj.nextPageHref =
-      pageNumber < templates.length - 1 ? hrefs[pageNumber + 1] : null;
+      pageNumber < templateCount - 1 ? hrefs[pageNumber + 1] : null;
 
@@ -319,3 +324,5 @@ obj.firstPageHref = hrefs.length > 0 ? hrefs[0] : null;
     if (!this.data) {
-      throw new Error("Missing `setData` call for Pagination object.");
+      throw new Error(
+        `Missing \`setData\` call for Pagination object${this.inputPathForErrorMessages}`
+      );
     }
@@ -327,56 +334,108 @@
 
-    let pages = [];
+    let entries = [];
     let items = this.chunkedItems;
-    let tmpl = this.template;
-    let templates = [];
+    let pages = this.size === 1 ? items.map((entry) => entry[0]) : items;
+
     let links = [];
     let hrefs = [];
-    let overrides = [];
 
-    for (let pageNumber = 0, k = items.length; pageNumber < k; pageNumber++) {
-      let cloned = tmpl.clone();
+    let hasPermalinkField = Boolean(this.data[this.config.keys.permalink]);
+    let hasComputedPermalinkField = Boolean(
+      this.data.eleventyComputed &&
+        this.data.eleventyComputed[this.config.keys.permalink]
+    );
 
-      // TODO maybe also move this permalink additions up into the pagination class
-      let hasPermalinkField = Boolean(this.data[this.config.keys.permalink]);
-      let hasComputedPermalinkField = Boolean(
-        this.data.eleventyComputed &&
-          this.data.eleventyComputed[this.config.keys.permalink]
-      );
-      if (pageNumber > 0 && !(hasPermalinkField || hasComputedPermalinkField)) {
+    // Do *not* pass collections through DeepCopy, we’ll re-add them back in later.
+    let collections = this.data.collections;
+    if (collections) {
+      delete this.data.collections;
+    }
+
+    let parentData = DeepCopy(
+      {
+        pagination: {
+          data: this.data.pagination.data,
+          size: this.data.pagination.size,
+          alias: this.alias,
+          pages,
+        },
+      },
+      this.data
+    );
+
+    // Restore skipped collections
+    if (collections) {
+      this.data.collections = collections;
+      // Keep the original reference to the collections, no deep copy!!
+      parentData.collections = collections;
+    }
+
+    // TODO future improvement dea: use a light Template wrapper for paged template clones (PagedTemplate?)
+    // so that we don’t have the memory cost of the full template (and can reuse the parent
+    // template for some things)
+
+    for (let pageNumber = 0; pageNumber < items.length; pageNumber++) {
+      let cloned = this.template.clone();
+
+      if (pageNumber > 0 && !hasPermalinkField && !hasComputedPermalinkField) {
         cloned.setExtraOutputSubdirectory(pageNumber);
       }
 
-      templates.push(cloned);
-
-      let override = this.getOverrideData(items[pageNumber]);
+      let paginationData = {
+        pagination: {
+          items: items[pageNumber],
+        },
+        page: {},
+      };
       Object.assign(
-        override.pagination,
+        paginationData.pagination,
         this.getOverrideDataPages(items, pageNumber)
       );
 
-      overrides.push(override);
-      cloned.setPaginationData(override);
+      if (this.alias) {
+        lodashSet(
+          paginationData,
+          this.alias,
+          this.getNormalizedItems(items[pageNumber])
+        );
+      }
 
+      // Do *not* deep merge pagination data! See https://github.com/11ty/eleventy/issues/147#issuecomment-440802454
+      let clonedData = ProxyWrap(paginationData, parentData);
+
+      let { rawPath, path, href } = await cloned.getOutputLocations(clonedData);
       // TO DO subdirectory to links if the site doesn’t live at /
-      // TODO missing data argument means Template.getData is regenerated, maybe doesn’t matter because of data cache?
-      let { rawPath, href } = await cloned.getOutputLocations();
       links.push("/" + rawPath);
       hrefs.push(href);
+
+      // page.url and page.outputPath are used to avoid another getOutputLocations call later, see Template->addComputedData
+      clonedData.page.url = href;
+      clonedData.page.outputPath = path;
+
+      entries.push({
+        template: cloned,
+        data: clonedData,
+      });
     }
 
     // we loop twice to pass in the appropriate prev/next links (already full generated now)
-    for (let pageNumber = 0; pageNumber < templates.length; pageNumber++) {
-      let linksObj = this.getOverrideDataLinks(pageNumber, templates, links);
-      Object.assign(overrides[pageNumber].pagination, linksObj);
+    let numberOfEntries = entries.length;
+    for (let pageNumber = 0; pageNumber < numberOfEntries; pageNumber++) {
+      let linksObj = this.getOverrideDataLinks(
+        pageNumber,
+        numberOfEntries,
+        links
+      );
 
-      let hrefsObj = this.getOverrideDataHrefs(pageNumber, templates, hrefs);
-      Object.assign(overrides[pageNumber].pagination, hrefsObj);
+      Object.assign(entries[pageNumber].data.pagination, linksObj);
 
-      let cloned = templates[pageNumber];
-      cloned.setPaginationData(overrides[pageNumber]);
-
-      pages.push(cloned);
+      let hrefsObj = this.getOverrideDataHrefs(
+        pageNumber,
+        numberOfEntries,
+        hrefs
+      );
+      Object.assign(entries[pageNumber].data.pagination, hrefsObj);
     }
 
-    return pages;
+    return entries;
   }
@@ -383,0 +442,0 @@ }

src/Plugins/RenderPlugin.js

 const fs = require("fs");
 const fsp = fs.promises;
-const isPlainObject = require("../Util/IsPlainObject");
-const { TemplatePath } = require("@11ty/eleventy-utils");
+const { TemplatePath, isPlainObject } = require("@11ty/eleventy-utils");
 
 // TODO add a first-class Markdown component to expose this using Markdown-only syntax (will need to be synchronous for markdown-it)
 
+const Merge = require("../Util/Merge");
+const { ProxyWrap } = require("../Util/ProxyWrap");
+const TemplateDataInitialGlobalData = require("../TemplateDataInitialGlobalData");
+const EleventyShortcodeError = require("../EleventyShortcodeError");
 const TemplateRender = require("../TemplateRender");
 const TemplateConfig = require("../TemplateConfig");
+const EleventyErrorUtil = require("../EleventyErrorUtil");
 const Liquid = require("../Engines/Liquid");
 
-function normalizeDirectories(dir = {}) {
-  return Object.assign(
-    {
-      input: ".",
-    },
-    dir
-  );
-}
-
-async function render(
-  content,
-  templateLang = "html",
-  normalizedDirs = {},
-  { templateConfig, extensionMap }
-) {
+async function compile(content, templateLang, { templateConfig, extensionMap } = {}) {
   if (!templateConfig) {
-    templateConfig = new TemplateConfig();
+    templateConfig = new TemplateConfig(null, false);
   }
 
-  let tr = new TemplateRender(
-    templateLang,
-    normalizedDirs.input,
-    templateConfig
-  );
+  // Breaking change in 2.0+, previous default was `html` and now we default to the page template syntax
+  if (!templateLang) {
+    templateLang = this.page.templateSyntax;
+  }
+
+  let cfg = templateConfig;
+  // templateConfig might already be a userconfig
+  if (cfg instanceof TemplateConfig) {
+    cfg = cfg.getConfig();
+  }
+
+  let tr = new TemplateRender(templateLang, cfg.dir.input, templateConfig);
   tr.extensionMap = extensionMap;
@@ -50,20 +47,10 @@ tr.setEngineOverride(templateLang);
 // No templateLang default, it should infer from the inputPath.
-async function renderFile(
-  inputPath,
-  templateLang,
-  normalizedDirs = {},
-  { templateConfig, extensionMap }
-) {
+async function compileFile(inputPath, { templateConfig, extensionMap, config } = {}, templateLang) {
   if (!inputPath) {
-    throw new Error(
-      "Missing file path argument passed to the `renderFile` shortcode."
-    );
+    throw new Error("Missing file path argument passed to the `renderFile` shortcode.");
   }
 
-  if (
-    !fs.existsSync(TemplatePath.normalizeOperatingSystemFilePath(inputPath))
-  ) {
+  if (!fs.existsSync(TemplatePath.normalizeOperatingSystemFilePath(inputPath))) {
     throw new Error(
-      "Could not find render plugin file for the `renderFile` shortcode, looking for: " +
-        inputPath
+      "Could not find render plugin file for the `renderFile` shortcode, looking for: " + inputPath
     );
@@ -73,6 +60,10 @@ }
   if (!templateConfig) {
-    templateConfig = new TemplateConfig();
+    templateConfig = new TemplateConfig(null, false);
   }
+  if (config && typeof config === "function") {
+    await config(templateConfig.userConfig);
+  }
 
-  let tr = new TemplateRender(inputPath, normalizedDirs.input, templateConfig);
+  let cfg = templateConfig.getConfig();
+  let tr = new TemplateRender(inputPath, cfg.dir.input, templateConfig);
   tr.extensionMap = extensionMap;
@@ -92,3 +83,40 @@ if (templateLang) {
 
+async function renderShortcodeFn(fn, data) {
+  if (fn === undefined) {
+    return;
+  } else if (typeof fn !== "function") {
+    throw new Error(`The \`compile\` function did not return a function. Received ${fn}`);
+  }
+
+  // if the user passes a string or other literal, remap to an object.
+  if (!isPlainObject(data)) {
+    data = {
+      _: data,
+    };
+  }
+
+  if ("data" in this && isPlainObject(this.data)) {
+    // when options.accessGlobalData is true, this allows the global data
+    // to be accessed inside of the shortcode as a fallback
+    data = ProxyWrap(data, this.data);
+  } else {
+    // save `page` and `eleventy` for reuse
+    data.page = this.page;
+    data.eleventy = this.eleventy;
+  }
+
+  return fn(data);
+}
+
 function EleventyPlugin(eleventyConfig, options = {}) {
+  let opts = Object.assign(
+    {
+      tagName: "renderTemplate",
+      tagNameFile: "renderFile",
+      templateConfig: null,
+      accessGlobalData: false,
+    },
+    options
+  );
+
   function liquidTemplateTag(liquidEngine, tagName) {
@@ -114,22 +142,33 @@ // via https://github.com/harttle/liquidjs/blob/b5a22fa0910c708fe7881ef170ed44d3594e18f3/src/builtin/tags/raw.ts
       },
-      render: async function (ctx) {
+      render: function* (ctx) {
         let normalizedContext = {};
         if (ctx) {
+          if (opts.accessGlobalData) {
+            // parent template data cascade
+            normalizedContext.data = ctx.getAll();
+          }
+
           normalizedContext.page = ctx.get(["page"]);
+          normalizedContext.eleventy = ctx.get(["eleventy"]);
         }
 
-        let argArray = await Liquid.parseArguments(
-          null,
-          this.args,
-          ctx,
-          this.liquid
-        );
+        let rawArgs = Liquid.parseArguments(null, this.args);
+        let argArray = [];
+        let contextScope = ctx.getAll();
+        for (let arg of rawArgs) {
+          let b = yield liquidEngine.evalValue(arg, contextScope);
+          argArray.push(b);
+        }
 
+        // plaintext paired shortcode content
         let body = this.tokens.map((token) => token.getText()).join("");
 
-        return renderStringShortcodeFn.call(
+        let ret = _renderStringShortcodeFn.call(
           normalizedContext,
           body,
+          // templateLang, data
           ...argArray
         );
+        yield ret;
+        return ret;
       },
@@ -163,6 +202,3 @@ };
         // or when we've found the matching "endraw" block
-        while (
-          (matches = parser.tokens._extractRegex(rawBlockRegex)) &&
-          rawLevel > 0
-        ) {
+        while ((matches = parser.tokens._extractRegex(rawBlockRegex)) && rawLevel > 0) {
           const all = matches[0];
@@ -204,3 +240,10 @@ const pre = matches[1];
           normalizedContext.ctx = context.ctx;
+
+          // TODO .data
+          // if(opts.accessGlobalData) {
+          //   normalizedContext.data = context.ctx;
+          // }
+
           normalizedContext.page = context.ctx.page;
+          normalizedContext.eleventy = context.ctx.eleventy;
         }
@@ -212,3 +255,3 @@
               new EleventyShortcodeError(
-                `Error with Nunjucks paired shortcode \`${shortcodeName}\`${EleventyErrorUtil.convertErrorToString(
+                `Error with Nunjucks paired shortcode \`${tagName}\`${EleventyErrorUtil.convertErrorToString(
                   e
@@ -221,5 +264,6 @@ )}`
           Promise.resolve(
-            renderStringShortcodeFn.call(
+            _renderStringShortcodeFn.call(
               normalizedContext,
               bodyContent,
+              // templateLang, data
               ...argArray
@@ -234,3 +278,3 @@ )
                 new EleventyShortcodeError(
-                  `Error with Nunjucks paired shortcode \`${shortcodeName}\`${EleventyErrorUtil.convertErrorToString(
+                  `Error with Nunjucks paired shortcode \`${tagName}\`${EleventyErrorUtil.convertErrorToString(
                     e
@@ -247,10 +291,2 @@ )}`
 
-  let opts = Object.assign(
-    {
-      tagName: "renderTemplate",
-      tagNameFile: "renderFile",
-    },
-    options
-  );
-
   // This will only work on 1.0.0-beta.5+ but is only necessary if you want to reuse your config inside of template shortcodes.
@@ -268,88 +304,111 @@ // Just rendering raw templates (without filters, shortcodes, etc. from your config) will work fine on old versions.
 
-  async function renderStringShortcodeFn(content, templateLang, data = {}) {
-    let fn = await render.call(
-      this,
-      content,
-      templateLang,
-      normalizeDirectories(eleventyConfig.dir),
-      {
-        templateConfig,
-        extensionMap,
-      }
-    );
-
-    if (fn === undefined) {
-      return;
-    } else if (typeof fn !== "function") {
-      throw new Error(
-        `The \`compile\` function did not return a function. Received ${fn}`
-      );
+  async function _renderStringShortcodeFn(content, templateLang, data = {}) {
+    // Default is fn(content, templateLang, data) but we want to support fn(content, data) too
+    if (typeof templateLang !== "string") {
+      data = templateLang;
+      templateLang = false;
     }
 
-    // if the user passes a string or other literal, remap to an object.
-    if (!isPlainObject(data)) {
-      data = {
-        _: data,
-      };
-    }
+    let fn = await compile.call(this, content, templateLang, {
+      templateConfig: opts.templateConfig || templateConfig,
+      extensionMap,
+    });
 
-    // save `page` for reuse
-    data.page = this.page;
-
-    return fn(data);
+    return renderShortcodeFn.call(this, fn, data);
   }
 
-  async function renderFileShortcodeFn(inputPath, data = {}, templateLang) {
-    let fn = await renderFile.call(
+  async function _renderFileShortcodeFn(inputPath, data = {}, templateLang) {
+    let fn = await compileFile.call(
       this,
       inputPath,
-      templateLang,
-      normalizeDirectories(eleventyConfig.dir),
       {
-        templateConfig,
+        templateConfig: opts.templateConfig || templateConfig,
         extensionMap,
-      }
+      },
+      templateLang
     );
 
-    if (fn === undefined) {
-      return;
-    } else if (typeof fn !== "function") {
-      throw new Error(
-        `The \`compile\` function did not return a function. Received ${fn}`
-      );
+    return renderShortcodeFn.call(this, fn, data);
+  }
+
+  // Render strings
+  if (opts.tagName) {
+    // use falsy to opt-out
+    eleventyConfig.addJavaScriptFunction(opts.tagName, _renderStringShortcodeFn);
+
+    eleventyConfig.addLiquidTag(opts.tagName, function (liquidEngine) {
+      return liquidTemplateTag(liquidEngine, opts.tagName);
+    });
+
+    eleventyConfig.addNunjucksTag(opts.tagName, function (nunjucksLib) {
+      return nunjucksTemplateTag(nunjucksLib, opts.tagName);
+    });
+  }
+
+  // Render File
+  // use `false` to opt-out
+  if (opts.tagNameFile) {
+    eleventyConfig.addAsyncShortcode(opts.tagNameFile, _renderFileShortcodeFn);
+  }
+}
+
+module.exports = EleventyPlugin;
+module.exports.File = compileFile;
+module.exports.String = compile;
+
+// Will re-use the same configuration instance both at a top level and across any nested renders
+class RenderManager {
+  constructor() {
+    this.templateConfig = new TemplateConfig(null, false);
+
+    // This is the only plugin running on the Edge
+    this.templateConfig.userConfig.addPlugin(EleventyPlugin, {
+      templateConfig: this.templateConfig,
+      accessGlobalData: true,
+    });
+  }
+
+  // `callback` is async-friendly but requires await upstream
+  config(callback) {
+    // run an extra `function(eleventyConfig)` configuration callbacks
+    if (callback && typeof callback === "function") {
+      return callback(this.templateConfig.userConfig);
     }
+  }
 
-    // if the user passes a string or other literal, remap to an object.
-    if (!isPlainObject(data)) {
-      data = {
-        _: data,
-      };
+  get initialGlobalData() {
+    if (!this._data) {
+      this._data = new TemplateDataInitialGlobalData(this.templateConfig);
     }
+    return this._data;
+  }
 
-    // save `page` for re-use
-    data.page = this.page;
-
-    return fn(data);
+  // because we don’t have access to the full data cascade—but
+  // we still want configuration data added via `addGlobalData`
+  async getData(...data) {
+    let globalData = await this.initialGlobalData.getData();
+    let merged = Merge({}, globalData, ...data);
+    return merged;
   }
 
-  // Render strings
-  eleventyConfig.addJavaScriptFunction(opts.tagName, renderStringShortcodeFn);
+  compile(content, templateLang, options = {}) {
+    // Missing here: extensionMap
+    options.templateConfig = this.templateConfig;
 
-  eleventyConfig.addLiquidTag(opts.tagName, function (liquidEngine) {
-    return liquidTemplateTag(liquidEngine, opts.tagName);
-  });
+    // We don’t need `compile.call(this)` here because the Edge always uses "liquid" as the template lang (instead of relying on this.page.templateSyntax)
+    // returns promise
+    return compile(content, templateLang, options);
+  }
 
-  eleventyConfig.addNunjucksTag(opts.tagName, function (nunjucksLib) {
-    return nunjucksTemplateTag(nunjucksLib, opts.tagName);
-  });
+  async render(fn, edgeData, buildTimeData) {
+    let mergedData = await this.getData(edgeData);
+    // Set .data for options.accessGlobalData feature
+    let context = {
+      data: mergedData,
+    };
 
-  // Render File
-  eleventyConfig.addJavaScriptFunction(opts.tagNameFile, renderFileShortcodeFn);
-  eleventyConfig.addLiquidShortcode(opts.tagNameFile, renderFileShortcodeFn);
-  eleventyConfig.addNunjucksAsyncShortcode(
-    opts.tagNameFile,
-    renderFileShortcodeFn
-  );
+    return renderShortcodeFn.call(context, fn, buildTimeData);
+  }
 }
 
-module.exports = EleventyPlugin;
+module.exports.RenderManager = RenderManager;

src/Plugins/ServerlessBundlerPlugin.js

@@ -5,114 +5,29 @@ const fs = require("fs");
 const isGlob = require("is-glob");
-const TOML = require("@iarna/toml");
 const copy = require("recursive-copy");
-const dependencyTree = require("@11ty/dependency-tree");
+const querystring = require("querystring");
 const { TemplatePath } = require("@11ty/eleventy-utils");
 
+const NetlifyRedirects = require("./Serverless/NetlifyRedirects");
+const { EleventyRequire } = require("../Util/Require");
+const DirContains = require("../Util/DirContains");
+const JavaScriptDependencies = require("../Util/JavaScriptDependencies");
 const deleteRequireCache = require("../Util/DeleteRequireCache");
 const debug = require("debug")("Eleventy:Serverless");
 
-function netlifyTomlRedirectHandler(name, outputMap, target) {
-  if (!target) {
-    throw new Error(
-      `Missing redirect target in Eleventy Serverless Bundler Plugin. Received ${target}`
-    );
-  }
-
-  let newRedirects = [];
-  for (let url in outputMap) {
-    newRedirects.push({
-      from: url,
-      to: `${target}${name}`,
-      status: 200,
-      force: true,
-      _generated_by_eleventy_serverless: name,
-    });
-  }
-
-  let configFilename = "./netlify.toml";
-  let cfg = {};
-  // parse existing netlify.toml
-  if (fs.existsSync(configFilename)) {
-    cfg = TOML.parse(fs.readFileSync(configFilename));
-  }
-  let cfgWithRedirects = addRedirectsWithoutDuplicates(name, cfg, newRedirects);
-
-  fs.writeFileSync(configFilename, TOML.stringify(cfgWithRedirects));
-  debug(
-    `Eleventy Serverless (${name}), writing (×${newRedirects.length}): ${configFilename}`
-  );
-}
-
 // Provider specific
 const redirectHandlers = {
   "netlify-toml": function (name, outputMap) {
-    return netlifyTomlRedirectHandler(name, outputMap, "/.netlify/functions/");
+    let r = new NetlifyRedirects(name);
+    return r.writeFile(outputMap, "/.netlify/functions/");
   },
   "netlify-toml-functions": function (name, outputMap) {
-    return netlifyTomlRedirectHandler(name, outputMap, "/.netlify/functions/");
+    let r = new NetlifyRedirects(name);
+    return r.writeFile(outputMap, "/.netlify/functions/");
   },
   "netlify-toml-builders": function (name, outputMap) {
-    return netlifyTomlRedirectHandler(name, outputMap, "/.netlify/builders/");
+    let r = new NetlifyRedirects(name);
+    return r.writeFile(outputMap, "/.netlify/builders/");
   },
 };
 
-function getNodeModulesList(files) {
-  let pkgs = new Set();
-
-  let jsFiles = files.filter((entry) => entry.endsWith(".js"));
-
-  for (let filepath of jsFiles) {
-    let modules = dependencyTree(filepath, {
-      nodeModuleNamesOnly: true,
-      allowNotFound: true, // TODO is this okay?
-    });
-
-    for (let name of modules) {
-      pkgs.add(name);
-    }
-  }
-
-  return Array.from(pkgs).sort();
-}
-
-function addRedirectsWithoutDuplicates(name, config, newRedirects) {
-  // keep non-generated redirects or those generated by a different function
-  let redirects = (config.redirects || []).filter((entry) => {
-    return (
-      !entry._generated_by_eleventy_serverless ||
-      entry._generated_by_eleventy_serverless !== name
-    );
-  });
-
-  // Sort for stable order
-  newRedirects.sort((a, b) => {
-    if (a.from < b.from) {
-      return -1;
-    } else if (a.from > b.from) {
-      return 1;
-    }
-    return 0;
-  });
-
-  for (let r of newRedirects) {
-    let found = false;
-    for (let entry of redirects) {
-      if (r.from === entry.from && r.to === entry.to) {
-        found = true;
-      }
-    }
-    if (!found) {
-      redirects.unshift(r);
-    }
-  }
-
-  if (redirects.length) {
-    config.redirects = redirects;
-  } else {
-    delete config.redirects;
-  }
-
-  return config;
-}
-
 class BundlerHelper {
@@ -142,12 +57,2 @@ constructor(name, options, eleventyConfig) {
 
-  copyFile(fullPath, outputFilename) {
-    debug(
-      `Eleventy Serverless: Copying ${fullPath} to ${this.getOutputPath(
-        outputFilename
-      )}`
-    );
-    fs.copyFileSync(fullPath, this.getOutputPath(outputFilename));
-    this.copyCount++;
-  }
-
   recursiveCopy(src, dest, options = {}) {
@@ -160,2 +65,4 @@ // skip this one if not a glob and doesn’t exist
     let finalDest = this.getOutputPath(dest || src);
+    debug(`Eleventy Serverless: Copying ${src} to ${finalDest}`);
+
     return copy(
@@ -167,3 +74,3 @@ src,
           overwrite: true,
-          dot: true,
+          dot: false,
           junk: false,
@@ -181,4 +88,8 @@ results: false,
   writeBundlerDependenciesFile(filename, deps = []) {
+    let fullPath = this.getOutputPath(filename);
+    if (deps.length === 0 && fs.existsSync(fullPath)) {
+      return;
+    }
+
     let modules = deps.map((name) => `require("${name}");`);
-    let fullPath = this.getOutputPath(filename);
     fs.writeFileSync(fullPath, modules.join("\n"));
@@ -192,3 +103,10 @@ this.copyCount++;
   writeDependencyEntryFile() {
-    // we write this even when disabled because the serverless function expects it
+    // ensure these exist for requiring
+    if (this.options.copyEnabled) {
+      this.writeBundlerDependenciesFile("eleventy-app-config-modules.js");
+      this.writeBundlerDependenciesFile("eleventy-app-globaldata-modules.js");
+      this.writeBundlerDependenciesFile("eleventy-app-dirdata-modules.js");
+    }
+
+    // we write these even when copy is disabled because the serverless function expects it
     this.writeBundlerDependenciesFile(
@@ -200,2 +118,3 @@ "eleventy-bundler-modules.js",
             "./eleventy-app-globaldata-modules.js",
+            "./eleventy-app-dirdata-modules.js",
           ]
@@ -206,3 +125,12 @@ : []
 
-  writeDependencyConfigFile(configPath) {
+  async copyFileList(fileList) {
+    let promises = [];
+    for (let file of fileList) {
+      promises.push(this.recursiveCopy(file));
+    }
+    return Promise.all(promises);
+  }
+
+  // Does *not* copy the original files (only the deps)
+  async processJavaScriptFiles(files, dependencyFilename) {
     if (!this.options.copyEnabled) {
@@ -212,35 +140,45 @@ return;
 
-    let modules = getNodeModulesList([configPath]);
+    let nodeModules = JavaScriptDependencies.getDependencies(files, true);
     this.writeBundlerDependenciesFile(
-      "eleventy-app-config-modules.js",
-      modules.filter(
-        (name) => this.options.excludeDependencies.indexOf(name) === -1
-      )
+      dependencyFilename,
+      nodeModules.filter((name) => this.options.excludeDependencies.indexOf(name) === -1)
     );
+
+    let localModules = JavaScriptDependencies.getDependencies(files, false);
+    // promise
+    return this.copyFileList(localModules);
   }
 
-  writeDependencyGlobalDataFile(globalDataFileList) {
-    if (!this.options.copyEnabled) {
-      return;
+  // https://github.com/11ty/eleventy/issues/2422
+  // This behavior is dictated by AWS Lambda https://aws.amazon.com/blogs/compute/support-for-multi-value-parameters-in-amazon-api-gateway/
+  // Duplicate keys are provided as a single comma separated string
+  getSingleValueQueryParams(searchParams) {
+    let obj = {};
+    for (let [key, value] of searchParams) {
+      if (!obj[key]) {
+        obj[key] = value;
+      } else {
+        obj[key] += `, ${value}`;
+      }
     }
+    return obj;
+  }
 
-    let modules = getNodeModulesList(globalDataFileList);
-    this.writeBundlerDependenciesFile(
-      "eleventy-app-globaldata-modules.js",
-      modules.filter(
-        (name) => this.options.excludeDependencies.indexOf(name) === -1
-      )
-    );
+  // https://github.com/11ty/eleventy/issues/2422
+  // This behavior is dictated by AWS Lambda https://aws.amazon.com/blogs/compute/support-for-multi-value-parameters-in-amazon-api-gateway/
+  // Duplicate keys are combined into one array of values
+  getMultiValueQueryParams(searchParams) {
+    return querystring.parse(searchParams.toString());
   }
 
-  browserSyncMiddleware() {
+  serverMiddleware() {
     let serverlessFilepath = TemplatePath.addLeadingDotSlash(
       path.join(TemplatePath.getWorkingDir(), this.dir, "index")
     );
-    deleteRequireCache(TemplatePath.absolutePath(serverlessFilepath));
 
     return async function EleventyServerlessMiddleware(req, res, next) {
-      let serverlessFunction = require(serverlessFilepath);
+      deleteRequireCache(serverlessFilepath);
+
+      let serverlessFunction = EleventyRequire(serverlessFilepath);
       let url = new URL(req.url, "http://localhost/"); // any domain will do here, we just want the searchParams
-      let queryParams = Object.fromEntries(url.searchParams);
 
@@ -252,5 +190,7 @@ let start = new Date();
         rawUrl: url.toString(),
+
         // @netlify/functions builder overwrites these to {} intentionally
         // See https://github.com/netlify/functions/issues/38
-        queryStringParameters: queryParams,
+        queryStringParameters: this.getSingleValueQueryParams(url.searchParams),
+        multiValueQueryStringParameters: this.getMultiValueQueryParams(url.searchParams),
       });
@@ -265,3 +205,2 @@
       res.write(result.body);
-      res.end();
 
@@ -271,2 +210,11 @@ this.eleventyConfig.logger.forceLog(
       );
+
+      // eleventy-dev-server 1.0.0-canary.10 and newer
+      if ("_shouldForceEnd" in res) {
+        res._shouldForceEnd = true;
+        next();
+      } else {
+        // eleventy-dev-server 1.0.0-canary.9 and below
+        res.end();
+      }
     }.bind(this);
@@ -291,6 +239,3 @@ }
       contents = contents.replace(/\%\%NAME\%\%/g, this.name);
-      contents = contents.replace(
-        /\%\%FUNCTIONS_DIR\%\%/g,
-        this.options.functionsDir
-      );
+      contents = contents.replace(/\%\%FUNCTIONS_DIR\%\%/g, this.options.functionsDir);
       return fsp.writeFile(filepath, contents);
@@ -326,5 +271,3 @@ }
   if (!options.name) {
-    throw new Error(
-      "Serverless addPlugin second argument options object must have a name."
-    );
+    throw new Error("Serverless addPlugin second argument options object must have a name.");
   }
@@ -335,4 +278,4 @@
 
-    eleventyConfig.setBrowserSyncConfig({
-      middleware: [helper.browserSyncMiddleware()],
+    eleventyConfig.setServerOptions({
+      middleware: [helper.serverMiddleware()],
     });
@@ -362,6 +305,3 @@
           } else {
-            debug(
-              "Ignored extra copy %o (needs to be a string or a {from: '', to: ''})",
-              cp
-            );
+            debug("Ignored extra copy %o (needs to be a string or a {from: '', to: ''})", cp);
           }
@@ -382,13 +322,19 @@ }
 
-      if (options.copyEnabled) {
-        helper.copyFile(env.config, "eleventy.config.js");
+      if (!options.copyEnabled) {
+        return;
+      }
 
-        helper.writeDependencyConfigFile(env.config);
-      }
+      await helper.recursiveCopy(env.config, "eleventy.config.js");
+      await helper.processJavaScriptFiles([env.config], "eleventy-app-config-modules.js");
     });
 
-    eleventyConfig.on("eleventy.globalDataFiles", (fileList) => {
-      helper.writeDependencyGlobalDataFile(fileList);
+    eleventyConfig.on("eleventy.globalDataFiles", async (fileList) => {
+      if (!options.copyEnabled) {
+        return;
+      }
+      // Note that originals are copied in `eleventy.directories` event below
+      await helper.processJavaScriptFiles(fileList, "eleventy-app-globaldata-modules.js");
     });
 
+    // directory data files only
     eleventyConfig.on("eleventy.dataFiles", async (fileList) => {
@@ -399,7 +345,4 @@ if (!options.copyEnabled) {
 
-      let promises = [];
-      for (let file of fileList) {
-        promises.push(helper.recursiveCopy(file));
-      }
-      await Promise.all(promises);
+      await helper.copyFileList(fileList);
+      await helper.processJavaScriptFiles(fileList, "eleventy-app-dirdata-modules.js");
     });
@@ -410,5 +353,12 @@
       if (options.copyEnabled) {
-        promises.push(helper.recursiveCopy(dirs.data));
-        promises.push(helper.recursiveCopy(dirs.includes));
-        if (dirs.layouts) {
+        promises.push(helper.recursiveCopy(dirs.input));
+
+        if (!DirContains(dirs.input, dirs.data)) {
+          promises.push(helper.recursiveCopy(dirs.data));
+        }
+        if (!DirContains(dirs.input, dirs.includes)) {
+          promises.push(helper.recursiveCopy(dirs.includes));
+        }
+        if (dirs.layouts && !DirContains(dirs.input, dirs.layouts)) {
+          // TODO avoid copy if dirs.layouts is in dirs.input
           promises.push(helper.recursiveCopy(dirs.layouts));
@@ -472,5 +422,3 @@ }
       fs.writeFileSync(filename, JSON.stringify(outputMap, null, 2));
-      debug(
-        `Eleventy Serverless (${options.name}), writing (×${mapEntryCount}): ${filename}`
-      );
+      debug(`Eleventy Serverless (${options.name}), writing (×${mapEntryCount}): ${filename}`);
       this.copyCount++;
@@ -480,6 +428,3 @@
       if (options.copyEnabled && options.redirects) {
-        if (
-          typeof options.redirects === "string" &&
-          redirectHandlers[options.redirects]
-        ) {
+        if (typeof options.redirects === "string" && redirectHandlers[options.redirects]) {
           redirectHandlers[options.redirects](options.name, outputMap);
@@ -490,9 +435,2 @@ } else if (typeof options.redirects === "function") {
       }
-
-      if (options.copyEnabled && mapEntryCount > 0) {
-        // Copy templates to bundle folder
-        for (let url in outputMap) {
-          helper.recursiveCopy(outputMap[url]);
-        }
-      }
     });
@@ -499,0 +437,0 @@ }

src/Serverless.js

@@ -7,2 +7,3 @@ const path = require("path");
 const Eleventy = require("./Eleventy");
+const normalizeServerlessUrl = require("./Util/NormalizeServerlessUrl");
 const deleteRequireCache = require("./Util/DeleteRequireCache");
@@ -25,5 +26,3 @@ const debug = require("debug")("Eleventy:Serverless");
     if (!this.path) {
-      throw new Error(
-        "`path` must exist in the options argument in Eleventy Serverless."
-      );
+      throw new Error("`path` must exist in the options argument in Eleventy Serverless.");
     }
@@ -44,12 +43,24 @@
         functionsDir: "functions/",
+
         matchUrlToPattern(path, urlToCompare) {
+          urlToCompare = normalizeServerlessUrl(urlToCompare);
+
           let fn = match(urlToCompare, { decode: decodeURIComponent });
           return fn(path);
         },
+
         // Query String Parameters
         query: {},
+
+        // Configuration callback
+        config: function (eleventyConfig) {},
+
+        // Is serverless build scoped to a single template?
+        // Use `false` to make serverless more collections-friendly (but slower!)
+        // With `false` you don’t need precompiledCollections.
+        // Works great with on-demand builders
+        singleTemplateScope: true,
+
         // Inject shared collections
         precompiledCollections: {},
-        // Configuration callback
-        config: function (eleventyConfig) {},
       },
@@ -63,8 +74,3 @@ options
   initializeEnvironmentVariables() {
-    // set and delete env variables to make it work the same on --serve
-    this.serverlessEnvironmentVariableAlreadySet =
-      !!process.env.ELEVENTY_SERVERLESS;
-    if (!this.serverlessEnvironmentVariableAlreadySet) {
-      process.env.ELEVENTY_SERVERLESS = true;
-    }
+    this.serverlessEnvironmentVariableAlreadySet = !!process.env.ELEVENTY_SERVERLESS;
   }
@@ -93,5 +99,3 @@
 
-    throw new Error(
-      `Couldn’t find the "${dir}" directory. Looked in: ${paths}`
-    );
+    throw new Error(`Couldn’t find the "${dir}" directory. Looked in: ${paths}`);
   }
@@ -101,10 +105,8 @@
     let fullPath = TemplatePath.absolutePath(this.dir, this.mapFilename);
-    debug(
-      `Including content map (maps output URLs to input files) from ${fullPath}`
-    );
+    debug(`Including content map (maps output URLs to input files) from ${fullPath}`);
+
     // TODO dedicated reset method, don’t delete this every time
     deleteRequireCache(fullPath);
 
-    let mapContent = require(fullPath);
-    return mapContent;
+    return require(fullPath);
   }
@@ -115,7 +117,7 @@
     debug(`Including config info file from ${fullPath}`);
+
     // TODO dedicated reset method, don’t delete this every time
     deleteRequireCache(fullPath);
 
-    let configInfo = require(fullPath);
-    return configInfo;
+    return require(fullPath);
   }
@@ -170,6 +172,3 @@
 
-    let inputDir =
-      this.options.input ||
-      this.options.inputDir ||
-      this.getConfigInfo().dir.input;
+    let inputDir = this.options.input || this.options.inputDir || this.getConfigInfo().dir.input;
     let configPath = path.join(this.dir, this.configFilename);
@@ -180,5 +179,3 @@ let { pathParams, inputPath } = this.matchUrlPattern(this.path);
       let err = new Error(
-        `No matching URL found for ${this.path} in ${JSON.stringify(
-          this.getContentMap()
-        )}`
+        `No matching URL found for ${this.path} in ${JSON.stringify(this.getContentMap())}`
       );
@@ -198,6 +195,10 @@ err.httpStatusCode = 404;
 
-    // TODO (@zachleat) change to use this hook: https://github.com/11ty/eleventy/issues/1957
     this.initializeEnvironmentVariables();
 
-    let elev = new Eleventy(this.options.input || inputPath, null, {
+    let isScoped = !!this.options.singleTemplateScope;
+    let projectInput = isScoped ? this.options.input || inputPath : inputDir;
+
+    let elev = new Eleventy(projectInput, null, {
+      // https://github.com/11ty/eleventy/issues/1957
+      isServerless: true,
       configPath,
@@ -207,5 +208,3 @@ inputDir,
         if (Object.keys(this.options.precompiledCollections).length > 0) {
-          eleventyConfig.setPrecompiledCollections(
-            this.options.precompiledCollections
-          );
+          eleventyConfig.setPrecompiledCollections(this.options.precompiledCollections);
         }
@@ -227,10 +226,17 @@
 
+    if (!isScoped) {
+      elev.setIncrementalFile(this.options.input || inputPath);
+    }
+
     let json = await elev.toJSON();
 
-    // TODO (@zachleat)  https://github.com/11ty/eleventy/issues/1957
+    // https://github.com/11ty/eleventy/issues/1957
     this.deleteEnvironmentVariables();
 
-    let filtered = json.filter((entry) => {
-      return entry.inputPath === inputPath;
-    });
+    let filtered = [];
+    if (Array.isArray(json)) {
+      filtered = json.filter((entry) => {
+        return entry.inputPath === inputPath;
+      });
+    }
 
@@ -237,0 +243,0 @@ if (!filtered.length) {

src/Template.js

@@ -9,10 +9,10 @@ const fs = require("graceful-fs");
 const normalize = require("normalize-path");
-const lodashGet = require("lodash/get");
-const lodashSet = require("lodash/set");
+const lodashGet = require("lodash.get");
+const lodashSet = require("lodash.set");
 const { DateTime } = require("luxon");
-const { TemplatePath } = require("@11ty/eleventy-utils");
+const { TemplatePath, isPlainObject } = require("@11ty/eleventy-utils");
 
-const isPlainObject = require("./Util/IsPlainObject");
 const ConsoleLogger = require("./Util/ConsoleLogger");
 const getDateFromGitLastUpdated = require("./Util/DateGitLastUpdated");
+const getDateFromGitFirstAdded = require("./Util/DateGitFirstAdded");
 
@@ -38,10 +38,3 @@ const TemplateData = require("./TemplateData");
 class Template extends TemplateContent {
-  constructor(
-    templatePath,
-    inputDir,
-    outputDir,
-    templateData,
-    extensionMap,
-    config
-  ) {
+  constructor(templatePath, inputDir, outputDir, templateData, extensionMap, config) {
     debugDev("new Template(%o)", templatePath);
@@ -65,18 +58,10 @@ super(templatePath, inputDir, config);
     this.transforms = [];
-    this.templateData = templateData;
-    if (this.templateData) {
-      this.templateData.setInputDir(this.inputDir);
-    }
-    this.paginationData = {};
 
+    this.setTemplateData(templateData);
+
     this.isVerbose = true;
     this.isDryRun = false;
     this.writeCount = 0;
-    this.skippedCount = 0;
-    this.wrapWithLayouts = true;
-    this.fileSlug = new TemplateFileSlug(
-      this.inputPath,
-      this.inputDir,
-      this.extensionMap
-    );
+
+    this.fileSlug = new TemplateFileSlug(this.inputPath, this.inputDir, this.extensionMap);
     this.fileSlugStr = this.fileSlug.getSlug();
@@ -93,2 +78,9 @@ this.filePathStem = this.fileSlug.getFullPathWithoutExtension();
 
+  setTemplateData(templateData) {
+    this.templateData = templateData;
+    if (this.templateData) {
+      this.templateData.setInputDir(this.inputDir);
+    }
+  }
+
   get logger() {
@@ -107,2 +99,25 @@ if (!this._logger) {
 
+  setRenderableOverride(renderableOverride) {
+    this.behavior.setRenderableOverride(renderableOverride);
+  }
+
+  reset() {
+    this.writeCount = 0;
+  }
+
+  resetCaches(types) {
+    types = this.getResetTypes(types);
+
+    super.resetCaches(types);
+
+    if (types.data) {
+      delete this._dataCache;
+    }
+
+    if (types.render) {
+      delete this._cacheRenderedContent;
+      delete this._cacheFinalContent;
+    }
+  }
+
   setOutputFormat(to) {
@@ -118,2 +133,7 @@ this.outputFormat = to;
 
+  setDryRunViaIncremental() {
+    this.isDryRun = true;
+    this.isIncremental = true;
+  }
+
   setDryRun(isDryRun) {
@@ -123,6 +143,2 @@ this.isDryRun = !!isDryRun;
 
-  setWrapWithLayouts(wrap) {
-    this.wrapWithLayouts = wrap;
-  }
-
   setExtraOutputSubdirectory(dir) {
@@ -137,22 +153,11 @@ this.extraOutputSubdirectory = dir + "/";
   getLayout(layoutKey) {
-    if (!this._layout || layoutKey !== this._layoutKey) {
-      this._layoutKey = layoutKey;
-      this._layout = TemplateLayout.getTemplate(
-        layoutKey,
-        this.getInputDir(),
-        this.config,
-        this.extensionMap
-      );
-    }
-    return this._layout;
+    // already cached downstream in TemplateLayout -> TemplateCache
+    return TemplateLayout.getTemplate(
+      layoutKey,
+      this.getInputDir(),
+      this.config,
+      this.extensionMap
+    );
   }
 
-  async _testGetLayoutChain() {
-    if (!this._layout) {
-      await this.getData();
-    }
-
-    return this._layout._testGetLayoutChain();
-  }
-
   get baseFile() {
@@ -180,3 +185,3 @@ return this.extensionMap.removeTemplateExtension(this.parsed.base);
 
-  initServerlessUrlsForEmptyPaginationTemplates(permalinkValue) {
+  async initServerlessUrlsForEmptyPaginationTemplates(permalinkValue) {
     if (isPlainObject(permalinkValue)) {
@@ -192,11 +197,9 @@ let buildlessPermalink = Object.assign({}, permalinkValue);
 
-  _getRawPermalinkInstance(permalinkValue) {
-    let perm = new TemplatePermalink(
-      permalinkValue,
-      this.extraOutputSubdirectory
-    );
+  async _getRawPermalinkInstance(permalinkValue) {
+    let perm = new TemplatePermalink(permalinkValue, this.extraOutputSubdirectory);
+    perm.setUrlTransforms(this.config.urlTransforms);
+
     if (this.templateData) {
-      perm.setServerlessPathData(this.templateData.getServerlessPathData());
+      perm.setServerlessPathData(await this.templateData.getServerlessPathData());
     }
-
     this.behavior.setFromPermalink(perm);
@@ -210,3 +213,3 @@ this.serverlessUrls = perm.getServerlessUrls();
     if (!data) {
-      data = await this.getData();
+      throw new Error("data argument missing in Template->_getLink");
     }
@@ -222,6 +225,3 @@
       permalinkValue = permalink;
-    } else if (
-      permalink &&
-      (!this.config.dynamicPermalinks || data.dynamicPermalink === false)
-    ) {
+    } else if (permalink && (!this.config.dynamicPermalinks || data.dynamicPermalink === false)) {
       debugDev("Not using dynamic permalinks, using %o", permalink);
@@ -240,7 +240,3 @@ permalinkValue = permalink;
             promises.push(
-              Promise.all(
-                [...permalink[key]].map((entry) =>
-                  super.renderPermalink(entry, data)
-                )
-              )
+              Promise.all([...permalink[key]].map((entry) => super.renderPermalink(entry, data)))
             );
@@ -270,8 +266,3 @@ } else {
       permalinkValue = await super.renderPermalink(permalink, data);
-      debug(
-        "Rendering permalink for %o: %s becomes %o",
-        this.inputPath,
-        permalink,
-        permalinkValue
-      );
+      debug("Rendering permalink for %o: %s becomes %o", this.inputPath, permalink, permalinkValue);
       debugDev("Permalink rendered with data: %o", data);
@@ -284,7 +275,3 @@ }
       if (typeof permalinkCompilation === "function") {
-        let ret = await this._renderFunction(
-          permalinkCompilation,
-          permalinkValue,
-          this.inputPath
-        );
+        let ret = await this._renderFunction(permalinkCompilation, permalinkValue, this.inputPath);
         if (ret !== undefined) {
@@ -307,3 +294,3 @@ if (typeof ret === "function") {
     // No `permalink` specified in data cascade, do the default
-    return TemplatePermalink.generate(
+    let p = TemplatePermalink.generate(
       this.getTemplateSubfolder(),
@@ -315,2 +302,4 @@ this.baseFile,
     );
+    p.setUrlTransforms(this.config.urlTransforms);
+    return p;
   }
@@ -321,5 +310,3 @@
       // TODO this only works with immediate front matter and not data files
-      this._usePermalinkRoot = (await this.getFrontMatterData())[
-        this.config.keys.permalinkRoot
-      ];
+      this._usePermalinkRoot = (await this.getFrontMatterData())[this.config.keys.permalinkRoot];
     }
@@ -332,2 +319,3 @@
   async getOutputLocations(data) {
+    this.bench.get("(count) getOutputLocations").incrementCount();
     let link = await this._getLink(data);
@@ -349,4 +337,6 @@
 
+  // This is likely now a test-only method
   // Preferred to use the singular `getOutputLocations` above.
   async getRawOutputPath(data) {
+    this.bench.get("(count) getRawOutputPath").incrementCount();
     let link = await this._getLink(data);
@@ -358,2 +348,3 @@ return link.toOutputPath();
   async getOutputHref(data) {
+    this.bench.get("(count) getOutputHref").incrementCount();
     let link = await this._getLink(data);
@@ -365,2 +356,3 @@ return link.toHref();
   async getOutputPath(data) {
+    this.bench.get("(count) getOutputPath").incrementCount();
     let link = await this._getLink(data);
@@ -373,33 +365,2 @@ if (await this.usePermalinkRoot()) {
 
-  setPaginationData(paginationData) {
-    this.paginationData = paginationData;
-  }
-
-  async mapDataAsRenderedTemplates(data, templateData) {
-    // function supported in JavaScript type
-    if (typeof data === "string" || typeof data === "function") {
-      debug("rendering data.renderData for %o", this.inputPath);
-      // bypassMarkdown
-      let str = await super.render(data, templateData, true);
-      return str;
-    } else if (Array.isArray(data)) {
-      return Promise.all(
-        data.map((item) => this.mapDataAsRenderedTemplates(item, templateData))
-      );
-    } else if (isPlainObject(data)) {
-      let obj = {};
-      await Promise.all(
-        Object.keys(data).map(async (value) => {
-          obj[value] = await this.mapDataAsRenderedTemplates(
-            data[value],
-            templateData
-          );
-        })
-      );
-      return obj;
-    }
-
-    return data;
-  }
-
   async _testGetAllLayoutFrontMatterData() {
@@ -415,56 +376,45 @@ let frontMatterData = await this.getFrontMatterData();
   async getData() {
-    if (!this.dataCache) {
-      debugDev("%o getData()", this.inputPath);
-      let localData = {};
-      let globalData = {};
+    if (this._dataCache) {
+      return this._dataCache;
+    }
 
-      if (this.templateData) {
-        localData = await this.templateData.getTemplateDirectoryData(
-          this.inputPath
-        );
-        globalData = await this.templateData.getGlobalData(this.inputPath);
-        debugDev(
-          "%o getData() getTemplateDirectoryData and getGlobalData",
-          this.inputPath
-        );
-      }
+    debugDev("%o getData", this.inputPath);
+    let localData = {};
+    let globalData = {};
 
-      let frontMatterData = await this.getFrontMatterData();
-      let layoutKey =
-        frontMatterData[this.config.keys.layout] ||
-        localData[this.config.keys.layout] ||
-        globalData[this.config.keys.layout];
+    if (this.templateData) {
+      localData = await this.templateData.getTemplateDirectoryData(this.inputPath);
+      globalData = await this.templateData.getGlobalData(this.inputPath);
+      debugDev("%o getData getTemplateDirectoryData and getGlobalData", this.inputPath);
+    }
 
-      // Layout front matter data
-      let mergedLayoutData = {};
-      if (layoutKey) {
-        let layout = this.getLayout(layoutKey);
+    let frontMatterData = await this.getFrontMatterData();
+    let layoutKey =
+      frontMatterData[this.config.keys.layout] ||
+      localData[this.config.keys.layout] ||
+      globalData[this.config.keys.layout];
 
-        mergedLayoutData = await layout.getData();
-        debugDev(
-          "%o getData() get merged layout chain front matter",
-          this.inputPath
-        );
-      }
+    // Layout front matter data
+    let mergedLayoutData = {};
+    if (layoutKey) {
+      let layout = this.getLayout(layoutKey);
 
-      let mergedData = TemplateData.mergeDeep(
-        this.config,
-        {},
-        globalData,
-        mergedLayoutData,
-        localData,
-        frontMatterData
-      );
-      mergedData = await this.addPageDate(mergedData);
-      mergedData = this.addPageData(mergedData);
-      debugDev("%o getData() mergedData", this.inputPath);
-
-      this.dataCache = mergedData;
+      mergedLayoutData = await layout.getData();
+      debugDev("%o getData merged layout chain front matter", this.inputPath);
     }
 
-    // Don’t deep merge pagination data! See https://github.com/11ty/eleventy/issues/147#issuecomment-440802454
-    return Object.assign(
-      TemplateData.mergeDeep(this.config, {}, this.dataCache),
-      this.paginationData
+    let mergedData = TemplateData.mergeDeep(
+      this.config,
+      {},
+      globalData,
+      mergedLayoutData,
+      localData,
+      frontMatterData
     );
+    mergedData = await this.addPageDate(mergedData);
+    mergedData = this.addPageData(mergedData);
+    debugDev("%o getData mergedData", this.inputPath);
+
+    this._dataCache = mergedData;
+    return mergedData;
   }
@@ -501,2 +451,5 @@
     data.page.outputFileExtension = this.engine.defaultTemplateFileExtension;
+    data.page.templateSyntax = this.templateRender.getEnginesList(
+      data[this.config.keys.engineOverride]
+    );
 
@@ -506,2 +459,3 @@ return data;
 
+  // TODO This isn’t used any more, see `renderPageEntry`
   async renderLayout(tmpl, tmplData) {
@@ -512,22 +466,24 @@ let layoutKey = tmplData[tmpl.config.keys.layout];
 
-    // TODO reuse templateContent from templateMap
-    let templateContent = await super.render(
-      await this.getPreRender(),
-      tmplData
-    );
+    let templateContent = await super.render(await this.getPreRender(), tmplData);
+
     return layout.render(tmplData, templateContent);
   }
 
-  async _testRenderWithoutLayouts(data) {
-    this.setWrapWithLayouts(false);
-    let ret = await this.render(data);
-    this.setWrapWithLayouts(true);
-    return ret;
+  async renderDirect(str, data, bypassMarkdown) {
+    return super.render(str, data, bypassMarkdown);
   }
 
-  // Used only by tests
-  async renderContent(str, data, bypassMarkdown) {
-    return super.render(str, data, bypassMarkdown);
+  // This is the primary render mechanism, called via TemplateMap->populateContentDataInMap
+  async renderWithoutLayout(data) {
+    if (this._cacheRenderedContent) {
+      return this._cacheRenderedContent;
+    }
+
+    let content = await this.getPreRender();
+    let renderedContent = await this.renderDirect(content, data);
+    this._cacheRenderedContent = renderedContent;
+    return renderedContent;
   }
 
+  // TODO This isn’t used any more, see `renderPageEntry`
   async render(data) {
@@ -539,15 +495,7 @@ debugDev("%o render()", this.inputPath);
 
-    if (!this.wrapWithLayouts && data[this.config.keys.layout]) {
-      debugDev("Template.render is bypassing layouts for %o.", this.inputPath);
-    }
-
-    if (this.wrapWithLayouts && data[this.config.keys.layout]) {
-      debugDev(
-        "Template.render found layout: %o",
-        data[this.config.keys.layout]
-      );
+    if (data[this.config.keys.layout]) {
       return this.renderLayout(this, data);
     } else {
-      debugDev("Template.render renderContent for %o", this.inputPath);
-      return super.render(await this.getPreRender(), data);
+      debugDev("Template.render renderDirect for %o", this.inputPath);
+      return this.renderWithoutLayout(data);
     }
@@ -560,3 +508,6 @@ }
 
-  async runLinters(str, inputPath, outputPath) {
+  async runLinters(str, page) {
+    let { inputPath, outputPath, url } = page;
+    let pageData = page.data.page;
+
     for (let linter of this.linters) {
@@ -568,2 +519,4 @@ // these can be asynchronous but no guarantee of order when they run
           outputPath,
+          url,
+          page: pageData,
         },
@@ -584,3 +537,6 @@ str,
 
-  async runTransforms(str, inputPath, outputPath) {
+  async runTransforms(str, page) {
+    let { inputPath, outputPath, url } = page;
+    let pageData = page.data.page;
+
     for (let { callback, name } of this.transforms) {
@@ -593,2 +549,4 @@ try {
             outputPath,
+            url,
+            page: pageData,
           },
@@ -625,8 +583,3 @@ str,
         keys.push(key);
-        this._addComputedEntry(
-          computedData,
-          obj[key],
-          keys.join("."),
-          declaredDependencies
-        );
+        this._addComputedEntry(computedData, obj[key], keys.join("."), declaredDependencies);
       }
@@ -637,3 +590,3 @@ } else if (typeof obj === "string") {
         async (innerData) => {
-          return await this.renderComputedData(obj, innerData, true);
+          return await this.renderComputedData(obj, innerData);
         },
@@ -650,9 +603,10 @@ declaredDependencies,
   async addComputedData(data) {
-    // will _not_ consume renderData
-    this.computedData = new ComputedData(this.config);
+    if (this.config.keys.computed in data) {
+      this.computedData = new ComputedData(this.config);
 
-    if (this.config.keys.computed in data) {
       // Note that `permalink` is only a thing that gets consumed—it does not go directly into generated data
       // this allows computed entries to use page.url or page.outputPath and they’ll be resolved properly
 
+      // TODO Room for optimization here—we don’t need to recalculate `getOutputHref` and `getOutputPath`
+      // TODO Why are these using addTemplateString instead of add
       this.computedData.addTemplateString(
@@ -673,6 +627,3 @@ "page.url",
       // actually add the computed data
-      this._addComputedEntry(
-        this.computedData,
-        data[this.config.keys.computed]
-      );
+      this._addComputedEntry(this.computedData, data[this.config.keys.computed]);
 
@@ -694,2 +645,7 @@ // limited run of computed data—save the stuff that relies on collections for later.
 
+      // pagination will already have these set via Pagination->getPageTemplates
+      if (data.page.url && data.page.outputPath) {
+        return;
+      }
+
       let { href, path } = await this.getOutputLocations(data);
@@ -699,15 +655,61 @@ data.page.url = href;
     }
+  }
 
-    // Deprecated, use eleventyComputed instead.
-    if ("renderData" in data) {
-      data.renderData = await this.mapDataAsRenderedTemplates(
-        data.renderData,
-        data
-      );
+  // Computed data consuming collections!
+  async resolveRemainingComputedData(data) {
+    // If it doesn’t exist, computed data is not used for this template
+    if (this.computedData) {
+      debug("Second round of computed data for %o", this.inputPath);
+      await this.computedData.processRemainingData(data);
     }
   }
 
-  async resolveRemainingComputedData(data) {
-    debug("Second round of computed data for %o", this.inputPath);
-    await this.computedData.processRemainingData(data);
+  static augmentWithTemplateContentProperty(obj) {
+    return Object.defineProperties(obj, {
+      checkTemplateContent: {
+        enumerable: false,
+        writable: true,
+        value: true,
+      },
+      _templateContent: {
+        enumerable: false,
+        writable: true,
+        value: undefined,
+      },
+      templateContent: {
+        enumerable: true,
+        set(content) {
+          if (content === undefined) {
+            this.checkTemplateContent = false;
+          }
+          this._templateContent = content;
+        },
+        get() {
+          if (this.checkTemplateContent && this._templateContent === undefined) {
+            if (this.template.behavior.isRenderable()) {
+              // should at least warn here
+              throw new TemplateContentPrematureUseError(
+                `Tried to use templateContent too early on ${this.inputPath}${
+                  this.pageNumber ? ` (page ${this.pageNumber})` : ""
+                }`
+              );
+            } else {
+              throw new TemplateContentUnrenderedTemplateError(
+                `Tried to use templateContent on unrendered template. You need a valid permalink (or permalink object) to use templateContent on ${
+                  this.inputPath
+                }${this.pageNumber ? ` (page ${this.pageNumber})` : ""}`
+              );
+            }
+          }
+          return this._templateContent;
+        },
+      },
+      // Alias for templateContent for consistency
+      content: {
+        enumerable: true,
+        get() {
+          return this.templateContent;
+        },
+      },
+    });
   }
@@ -717,99 +719,48 @@
     // no pagination with permalink.serverless
-    let hasPagination = Pagination.hasPagination(data);
-
-    if (!hasPagination) {
+    if (!Pagination.hasPagination(data)) {
       await this.addComputedData(data);
 
-      return [
-        {
-          template: this,
-          inputPath: this.inputPath,
-          fileSlug: this.fileSlugStr,
-          filePathStem: this.filePathStem,
-          data: data,
-          date: data.page.date,
-          outputPath: data.page.outputPath,
-          url: data.page.url,
-          checkTemplateContent: true,
-          set templateContent(content) {
-            if (content === undefined) {
-              this.checkTemplateContent = false;
-            }
-            this._templateContent = content;
-          },
-          get templateContent() {
-            if (
-              this.checkTemplateContent &&
-              this._templateContent === undefined
-            ) {
-              if (this.template.behavior.isRenderable()) {
-                // should at least warn here
-                throw new TemplateContentPrematureUseError(
-                  `Tried to use templateContent too early (${this.inputPath})`
-                );
-              } else {
-                throw new TemplateContentUnrenderedTemplateError(
-                  `Tried to use templateContent on unrendered template. You need a valid permalink (or permalink object) to use templateContent on ${this.inputPath}`
-                );
-              }
-            }
-            return this._templateContent;
-          },
-        },
-      ];
+      let obj = {
+        template: this, // not on the docs but folks are relying on it
+        data,
+
+        page: data.page,
+        inputPath: this.inputPath,
+        fileSlug: this.fileSlugStr,
+        filePathStem: this.filePathStem,
+        date: data.page.date,
+        outputPath: data.page.outputPath,
+        url: data.page.url,
+      };
+
+      obj = Template.augmentWithTemplateContentProperty(obj);
+
+      return [obj];
     } else {
       // needs collections for pagination items
       // but individual pagination entries won’t be part of a collection
-      this.paging = new Pagination(data, this.config);
-      this.paging.setTemplate(this);
+      this.paging = new Pagination(this, data, this.config);
 
       let pageTemplates = await this.paging.getPageTemplates();
-
       return await Promise.all(
-        pageTemplates.map(async (page, pageNumber) => {
-          // TODO get smarter with something like Object.assign(data, override);
-          let pageData = Object.assign({}, await page.getData());
+        pageTemplates.map(async (pageEntry, pageNumber) => {
+          await pageEntry.template.addComputedData(pageEntry.data);
 
-          await page.addComputedData(pageData);
+          let obj = {
+            template: pageEntry.template, // not on the docs but folks are relying on it
+            pageNumber: pageNumber,
+            data: pageEntry.data,
 
-          // Issue #115
-          if (data.collections) {
-            pageData.collections = data.collections;
-          }
-
-          return {
-            template: page,
+            page: pageEntry.data.page,
             inputPath: this.inputPath,
             fileSlug: this.fileSlugStr,
             filePathStem: this.filePathStem,
-            data: pageData,
-            date: pageData.page.date,
-            pageNumber: pageNumber,
-            outputPath: pageData.page.outputPath,
-            url: pageData.page.url,
-            checkTemplateContent: true,
-            set templateContent(content) {
-              if (content === undefined) {
-                this.checkTemplateContent = false;
-              }
-              this._templateContent = content;
-            },
-            get templateContent() {
-              if (
-                this.checkTemplateContent &&
-                this._templateContent === undefined
-              ) {
-                if (this.template.behavior.isRenderable()) {
-                  throw new TemplateContentPrematureUseError(
-                    `Tried to use templateContent too early (${this.inputPath} page ${this.pageNumber})`
-                  );
-                } else {
-                  throw new TemplateContentUnrenderedTemplateError(
-                    `Tried to use templateContent on unrendered template. You need a valid permalink (or permalink object) to use templateContent on ${this.inputPath} page ${this.pageNumber}`
-                  );
-                }
-              }
-              return this._templateContent;
-            },
+            date: pageEntry.data.page.date,
+            outputPath: pageEntry.data.page.outputPath,
+            url: pageEntry.data.page.url,
           };
+
+          obj = Template.augmentWithTemplateContentProperty(obj);
+
+          return obj;
         })
@@ -820,22 +771,3 @@ );
 
-  // TODO move this into tests (this is only used by tests)
-  async getRenderedTemplates(data) {
-    let pages = await this.getTemplates(data);
-    await Promise.all(
-      pages.map(async (page) => {
-        let content = await page.template.render(page.data);
-
-        page.templateContent = content;
-      })
-    );
-    return pages;
-  }
-
-  async _write(outputPath, finalContent) {
-    let shouldWriteFile = true;
-
-    if (this.isDryRun) {
-      shouldWriteFile = false;
-    }
-
+  async _write({ url, outputPath, data }, finalContent) {
     let lang = {
@@ -846,44 +778,52 @@ start: "Writing",
 
-    if (!shouldWriteFile) {
-      lang = {
-        start: "Skipping",
-        finished: "", // not used, promise doesn’t resolve
-      };
+    if (!this.isDryRun) {
+      let engineList = this.templateRender.getReadableEnginesListDifferingFromFileExtension();
+      this.logger.log(
+        `${lang.start} ${outputPath} from ${this.inputPath}${engineList ? ` (${engineList})` : ""}`
+      );
+    } else if (this.isDryRun) {
+      return;
     }
 
-    let engineList =
-      this.templateRender.getReadableEnginesListDifferingFromFileExtension();
-    this.logger.log(
-      `${lang.start} ${outputPath} from ${this.inputPath}${
-        engineList ? ` (${engineList})` : ""
-      }`
-    );
+    let templateBenchmark = this.bench.get("Template Write");
+    templateBenchmark.before();
 
-    if (!shouldWriteFile) {
-      this.skippedCount++;
-    } else {
-      let templateBenchmark = this.bench.get("Template Write");
-      templateBenchmark.before();
+    // TODO(@zachleat) add a cache to check if this was already created
+    let templateOutputDir = path.parse(outputPath).dir;
+    if (templateOutputDir) {
+      await mkdir(templateOutputDir, { recursive: true });
+    }
 
-      // TODO add a cache to check if this was already created
-      let templateOutputDir = path.parse(outputPath).dir;
-      if (templateOutputDir) {
-        await mkdir(templateOutputDir, { recursive: true });
-      }
+    if (!Buffer.isBuffer(finalContent) && typeof finalContent !== "string") {
+      throw new Error(
+        `The return value from the render function for the ${this.engine.name} template was not a String or Buffer. Received ${finalContent}`
+      );
+    }
 
-      if (!Buffer.isBuffer(finalContent) && typeof finalContent !== "string") {
-        throw new Error(
-          `The return value from the render function for the ${this.engine.name} template was not a String or Buffer. Received ${finalContent}`
-        );
+    return writeFile(outputPath, finalContent).then(() => {
+      templateBenchmark.after();
+      this.writeCount++;
+      debug(`${outputPath} ${lang.finished}.`);
+
+      let ret = {
+        inputPath: this.inputPath,
+        outputPath: outputPath,
+        url,
+        content: finalContent,
+      };
+
+      if (data && this.config.dataFilterSelectors && this.config.dataFilterSelectors.size > 0) {
+        ret.data = this.retrieveDataForJsonOutput(data, this.config.dataFilterSelectors);
       }
 
-      return writeFile(outputPath, finalContent).then(() => {
-        templateBenchmark.after();
-        this.writeCount++;
-        debug(`${outputPath} ${lang.finished}.`);
-      });
-    }
+      return ret;
+    });
   }
 
   async renderPageEntry(mapEntry, page) {
+    // cache with transforms output
+    if (this._cacheFinalContent) {
+      return this._cacheFinalContent;
+    }
+
     let content;
@@ -899,8 +839,7 @@ let layoutKey = mapEntry.data[this.config.keys.layout];
 
-    await this.runLinters(content, page.inputPath, page.outputPath);
-    content = await this.runTransforms(
-      content,
-      page.inputPath,
-      page.outputPath
-    );
+    await this.runLinters(content, page);
+    content = await this.runTransforms(content, page);
+
+    this._cacheFinalContent = content;
+
     return content;
@@ -936,10 +875,4 @@ }
 
-          if (
-            this.config.dataFilterSelectors &&
-            this.config.dataFilterSelectors.size > 0
-          ) {
-            obj.data = this.retrieveDataForJsonOutput(
-              page.data,
-              this.config.dataFilterSelectors
-            );
+          if (this.config.dataFilterSelectors && this.config.dataFilterSelectors.size > 0) {
+            obj.data = this.retrieveDataForJsonOutput(page.data, this.config.dataFilterSelectors);
           }
@@ -977,3 +910,3 @@
         if (content !== undefined) {
-          return this._write(page.outputPath, content);
+          return this._write(page, content);
         }
@@ -984,4 +917,4 @@ })
 
-  // TODO this but better
   clone() {
+    // TODO do we need to even run the constructor here or can we simplify it even more
     let tmpl = new Template(
@@ -996,15 +929,6 @@ this.inputPath,
 
-    // Avoid re-reads, especially for pagination
-    tmpl.setInputContent(this.inputContent);
-
-    tmpl.logger = this.logger;
-
-    for (let transform of this.transforms) {
-      tmpl.addTransform(transform.name, transform.callback);
+    // preserves caches too, e.g. _frontMatterDataCache
+    for (let key in this) {
+      tmpl[key] = this[key];
     }
-    for (let linter of this.linters) {
-      tmpl.addLinter(linter);
-    }
-    tmpl.setIsVerbose(this.isVerbose);
-    tmpl.setDryRun(this.isDryRun);
 
@@ -1018,6 +942,2 @@ return tmpl;
 
-  getSkippedCount() {
-    return this.skippedCount;
-  }
-
   async getInputFileStat() {
@@ -1059,7 +979,3 @@ if (this._stats) {
     if ("date" in data && data.date) {
-      debug(
-        "getMappedDate: using a date in the data for %o of %o",
-        this.inputPath,
-        data.date
-      );
+      debug("getMappedDate: using a date in the data for %o of %o", this.inputPath, data.date);
       if (data.date instanceof Date) {
@@ -1079,3 +995,3 @@ // YAML does its own date parsing
         // return now if this file is not yet available in `git`
-        return Date.now();
+        return new Date();
       }
@@ -1085,2 +1001,11 @@ if (data.date.toLowerCase() === "last modified") {
       }
+      if (data.date.toLowerCase() === "git created") {
+        let d = getDateFromGitFirstAdded(this.inputPath);
+        if (d) {
+          return d;
+        }
+
+        // return now if this file is not yet available in `git`
+        return new Date();
+      }
       if (data.date.toLowerCase() === "created") {
@@ -1093,12 +1018,5 @@ return this._getDateInstance("birthtimeMs");
       if (!date.isValid) {
-        throw new Error(
-          `date front matter value (${data.date}) is invalid for ${this.inputPath}`
-        );
+        throw new Error(`date front matter value (${data.date}) is invalid for ${this.inputPath}`);
       }
-      debug(
-        "getMappedDate: Luxon parsed %o: %o and %o",
-        data.date,
-        date,
-        date.toJSDate()
-      );
+      debug("getMappedDate: Luxon parsed %o: %o and %o", data.date, date, date.toJSDate());
 
@@ -1109,2 +1027,3 @@ return date.toJSDate();
       if (filepathRegex !== null) {
+        // if multiple are found in the path, use the first one for the date
         let dateObj = DateTime.fromISO(filepathRegex[1], {
@@ -1126,17 +1045,6 @@ zone: "utc",
 
-  /* This is the primary render mechanism, called via TemplateMap->populateContentDataInMap */
-  async getTemplateMapContent(pageMapEntry) {
-    pageMapEntry.template.setWrapWithLayouts(false);
-    let content = await pageMapEntry.template.render(pageMapEntry.data);
-    pageMapEntry.template.setWrapWithLayouts(true);
-
-    return content;
-  }
-
-  async getTemplateMapEntries(dataOverride) {
+  // Important reminder: Template data is first generated in TemplateMap
+  async getTemplateMapEntries(data) {
     debugDev("%o getMapped()", this.inputPath);
 
-    // Important reminder: This is where the template data is first generated via TemplateMap
-    let data = dataOverride || (await this.getData());
-
     this.behavior.setRenderViaDataCascade(data);
@@ -1154,25 +1062,4 @@
   }
-
-  async _testCompleteRender() {
-    let entries = await this.getTemplateMapEntries();
-
-    let nestedContent = await Promise.all(
-      entries.map(async (entry) => {
-        entry._pages = await entry.template.getTemplates(entry.data);
-        return Promise.all(
-          entry._pages.map(async (page) => {
-            page.templateContent = await entry.template.getTemplateMapContent(
-              page
-            );
-            return this.renderPageEntry(entry, page);
-          })
-        );
-      })
-    );
-
-    let contents = [].concat(...nestedContent);
-    return contents;
-  }
 }
 
 module.exports = Template;

src/TemplateBehavior.js

@@ -1,2 +0,2 @@
-const isPlainObject = require("./Util/IsPlainObject");
+const { isPlainObject } = require("@11ty/eleventy-utils");
 
@@ -15,5 +15,9 @@ class TemplateBehavior {
 
+  setRenderableOverride(renderableOverride) {
+    this.renderableOverride = renderableOverride;
+  }
+
   // permalink *has* a build key or output is json/ndjson
   isRenderable() {
-    return this.render || this.isRenderForced();
+    return this.renderableOverride ?? (this.render || this.isRenderForced());
   }
@@ -20,0 +24,0 @@

src/TemplateCache.js

@@ -0,1 +1,5 @@
+const { TemplatePath } = require("@11ty/eleventy-utils");
+
+const eventBus = require("./EventBus");
+
 // Note: this is only used for TemplateLayout right now but could be used for more
@@ -7,2 +11,3 @@ // Just be careful because right now the TemplateLayout cache keys are not directly mapped to paths
     this.cache = {};
+    this.cacheByInputPath = {};
   }
@@ -12,10 +17,35 @@
     this.cache = {};
+    this.cacheByInputPath = {};
   }
 
   size() {
-    return Object.keys(this.cache).length;
+    return Object.keys(this.cacheByInputPath).length;
   }
 
-  add(key, template) {
-    this.cache[key] = template;
+  add(layoutTemplate) {
+    let keys = new Set();
+
+    if (typeof layoutTemplate === "string") {
+      throw new Error(
+        "Invalid argument type passed to TemplateCache->add(). Should be a TemplateLayout."
+      );
+    }
+
+    if ("getFullKey" in layoutTemplate) {
+      keys.add(layoutTemplate.getFullKey());
+    }
+
+    if ("getKey" in layoutTemplate) {
+      // if `key` was an alias, also set to the pathed layout value too
+      // e.g. `layout: "default"` and `layout: "default.liquid"` will both map to the same template.
+      keys.add(layoutTemplate.getKey());
+    }
+
+    for (let key of keys) {
+      this.cache[key] = layoutTemplate;
+    }
+
+    // also the full template input path for use with eleventy --serve/--watch e.g. `_includes/default.liquid` (see `remove` below)
+    let fullPath = TemplatePath.stripLeadingDotSlash(layoutTemplate.inputPath);
+    this.cacheByInputPath[fullPath] = layoutTemplate;
   }
@@ -35,10 +65,28 @@
 
-  remove(key) {
-    if (this.cache[key]) {
+  remove(filePath) {
+    filePath = TemplatePath.stripLeadingDotSlash(filePath);
+
+    if (!this.cacheByInputPath[filePath]) {
+      return;
+    }
+
+    let layoutTemplate = this.cacheByInputPath[filePath];
+    layoutTemplate.resetCaches();
+
+    let keys = layoutTemplate.getCacheKeys();
+    for (let key of keys) {
       delete this.cache[key];
     }
+
+    delete this.cacheByInputPath[filePath];
   }
 }
 
+let layoutCache = new TemplateCache();
+
+eventBus.on("eleventy.resourceModified", (path) => {
+  layoutCache.remove(path);
+});
+
 // singleton
-module.exports = new TemplateCache();
+module.exports = layoutCache;

src/TemplateCollection.js

@@ -12,10 +12,2 @@ const multimatch = require("multimatch");
 
-  // TODO move this into tests (this is only used by tests)
-  async _testAddTemplate(template) {
-    let data = await template.getData();
-    for (let map of await template.getTemplates(data)) {
-      this.add(map);
-    }
-  }
-
   getAll() {
@@ -22,0 +14,0 @@ return this.items.slice();

src/TemplateConfig.js

 const fs = require("fs");
 const chalk = require("kleur");
-const lodashUniq = require("lodash/uniq");
-const lodashMerge = require("lodash/merge");
 const { TemplatePath } = require("@11ty/eleventy-utils");
-const EleventyBaseError = require("./EleventyBaseError");
-const UserConfig = require("./UserConfig");
+
+const EleventyBaseError = require("./EleventyBaseError.js");
+const UserConfig = require("./UserConfig.js");
+const GlobalDependencyMap = require("./GlobalDependencyMap.js");
+
+const { EleventyRequire } = require("./Util/Require.js");
+const merge = require("./Util/Merge.js");
+const unique = require("./Util/Unique");
+const eventBus = require("./EventBus.js");
+
 const debug = require("debug")("Eleventy:TemplateConfig");
 const debugDev = require("debug")("Dev:Eleventy:TemplateConfig");
-const deleteRequireCache = require("./Util/DeleteRequireCache");
 
@@ -55,3 +60,12 @@ /**
      */
-    this.projectConfigPath = projectConfigPath || ".eleventy.js";
+    if (projectConfigPath !== undefined) {
+      if (!projectConfigPath) {
+        // falsy skips config files
+        this.projectConfigPaths = [];
+      } else {
+        this.projectConfigPaths = [projectConfigPath];
+      }
+    } else {
+      this.projectConfigPaths = [".eleventy.js", "eleventy.config.js", "eleventy.config.cjs"];
+    }
 
@@ -84,5 +98,17 @@ if (customRootConfig) {
   getLocalProjectConfigFile() {
-    return TemplatePath.addLeadingDotSlash(this.projectConfigPath);
+    let configFiles = this.getLocalProjectConfigFiles();
+    // Add the configFiles[0] in case of a test, where no file exists on the file system
+    let configFile = configFiles.find((path) => path && fs.existsSync(path)) || configFiles[0];
+    if (configFile) {
+      return configFile;
+    }
   }
 
+  getLocalProjectConfigFiles() {
+    if (this.projectConfigPaths && this.projectConfigPaths.length > 0) {
+      return TemplatePath.addLeadingDotSlashArray(this.projectConfigPaths.filter((path) => path));
+    }
+    return [];
+  }
+
   get inputDir() {
@@ -103,4 +129,7 @@ return this._inputDir;
     this.initializeRootConfig();
+    this.forceReloadConfig();
+    this.usesGraph.reset();
 
-    this.config = this.mergeConfig();
+    // Clear the compile cache
+    eventBus.emit("eleventy.compileCacheReset");
   }
@@ -118,2 +147,10 @@
   /**
+   * Force a reload of the configuration object.
+   */
+  forceReloadConfig() {
+    this.hasConfigMerged = false;
+    this.getConfig();
+  }
+
+  /**
    * Returns the config object.
@@ -138,11 +175,12 @@ *
   setProjectConfigPath(path) {
-    this.projectConfigPath = path;
+    if (path !== undefined) {
+      this.projectConfigPaths = [path];
+    } else {
+      this.projectConfigPaths = [];
+    }
 
     if (this.hasConfigMerged) {
       // merge it again
-      debugDev(
-        "Merging in getConfig again after setting the local project config path."
-      );
-      this.hasConfigMerged = false;
-      this.getConfig();
+      debugDev("Merging in getConfig again after setting the local project config path.");
+      this.forceReloadConfig();
     }
@@ -157,9 +195,23 @@ }
   setPathPrefix(pathPrefix) {
-    debug("Setting pathPrefix to %o", pathPrefix);
-    this.overrides.pathPrefix = pathPrefix;
+    if (pathPrefix && pathPrefix !== "/") {
+      debug("Setting pathPrefix to %o", pathPrefix);
+      this.overrides.pathPrefix = pathPrefix;
+    }
+  }
 
+  /**
+   * Gets the current path prefix denoting the root folder the output will be deployed to
+   *
+   *  @returns {String} - The path prefix string
+   */
+  getPathPrefix() {
+    if (this.overrides.pathPrefix) {
+      return this.overrides.pathPrefix;
+    }
+
     if (!this.hasConfigMerged) {
       this.getConfig();
     }
-    this.config.pathPrefix = pathPrefix;
+
+    return this.config.pathPrefix;
   }
@@ -180,2 +232,11 @@
   /*
+   * Add additional overrides to the root config object, used for testing
+   *
+   * @param {Object} - a subset of the return Object from the user’s config file.
+   */
+  appendToRootConfig(obj) {
+    Object.assign(this.rootConfig, obj);
+  }
+
+  /*
    * Process the userland plugins from the Config
@@ -185,4 +246,5 @@ *
    */
-  processPlugins({ dir }) {
+  processPlugins({ dir, pathPrefix }) {
     this.userConfig.dir = dir;
+    this.userConfig.pathPrefix = pathPrefix;
 
@@ -203,5 +265,3 @@ if (this.logger) {
         let name = this.userConfig._getPluginName(plugin);
-        let namespaces = [storedActiveNamespace, pluginNamespace].filter(
-          (entry) => !!entry
-        );
+        let namespaces = [storedActiveNamespace, pluginNamespace].filter((entry) => !!entry);
 
@@ -214,5 +274,3 @@ let namespaceStr = "";
         throw new EleventyPluginError(
-          `Error processing ${
-            name ? `the \`${name}\`` : "a"
-          } plugin${namespaceStr}`,
+          `Error processing ${name ? `the \`${name}\`` : "a"} plugin${namespaceStr}`,
           e
@@ -227,19 +285,15 @@ );
   /**
-   * Merges different config files together.
+   * Fetches and executes the local configuration file
    *
-   * @param {String} projectConfigPath - Path to project config.
-   * @returns {{}} merged - The merged config file.
+   * @returns {{}} merged - The merged config file object.
    */
-  mergeConfig() {
+  requireLocalConfigFile() {
     let localConfig = {};
-    let path = TemplatePath.absolutePath(this.projectConfigPath);
+    let path = this.projectConfigPaths.filter((path) => path).find((path) => fs.existsSync(path));
 
     debug(`Merging config with ${path}`);
 
-    if (fs.existsSync(path)) {
+    if (path) {
       try {
-        // remove from require cache so it will grab a fresh copy
-        deleteRequireCache(path);
-
-        localConfig = require(path);
+        localConfig = EleventyRequire(path);
         // debug( "localConfig require return value: %o", localConfig );
@@ -250,6 +304,3 @@ if (typeof localConfig === "function") {
 
-          if (
-            typeof localConfig === "object" &&
-            typeof localConfig.then === "function"
-          ) {
+          if (typeof localConfig === "object" && typeof localConfig.then === "function") {
             throw new EleventyConfigError(
@@ -285,47 +336,99 @@ `Error in your Eleventy config file '${path}': Returning a promise is not yet supported.`
 
+    return localConfig;
+  }
+
+  /**
+   * Merges different config files together.
+   *
+   * @param {String} projectConfigPath - Path to project config.
+   * @returns {{}} merged - The merged config file.
+   */
+  mergeConfig() {
+    let localConfig = this.requireLocalConfigFile();
+
+    // Template Formats:
+    // 1. Root Config (usually defaultConfig.js)
+    // 2. Local Config return object (project .eleventy.js)
+    // 3.
+    let templateFormats = this.rootConfig.templateFormats || [];
+    if (localConfig && localConfig.templateFormats) {
+      templateFormats = localConfig.templateFormats;
+      delete localConfig.templateFormats;
+    }
+
+    let mergedConfig = merge({}, this.rootConfig, localConfig);
+
+    // Setup a few properties for plugins:
+
+    // Setup pathPrefix set via command line for plugin consumption
+    if (this.overrides.pathPrefix) {
+      mergedConfig.pathPrefix = this.overrides.pathPrefix;
+    }
+
+    // Returning a falsy value (e.g. "") from user config should reset to the default value.
+    if (!mergedConfig.pathPrefix) {
+      mergedConfig.pathPrefix = this.rootConfig.pathPrefix;
+    }
+
     // Delay processing plugins until after the result of localConfig is returned
     // But BEFORE the rest of the config options are merged
     // this way we can pass directories and other template information to plugins
-    this.processPlugins(localConfig || {});
 
-    let eleventyConfigApiMergingObject =
-      this.userConfig.getMergingConfigObject();
+    // Temporarily restore templateFormats
+    mergedConfig.templateFormats = templateFormats;
 
-    // remove special merge keys from object
+    this.processPlugins(mergedConfig);
 
-    let savedForSpecialMerge = {
-      templateFormatsAdded: eleventyConfigApiMergingObject.templateFormatsAdded,
-    };
+    delete mergedConfig.templateFormats;
+
+    let eleventyConfigApiMergingObject = this.userConfig.getMergingConfigObject();
+
+    // `templateFormats` is an override via `setTemplateFormats`
+    // `templateFormatsAdded` is additive via `addTemplateFormats`
+    if (eleventyConfigApiMergingObject && eleventyConfigApiMergingObject.templateFormats) {
+      templateFormats = eleventyConfigApiMergingObject.templateFormats;
+      delete eleventyConfigApiMergingObject.templateFormats;
+    }
+
+    let templateFormatsAdded = eleventyConfigApiMergingObject.templateFormatsAdded || [];
     delete eleventyConfigApiMergingObject.templateFormatsAdded;
 
-    localConfig = lodashMerge(localConfig, eleventyConfigApiMergingObject);
+    templateFormats = unique([...templateFormats, ...templateFormatsAdded]);
 
-    // blow away any templateFormats set in config return object and prefer those set in config API.
-    localConfig.templateFormats =
-      eleventyConfigApiMergingObject.templateFormats ||
-      localConfig.templateFormats;
+    merge(mergedConfig, eleventyConfigApiMergingObject);
 
-    // debug("this.userConfig.getMergingConfigObject: %o", this.userConfig.getMergingConfigObject());
-    debug("localConfig: %o", localConfig);
+    // Apply overrides, currently only pathPrefix uses this I think!
     debug("overrides: %o", this.overrides);
+    merge(mergedConfig, this.overrides);
 
-    // Object assign overrides original values (good only for templateFormats) but not good for anything else
-    let merged = lodashMerge({}, this.rootConfig, localConfig, this.overrides);
-    // blow away any templateFormats upstream (don’t deep merge)
-    merged.templateFormats =
-      localConfig.templateFormats || this.rootConfig.templateFormats;
+    // Restore templateFormats
+    mergedConfig.templateFormats = templateFormats;
 
-    // Additive should preserve original templateFormats, wherever those come from (config API or config return object)
-    if (savedForSpecialMerge.templateFormatsAdded) {
-      merged.templateFormats = merged.templateFormats.concat(
-        savedForSpecialMerge.templateFormatsAdded
-      );
+    debug("Current configuration: %o", mergedConfig);
+
+    this.afterConfigMergeActions(mergedConfig);
+
+    return mergedConfig;
+  }
+
+  get usesGraph() {
+    if (!this._usesGraph) {
+      this._usesGraph = new GlobalDependencyMap();
     }
+    return this._usesGraph;
+  }
 
-    // Unique
-    merged.templateFormats = lodashUniq(merged.templateFormats);
+  afterConfigMergeActions(eleventyConfig) {
+    // Add to the merged config too
+    eleventyConfig.uses = this.usesGraph;
 
-    debug("Current configuration: %o", merged);
+    // this is used for the layouts event
+    this.usesGraph.setConfig(eleventyConfig);
+  }
 
-    return merged;
+  get uses() {
+    if (!this.usesGraph) {
+      throw new Error("The Eleventy Global Dependency Graph has not yet been initialized.");
+    }
+    return this.usesGraph;
   }
@@ -332,0 +435,0 @@ }

src/TemplateContent.js

@@ -7,3 +7,3 @@ const os = require("os");
 const matter = require("gray-matter");
-const lodashSet = require("lodash/set");
+const lodashSet = require("lodash.set");
 const { TemplatePath } = require("@11ty/eleventy-utils");
@@ -29,5 +29,3 @@
     if (!config) {
-      throw new TemplateContentConfigError(
-        "Missing `config` argument to TemplateContent"
-      );
+      throw new TemplateContentConfigError("Missing `config` argument to TemplateContent");
     }
@@ -45,2 +43,33 @@ this.config = config;
 
+  getResetTypes(types) {
+    if (types) {
+      return Object.assign(
+        {
+          data: false,
+          read: false,
+          render: false,
+        },
+        types
+      );
+    }
+
+    return {
+      data: true,
+      read: true,
+      render: true,
+    };
+  }
+
+  // Called during an incremental build when the template instance is cached but needs to be reset because it has changed
+  resetCaches(types) {
+    types = this.getResetTypes(types);
+
+    if (types.read) {
+      delete this.readingPromise;
+      delete this.inputContent;
+      delete this.frontMatter;
+      delete this._frontMatterDataCache;
+    }
+  }
+
   /* Used by tests */
@@ -77,5 +106,3 @@ get extensionMap() {
     }
-    throw new TemplateContentConfigError(
-      "Tried to get an eleventyConfig but none was found."
-    );
+    throw new TemplateContentConfigError("Tried to get an eleventyConfig but none was found.");
   }
@@ -89,7 +116,3 @@
     if (!this._templateRender) {
-      this._templateRender = new TemplateRender(
-        this.inputPath,
-        this.inputDir,
-        this.config
-      );
+      this._templateRender = new TemplateRender(this.inputPath, this.inputDir, this.config);
       this._templateRender.extensionMap = this.extensionMap;
@@ -101,2 +124,20 @@ }
 
+  // For monkey patchers
+  get frontMatter() {
+    if (this.frontMatterOverride) {
+      return this.frontMatterOverride;
+    } else if (this._frontMatter) {
+      return this._frontMatter;
+    } else {
+      throw new Error(
+        "Unfortunately you’re using code that monkey patched some Eleventy internals and it isn’t async-friendly."
+      );
+    }
+  }
+
+  // For monkey patchers
+  set frontMatter(contentOverride) {
+    this.frontMatterOverride = contentOverride;
+  }
+
   getInputPath() {
@@ -111,44 +152,65 @@ return this.inputPath;
   async read() {
-    if (this.inputContent) {
-      await this.inputContent;
-    } else {
-      this.inputContent = await this.getInputContent();
-    }
+    if (!this.readingPromise) {
+      if (!this.inputContent) {
+        // cache the promise
+        this.inputContent = this.getInputContent();
+      }
 
-    if (this.inputContent) {
-      let options = this.config.frontMatterParsingOptions || {};
-      let fm;
-      try {
-        fm = matter(this.inputContent, options);
-      } catch (e) {
-        throw new TemplateContentFrontMatterError(
-          `Having trouble reading front matter from template ${this.inputPath}`,
-          e
-        );
-      }
-      if (options.excerpt && fm.excerpt) {
-        let excerptString = fm.excerpt + (options.excerpt_separator || "---");
-        if (fm.content.startsWith(excerptString + os.EOL)) {
-          // with a newline after excerpt separator
-          fm.content =
-            fm.excerpt.trim() +
-            "\n" +
-            fm.content.substr((excerptString + os.EOL).length);
-        } else if (fm.content.startsWith(excerptString)) {
-          // no newline after excerpt separator
-          fm.content = fm.excerpt + fm.content.substr(excerptString.length);
+      this.readingPromise = new Promise(async (resolve, reject) => {
+        try {
+          let content = await this.inputContent;
+
+          if (content) {
+            let options = this.config.frontMatterParsingOptions || {};
+            let fm;
+            try {
+              fm = matter(content, options);
+            } catch (e) {
+              throw new TemplateContentFrontMatterError(
+                `Having trouble reading front matter from template ${this.inputPath}`,
+                e
+              );
+            }
+
+            if (options.excerpt && fm.excerpt) {
+              let excerptString = fm.excerpt + (options.excerpt_separator || "---");
+              if (fm.content.startsWith(excerptString + os.EOL)) {
+                // with an os-specific newline after excerpt separator
+                fm.content =
+                  fm.excerpt.trim() + "\n" + fm.content.slice((excerptString + os.EOL).length);
+              } else if (fm.content.startsWith(excerptString + "\n")) {
+                // with a newline (\n) after excerpt separator
+                // This is necessary for some git configurations on windows
+                fm.content =
+                  fm.excerpt.trim() + "\n" + fm.content.slice((excerptString + 1).length);
+              } else if (fm.content.startsWith(excerptString)) {
+                // no newline after excerpt separator
+                fm.content = fm.excerpt + fm.content.slice(excerptString.length);
+              }
+
+              // alias, defaults to page.excerpt
+              let alias = options.excerpt_alias || "page.excerpt";
+              lodashSet(fm.data, alias, fm.excerpt);
+            }
+
+            // For monkey patchers that used `frontMatter` 🤧
+            // https://github.com/11ty/eleventy/issues/613#issuecomment-999637109
+            // https://github.com/11ty/eleventy/issues/2710#issuecomment-1373854834
+            this._frontMatter = fm;
+
+            resolve(fm);
+          } else {
+            resolve({
+              data: {},
+              content: "",
+              excerpt: "",
+            });
+          }
+        } catch (e) {
+          reject(e);
         }
+      });
+    }
 
-        // alias, defaults to page.excerpt
-        let alias = options.excerpt_alias || "page.excerpt";
-        lodashSet(fm.data, alias, fm.excerpt);
-      }
-      this.frontMatter = fm;
-    } else {
-      this.frontMatter = {
-        data: {},
-        content: "",
-        excerpt: "",
-      };
-    }
+    return this.readingPromise;
   }
@@ -164,3 +226,3 @@
 
-  static deleteCached(path) {
+  static deleteFromInputCache(path) {
     this._inputCache.delete(TemplatePath.absolutePath(path));
@@ -178,8 +240,12 @@ }
     }
+
     let templateBenchmark = this.bench.get("Template Read");
     templateBenchmark.before();
+
     let content;
+
     if (this.config.useTemplateCache) {
       content = TemplateContent.getCached(this.inputPath);
     }
+
     if (!content) {
@@ -192,2 +258,3 @@ content = await readFile(this.inputPath, "utf8");
     }
+
     templateBenchmark.after();
@@ -198,31 +265,32 @@
 
+  // This might only be used in tests
   async getFrontMatter() {
-    if (!this.frontMatter) {
-      await this.read();
-    }
-
-    return this.frontMatter;
+    let fm = this.frontMatterOverride ? this.frontMatterOverride : await this.read();
+    return fm;
   }
 
   async getPreRender() {
-    if (!this.frontMatter) {
-      await this.read();
-    }
+    let fm = this.frontMatterOverride ? this.frontMatterOverride : await this.read();
 
-    return this.frontMatter.content;
+    return fm.content;
   }
 
   async getFrontMatterData() {
-    if (this._frontMatterDataCache) {
-      return this._frontMatterDataCache;
+    if (!this._frontMatterDataCache) {
+      this._frontMatterDataCache = new Promise(async (resolve, reject) => {
+        try {
+          let fm = await this.read();
+
+          let extraData = await this.engine.getExtraDataFromFile(this.inputPath);
+          let data = TemplateData.mergeDeep({}, fm.data, extraData);
+
+          let cleanedData = TemplateData.cleanupData(data);
+          resolve(cleanedData);
+        } catch (e) {
+          reject(e);
+        }
+      });
     }
 
-    if (!this.frontMatter) {
-      await this.read();
-    }
-    let extraData = await this.engine.getExtraDataFromFile(this.inputPath);
-    let data = TemplateData.mergeDeep({}, this.frontMatter.data, extraData);
-    let cleanedData = TemplateData.cleanupData(data);
-    this._frontMatterDataCache = cleanedData;
-    return cleanedData;
+    return this._frontMatterDataCache;
   }
@@ -235,10 +303,5 @@
 
-  async setupTemplateRender(bypassMarkdown) {
-    let engineOverride = await this.getEngineOverride();
+  async setupTemplateRender(engineOverride, bypassMarkdown) {
     if (engineOverride !== undefined) {
-      debugDev(
-        "%o overriding template engine to use %o",
-        this.inputPath,
-        engineOverride
-      );
+      debugDev("%o overriding template engine to use %o", this.inputPath, engineOverride);
 
@@ -251,18 +314,17 @@ this.templateRender.setEngineOverride(engineOverride, bypassMarkdown);
 
-  _getCompileCache(str, bypassMarkdown) {
-    let engineName = this.engine.getName() + "::" + !!bypassMarkdown;
-    let engineMap = TemplateContent._compileEngineCache.get(engineName);
-    if (!engineMap) {
-      engineMap = new Map();
-      TemplateContent._compileEngineCache.set(engineName, engineMap);
+  _getCompileCache(str) {
+    // Caches used to be bifurcated based on engine name, now they’re based on inputPath
+    let inputPathMap = TemplateContent._compileCache.get(this.inputPath);
+    if (!inputPathMap) {
+      inputPathMap = new Map();
+      TemplateContent._compileCache.set(this.inputPath, inputPathMap);
     }
 
     let cacheable = this.engine.cacheable;
-    let key = this.engine.getCompileCacheKey(str, this.inputPath);
-
-    return [cacheable, key, engineMap];
+    let { useCache, key } = this.engine.getCompileCacheKey(str, this.inputPath);
+    return [cacheable, key, inputPathMap, useCache];
   }
 
-  async compile(str, bypassMarkdown) {
-    await this.setupTemplateRender(bypassMarkdown);
+  async compile(str, bypassMarkdown, engineOverride) {
+    await this.setupTemplateRender(engineOverride, bypassMarkdown);
 
@@ -275,7 +337,3 @@ if (bypassMarkdown && !this.engine.needsCompilation(str)) {
 
-    debugDev(
-      "%o compile() using engine: %o",
-      this.inputPath,
-      this.templateRender.engineName
-    );
+    debugDev("%o compile() using engine: %o", this.inputPath, this.templateRender.engineName);
 
@@ -285,12 +343,13 @@ try {
       if (this.config.useTemplateCache) {
-        let [cacheable, key, cache] = this._getCompileCache(
-          str,
-          bypassMarkdown
-        );
+        let [cacheable, key, cache, useCache] = this._getCompileCache(str);
         if (cacheable && key) {
-          if (cache.has(key)) {
-            this.bench.get("Template Compile Cache Hit").incrementCount();
+          if (useCache && cache.has(key)) {
+            this.bench.get("(count) Template Compile Cache Hit").incrementCount();
             return cache.get(key);
           }
 
+          this.bench.get("(count) Template Compile Cache Miss").incrementCount();
+
+          // Compile cache is cleared when the resource is modified (below)
+
           // Compilation is async, so we eagerly cache a Promise that eventually
@@ -320,3 +379,3 @@ // resolves to the compiled function
     } catch (e) {
-      let [cacheable, key, cache] = this._getCompileCache(str, bypassMarkdown);
+      let [cacheable, key, cache] = this._getCompileCache(str);
       if (cacheable && key) {
@@ -334,5 +393,16 @@ cache.delete(key);
   getParseForSymbolsFunction(str) {
-    if ("parseForSymbols" in this.engine) {
+    let engine = this.engine;
+
+    // Don’t use markdown as the engine to parse for symbols
+    let preprocessorEngine = this.templateRender.getPreprocessorEngine(); // TODO pass in engineOverride here
+    if (preprocessorEngine && engine.getName() !== preprocessorEngine) {
+      let replacementEngine = this.templateRender.getEngineByName(preprocessorEngine);
+      if (replacementEngine) {
+        engine = replacementEngine;
+      }
+    }
+
+    if ("parseForSymbols" in engine) {
       return () => {
-        return this.engine.parseForSymbols(str);
+        return engine.parseForSymbols(str);
       };
@@ -364,3 +434,9 @@ }
   async renderPermalink(permalink, data) {
+    this.bench.get("(count) Render Permalink").incrementCount();
+    this.bench
+      .get(`(count) > Render Permalink > ${this.inputPath}${this._getPaginationLogSuffix(data)}`)
+      .incrementCount();
+
     let permalinkCompilation = this.engine.permalinkNeedsCompilation(permalink);
+
     // No string compilation:
@@ -376,3 +452,3 @@ //    ({ compileOptions: { permalink: "raw" }})
 
-    /* Usage:
+    /* Custom `compile` function for permalinks, usage:
     permalink: function(permalinkString, inputPath) {
@@ -385,9 +461,6 @@ return async function(data) {
     if (permalinkCompilation && typeof permalinkCompilation === "function") {
-      permalink = await this._renderFunction(
-        permalinkCompilation,
-        permalink,
-        this.inputPath
-      );
+      permalink = await this._renderFunction(permalinkCompilation, permalink, this.inputPath);
     }
 
+    // Raw permalink function (in the app code data cascade)
     if (typeof permalink === "function") {
@@ -404,2 +477,18 @@ return this._renderFunction(permalink, data);
 
+  _getPaginationLogSuffix(data) {
+    let suffix = [];
+    if ("pagination" in data) {
+      suffix.push(" (");
+      if (data.pagination.pages) {
+        suffix.push(
+          `${data.pagination.pages.length} page${data.pagination.pages.length !== 1 ? "s" : ""}`
+        );
+      } else {
+        suffix.push("Pagination");
+      }
+      suffix.push(")");
+    }
+    return suffix.join("");
+  }
+
   async _render(str, data, bypassMarkdown) {
@@ -411,9 +500,8 @@ try {
 
-      let fn = await this.compile(str, bypassMarkdown);
+      let fn = await this.compile(str, bypassMarkdown, data[this.config.keys.engineOverride]);
+
       if (fn === undefined) {
         return;
       } else if (typeof fn !== "function") {
-        throw new Error(
-          `The \`compile\` function did not return a function. Received ${fn}`
-        );
+        throw new Error(`The \`compile\` function did not return a function. Received ${fn}`);
       }
@@ -423,23 +511,10 @@
       let templateBenchmark = this.bench.get("Render");
-      let paginationSuffix = [];
-      if ("pagination" in data) {
-        paginationSuffix.push(" (Pagination");
-        if (data.pagination.pages) {
-          paginationSuffix.push(
-            `: ${data.pagination.pages.length} page${
-              data.pagination.pages.length !== 1 ? "s" : ""
-            }`
-          );
-        }
-        paginationSuffix.push(")");
-      }
-
+      // Skip benchmark for each individual pagination entry (very busy output)
+      let logRenderToOutputBenchmark = "pagination" in data;
       let inputPathBenchmark = this.bench.get(
-        `> Render > ${this.inputPath}${paginationSuffix.join("")}`
+        `> Render > ${this.inputPath}${this._getPaginationLogSuffix(data)}`
       );
       let outputPathBenchmark;
-      if (data.page && data.page.outputPath) {
-        outputPathBenchmark = this.bench.get(
-          `> Render > ${data.page.outputPath}`
-        );
+      if (data.page && data.page.outputPath && logRenderToOutputBenchmark) {
+        outputPathBenchmark = this.bench.get(`> Render to > ${data.page.outputPath}`);
       }
@@ -464,6 +539,3 @@
       templateBenchmark.after();
-      debugDev(
-        "%o getCompiledTemplate called, rendered content created",
-        this.inputPath
-      );
+      debugDev("%o getCompiledTemplate called, rendered content created", this.inputPath);
       return rendered;
@@ -475,6 +547,3 @@ } catch (e) {
         let engine = this.templateRender.getReadableEnginesList();
-        debug(
-          `Having trouble rendering ${engine} template ${this.inputPath}: %O`,
-          str
-        );
+        debug(`Having trouble rendering ${engine} template ${this.inputPath}: %O`, str);
         throw new TemplateContentRenderError(
@@ -489,4 +558,3 @@ `Having trouble rendering ${engine} template ${this.inputPath}`,
   getExtensionEntries() {
-    let extensions = this.templateRender.engine.extensionEntries;
-    return extensions;
+    return this.engine.extensionEntries;
   }
@@ -500,5 +568,14 @@
 
-    let extensionEntries = this.getExtensionEntries().filter(
-      (entry) => !!entry.isIncrementalMatch
+    let hasDependencies = this.engine.hasDependencies(incrementalFile);
+
+    let isRelevant = this.engine.isFileRelevantTo(this.inputPath, incrementalFile);
+
+    debug(
+      "Test dependencies to see if %o is relevant to %o: %o",
+      this.inputPath,
+      incrementalFile,
+      isRelevant
     );
+
+    let extensionEntries = this.getExtensionEntries().filter((entry) => !!entry.isIncrementalMatch);
     if (extensionEntries.length) {
@@ -510,2 +587,5 @@ for (let entry of extensionEntries) {
               inputPath: this.inputPath,
+              isFullTemplate: metadata.isFullTemplate,
+              isFileRelevantToInputPath: isRelevant,
+              doesFileHaveDependencies: hasDependencies,
             },
@@ -521,12 +601,13 @@ incrementalFile
     } else {
+      // Not great way of building all templates if this is a layout, include, JS dependency.
+      // TODO improve this for default template syntaxes
+
       // This is the fallback way of determining if something is incremental (no isIncrementalMatch available)
-
-      // Not great way of building all templates if this is a layout, include, JS dependency.
-      // TODO improve this for default langs
-      if (!metadata.isFullTemplate) {
+      // This will be true if the inputPath and incrementalFile are the same
+      if (isRelevant) {
         return true;
       }
 
-      // only build if this input path is the same as the file that was changed
-      if (this.inputPath === incrementalFile) {
+      // only return true here if dependencies are not known
+      if (!hasDependencies && !metadata.isFullTemplate) {
         return true;
@@ -541,7 +622,20 @@ }
 TemplateContent._inputCache = new Map();
-TemplateContent._compileEngineCache = new Map();
+TemplateContent._compileCache = new Map();
 eventBus.on("eleventy.resourceModified", (path) => {
-  TemplateContent.deleteCached(path);
+  // delete from input cache
+  TemplateContent.deleteFromInputCache(path);
+
+  // delete from compile cache
+  let normalized = TemplatePath.addLeadingDotSlash(path);
+  let compileCache = TemplateContent._compileCache.get(normalized);
+  if (compileCache) {
+    compileCache.clear();
+  }
 });
 
+// Used when the configuration file reset https://github.com/11ty/eleventy/issues/2147
+eventBus.on("eleventy.compileCacheReset", (path) => {
+  TemplateContent._compileCache = new Map();
+});
+
 module.exports = TemplateContent;

src/TemplateData.js

@@ -1,16 +0,14 @@
-const pkg = require("../package.json");
 const fs = require("fs");
-const fastglob = require("fast-glob");
 const path = require("path");
-const lodashset = require("lodash/set");
-const lodashget = require("lodash/get");
-const lodashUniq = require("lodash/uniq");
-const semver = require("semver");
-const { TemplatePath } = require("@11ty/eleventy-utils");
+const lodashset = require("lodash.set");
+const lodashget = require("lodash.get");
+const { TemplatePath, isPlainObject } = require("@11ty/eleventy-utils");
 
 const merge = require("./Util/Merge");
-const TemplateRender = require("./TemplateRender");
+const unique = require("./Util/Unique");
 const TemplateGlob = require("./TemplateGlob");
 const EleventyExtensionMap = require("./EleventyExtensionMap");
 const EleventyBaseError = require("./EleventyBaseError");
+const TemplateDataInitialGlobalData = require("./TemplateDataInitialGlobalData");
+const { EleventyRequire } = require("./Util/Require");
 
@@ -20,3 +18,2 @@ const debugWarn = require("debug")("Eleventy:Warnings");
 const debugDev = require("debug")("Dev:Eleventy:TemplateData");
-const deleteRequireCache = require("./Util/DeleteRequireCache");
 
@@ -58,4 +55,2 @@ class FSExistsCache {
 
-    this.dataTemplateEngine = this.config.dataTemplateEngine;
-
     this.inputDirNeedsCheck = false;
@@ -71,4 +66,10 @@ this.setInputDir(inputDir);
     this._fsExistsCache = new FSExistsCache();
+
+    this.initialGlobalData = new TemplateDataInitialGlobalData(this.eleventyConfig);
   }
 
+  setFileSystemSearch(fileSystemSearch) {
+    this.fileSystemSearch = fileSystemSearch;
+  }
+
   get extensionMap() {
@@ -96,3 +97,2 @@ if (!this._extensionMap) {
     this.config = config;
-    this.dataTemplateEngine = this.config.dataTemplateEngine;
   }
@@ -108,6 +108,2 @@
 
-  setDataTemplateEngine(engineName) {
-    this.dataTemplateEngine = engineName;
-  }
-
   getRawImports() {
@@ -119,6 +115,3 @@ let pkgPath = TemplatePath.absolutePath("package.json");
     } catch (e) {
-      debug(
-        "Could not find and/or require package.json for data preprocessing at %o",
-        pkgPath
-      );
+      debug("Could not find and/or require package.json for data preprocessing at %o", pkgPath);
     }
@@ -135,11 +128,6 @@
     this.globalData = null;
+    this.configApiGlobalData = null;
     this.templateDirectoryData = {};
   }
 
-  async cacheData() {
-    this.clearData();
-
-    return this.getData();
-  }
-
   _getGlobalDataGlobByExtension(dir, extension) {
@@ -177,25 +165,77 @@ return TemplateGlob.normalizePath(
 
+  // This is a backwards compatibility helper with the old `jsDataFileSuffix` configuration API
+  getDataFileSuffixes() {
+    // New API
+    if (Array.isArray(this.config.dataFileSuffixes)) {
+      return this.config.dataFileSuffixes;
+    }
+
+    // Backwards compatibility
+    if (this.config.jsDataFileSuffix) {
+      let suffixes = [];
+      suffixes.push(this.config.jsDataFileSuffix); // e.g. filename.11tydata.json
+      suffixes.push(""); // suffix-less for free with old API, e.g. filename.json
+      return suffixes;
+    }
+    return []; // if both of these entries are set to false, use no files
+  }
+
+  // This is used exclusively for --watch and --serve chokidar targets
   async getTemplateDataFileGlob() {
-    let dir = await this.getInputDir();
-    let paths = [
-      `${dir}/**/*.json`, // covers .11tydata.json too
-      `${dir}/**/*${this.config.jsDataFileSuffix}.cjs`,
-      `${dir}/**/*${this.config.jsDataFileSuffix}.js`,
-    ];
+    let suffixes = this.getDataFileSuffixes();
+    let globSuffixesWithLeadingDot = new Set();
+    globSuffixesWithLeadingDot.add("json"); // covers .11tydata.json too
+    let globSuffixesWithoutLeadingDot = new Set();
 
+    // Typically using [ '.11tydata', '' ] suffixes to find data files
+    for (let suffix of suffixes) {
+      // TODO the `suffix` truthiness check is purely for backwards compat?
+      if (suffix && typeof suffix === "string") {
+        if (suffix.startsWith(".")) {
+          // .suffix.js
+          globSuffixesWithLeadingDot.add(`${suffix.slice(1)}.cjs`);
+          globSuffixesWithLeadingDot.add(`${suffix.slice(1)}.js`);
+        } else {
+          // "suffix.js" without leading dot
+          globSuffixesWithoutLeadingDot.add(`${suffix || ""}.cjs`);
+          globSuffixesWithoutLeadingDot.add(`${suffix || ""}.js`);
+        }
+      }
+    }
+
+    // Configuration Data Extensions e.g. yaml
     if (this.hasUserDataExtensions()) {
-      let userPaths = this.getUserDataExtensions().map(
-        (extension) => `${dir}/**/*.${extension}` // covers .11tydata.{extension} too
-      );
-      paths = userPaths.concat(paths);
+      for (let extension of this.getUserDataExtensions()) {
+        globSuffixesWithLeadingDot.add(extension); // covers .11tydata.{extension} too
+      }
     }
 
+    let dir = await this.getInputDir();
+    let paths = [];
+    if (globSuffixesWithLeadingDot.size > 0) {
+      paths.push(`${dir}/**/*.{${Array.from(globSuffixesWithLeadingDot).join(",")}}`);
+    }
+    if (globSuffixesWithoutLeadingDot.size > 0) {
+      paths.push(`${dir}/**/*{${Array.from(globSuffixesWithoutLeadingDot).join(",")}}`);
+    }
+
     return TemplatePath.addLeadingDotSlashArray(paths);
   }
 
+  // For spidering dependencies
+  // TODO Can we reuse getTemplateDataFileGlob instead? Maybe just filter off the .json files before scanning for dependencies
   async getTemplateJavaScriptDataFileGlob() {
     let dir = await this.getInputDir();
-    return TemplatePath.addLeadingDotSlashArray([
-      `${dir}/**/*${this.config.jsDataFileSuffix}.js`,
-    ]);
+
+    let paths = [];
+    let suffixes = this.getDataFileSuffixes();
+    for (let suffix of suffixes) {
+      if (suffix) {
+        // TODO this check is purely for backwards compat and I kinda feel like it shouldn’t be here
+        // paths.push(`${dir}/**/*${suffix || ""}.cjs`); // Same as above
+        paths.push(`${dir}/**/*${suffix || ""}.js`);
+      }
+    }
+
+    return TemplatePath.addLeadingDotSlashArray(paths);
   }
@@ -206,4 +246,4 @@
 
-    let extGlob = this.getGlobalDataExtensionPriorities().join("|");
-    return [this._getGlobalDataGlobByExtension(dir, "(" + extGlob + ")")];
+    let extGlob = this.getGlobalDataExtensionPriorities().join(",");
+    return [this._getGlobalDataGlobByExtension(dir, "{" + extGlob + "}")];
   }
@@ -232,8 +272,6 @@
 
-    let fsBench = this.benchmarks.aggregate.get("Searching the file system");
+    let fsBench = this.benchmarks.aggregate.get("Searching the file system (data)");
     fsBench.before();
-    let paths = fastglob.sync(await this.getGlobalDataGlob(), {
-      caseSensitiveMatch: false,
-      dot: true,
-    });
+    let globs = await this.getGlobalDataGlob();
+    let paths = await this.fileSystemSearch.search("global-data", globs);
     fsBench.after();
@@ -261,6 +299,3 @@
   getObjectPathForDataFile(dataFilePath) {
-    let reducedPath = TemplatePath.stripLeadingSubPath(
-      dataFilePath,
-      this.dataDir
-    );
+    let reducedPath = TemplatePath.stripLeadingSubPath(dataFilePath, this.dataDir);
     let parsed = path.parse(reducedPath);
@@ -270,3 +305,3 @@ let folders = parsed.dir ? parsed.dir.split("/") : [];
 
-    return folders.join(".");
+    return folders;
   }
@@ -277,5 +312,3 @@
     let globalData = {};
-    let files = TemplatePath.addLeadingDotSlashArray(
-      await this.getGlobalDataFiles()
-    );
+    let files = TemplatePath.addLeadingDotSlashArray(await this.getGlobalDataFiles());
 
@@ -287,10 +320,16 @@ this.config.events.emit("eleventy.globalDataFiles", files);
     for (let j = 0, k = files.length; j < k; j++) {
-      let objectPathTarget = await this.getObjectPathForDataFile(files[j]);
       let data = await this.getDataValue(files[j], rawImports);
+      let objectPathTarget = this.getObjectPathForDataFile(files[j]);
 
+      // Since we're joining directory paths and an array is not useable as an objectkey since two identical arrays are not double equal,
+      // we can just join the array by a forbidden character ("/"" is chosen here, since it works on Linux, Mac and Windows).
+      // If at some point this isn't enough anymore, it would be possible to just use JSON.stringify(objectPathTarget) since that
+      // is guaranteed to work but is signifivcantly slower.
+      let objectPathTargetString = objectPathTarget.join(path.sep);
+
       // if two global files have the same path (but different extensions)
       // and conflict, let’s merge them.
-      if (dataFileConflicts[objectPathTarget]) {
+      if (dataFileConflicts[objectPathTargetString]) {
         debugWarn(
-          `merging global data from ${files[j]} with an already existing global data file (${dataFileConflicts[objectPathTarget]}). Overriding existing keys.`
+          `merging global data from ${files[j]} with an already existing global data file (${dataFileConflicts[objectPathTargetString]}). Overriding existing keys.`
         );
@@ -302,6 +341,4 @@
 
-      dataFileConflicts[objectPathTarget] = files[j];
-      debug(
-        `Found global data file ${files[j]} and adding as: ${objectPathTarget}`
-      );
+      dataFileConflicts[objectPathTargetString] = files[j];
+      debug(`Found global data file ${files[j]} and adding as: ${objectPathTarget}`);
       lodashset(globalData, objectPathTarget, data);
@@ -314,46 +351,33 @@ }
   async getInitialGlobalData() {
-    let globalData = {};
+    if (!this.configApiGlobalData) {
+      this.configApiGlobalData = new Promise(async (resolve) => {
+        let globalData = await this.initialGlobalData.getData();
 
-    // via eleventyConfig.addGlobalData
-    if (this.config.globalData) {
-      let keys = Object.keys(this.config.globalData);
-      for (let key of keys) {
-        let returnValue = this.config.globalData[key];
-
-        if (typeof returnValue === "function") {
-          returnValue = await returnValue();
+        if (this.environmentVariables) {
+          if (!("env" in globalData.eleventy)) {
+            globalData.eleventy.env = {};
+          }
+          Object.assign(globalData.eleventy.env, this.environmentVariables);
         }
 
-        lodashset(globalData, key, returnValue);
-      }
+        resolve(globalData);
+      });
     }
 
-    if (!("eleventy" in globalData)) {
-      globalData.eleventy = {};
-    }
-    // #2293 for meta[name=generator]
-    globalData.eleventy.version = semver.coerce(pkg.version).toString();
-    globalData.eleventy.generator = `Eleventy v${globalData.eleventy.version}`;
-
-    if (this.environmentVariables) {
-      if (!("env" in globalData.eleventy)) {
-        globalData.eleventy.env = {};
-      }
-      Object.assign(globalData.eleventy.env, this.environmentVariables);
-    }
-
-    return globalData;
+    return this.configApiGlobalData;
   }
 
-  async getData() {
+  async getGlobalData() {
     let rawImports = this.getRawImports();
 
     if (!this.globalData) {
-      this.configApiGlobalData = await this.getInitialGlobalData();
+      this.globalData = new Promise(async (resolve) => {
+        let configApiGlobalData = await this.getInitialGlobalData();
 
-      let globalJson = await this.getAllGlobalData();
-      let mergedGlobalData = merge(globalJson, this.configApiGlobalData);
+        let globalJson = await this.getAllGlobalData();
+        let mergedGlobalData = merge(globalJson, configApiGlobalData);
 
-      // OK: Shallow merge when combining rawImports (pkg) with global data files
-      this.globalData = Object.assign({}, mergedGlobalData, rawImports);
+        // OK: Shallow merge when combining rawImports (pkg) with global data files
+        resolve(Object.assign({}, mergedGlobalData, rawImports));
+      });
     }
@@ -382,8 +406,27 @@
 
+    let dataSource = {};
     for (let path of localDataPaths) {
-      // clean up data for template/directory data files only.
       let dataForPath = await this.getDataValue(path, null, true);
-      let cleanedDataForPath = TemplateData.cleanupData(dataForPath);
-      TemplateData.mergeDeep(this.config, localData, cleanedDataForPath);
-      // debug("`combineLocalData` (iterating) for %o: %O", path, localData);
+      if (!isPlainObject(dataForPath)) {
+        debug(
+          "Warning: Template and Directory data files expect an object to be returned, instead `%o` returned `%o`",
+          path,
+          dataForPath
+        );
+      } else {
+        // clean up data for template/directory data files only.
+        let cleanedDataForPath = TemplateData.cleanupData(dataForPath);
+        for (let key in cleanedDataForPath) {
+          if (dataSource.hasOwnProperty(key)) {
+            debugWarn(
+              "Local data files have conflicting data. Overwriting '%s' with data from '%s'. Previous data location was from '%s'",
+              key,
+              path,
+              dataSource[key]
+            );
+          }
+          dataSource[key] = path;
+        }
+        TemplateData.mergeDeep(this.config, localData, cleanedDataForPath);
+      }
     }
@@ -398,6 +441,3 @@ return localData;
 
-      this.templateDirectoryData[templatePath] = Object.assign(
-        {},
-        importedData
-      );
+      this.templateDirectoryData[templatePath] = Object.assign({}, importedData);
     }
@@ -407,6 +447,2 @@ return this.templateDirectoryData[templatePath];
 
-  async getGlobalData() {
-    return this.getData();
-  }
-
   getUserDataExtensions() {
@@ -427,5 +463,3 @@ if (!this.config.dataExtensions) {
   isUserDataExtension(extension) {
-    return (
-      this.config.dataExtensions && this.config.dataExtensions.has(extension)
-    );
+    return this.config.dataExtensions && this.config.dataExtensions.has(extension);
   }
@@ -437,45 +471,45 @@
 
-  async _loadFileContents(path) {
+  async _loadFileContents(path, options = {}) {
     let rawInput;
+    let encoding = "utf8";
+    if ("encoding" in options) {
+      encoding = options.encoding;
+    }
+
     try {
-      rawInput = await fs.promises.readFile(path, "utf8");
+      rawInput = await fs.promises.readFile(path, encoding);
     } catch (e) {
       // if file does not exist, return nothing
     }
+
+    // Can return a buffer, string, etc
+    if (typeof rawInput === "string") {
+      return rawInput.trim();
+    }
+
     return rawInput;
   }
 
-  async _parseDataFile(path, rawImports, ignoreProcessing, parser) {
-    let rawInput = await this._loadFileContents(path);
-    let engineName = this.dataTemplateEngine;
+  async _parseDataFile(path, rawImports, ignoreProcessing, parser, options = {}) {
+    let readFile = !("read" in options) || options.read === true;
+    let rawInput;
 
-    if (!rawInput) {
+    if (readFile) {
+      rawInput = await this._loadFileContents(path, options);
+    }
+
+    if (readFile && !rawInput) {
       return {};
     }
 
-    if (ignoreProcessing || engineName === false) {
-      try {
-        return parser(rawInput);
-      } catch (e) {
-        throw new TemplateDataParseError(
-          `Having trouble parsing data file ${path}`,
-          e
-        );
+    try {
+      if (readFile) {
+        return parser(rawInput, path);
+      } else {
+        // path as a first argument is when `read: false`
+        // path as a second argument is for consistency with `read: true` API
+        return parser(path, path);
       }
-    } else {
-      let tr = new TemplateRender(engineName, this.inputDir, this.config);
-      tr.extensionMap = this.extensionMap;
-
-      let fn = await tr.getCompiledTemplate(rawInput);
-
-      try {
-        // pass in rawImports, don’t pass in global data, that’s what we’re parsing
-        let raw = await fn(rawImports);
-        return parser(raw);
-      } catch (e) {
-        throw new TemplateDataParseError(
-          `Having trouble parsing data file ${path}`,
-          e
-        );
-      }
+    } catch (e) {
+      throw new TemplateDataParseError(`Having trouble parsing data file ${path}`, e);
     }
@@ -489,7 +523,3 @@ }
 
-    if (
-      extension === "js" ||
-      extension === "cjs" ||
-      (extension === "json" && (ignoreProcessing || !this.dataTemplateEngine))
-    ) {
+    if (extension === "js" || extension === "cjs") {
       // JS data file or require’d JSON (no preprocessing needed)
@@ -509,5 +539,4 @@ let localPath = TemplatePath.absolutePath(path);
       dataBench.before();
-      deleteRequireCache(localPath);
 
-      let returnValue = require(localPath);
+      let returnValue = EleventyRequire(localPath);
       // TODO special exception for Global data `permalink.js`
@@ -517,3 +546,4 @@ // module.exports = (data) => `${data.page.filePathStem}/`; // Does not work
       if (typeof returnValue === "function") {
-        returnValue = await returnValue(this.configApiGlobalData || {});
+        let configApiGlobalData = await this.getInitialGlobalData();
+        returnValue = await returnValue(configApiGlobalData || {});
       }
@@ -526,12 +556,9 @@
       // Other extensions
-      var parser = this.getUserDataParser(extension);
-      return this._parseDataFile(path, rawImports, ignoreProcessing, parser);
+      let { parser, options } = this.getUserDataParser(extension);
+
+      return this._parseDataFile(path, rawImports, ignoreProcessing, parser, options);
     } else if (extension === "json") {
       // File to string, parse with JSON (preprocess)
-      return this._parseDataFile(
-        path,
-        rawImports,
-        ignoreProcessing,
-        JSON.parse
-      );
+      const parser = (content) => JSON.parse(content);
+      return this._parseDataFile(path, rawImports, ignoreProcessing, parser);
     } else {
@@ -550,16 +577,22 @@ throw new TemplateDataParseError(
 
-  _addBaseToPaths(paths, base, extensions) {
-    let dataSuffix = this.config.jsDataFileSuffix;
+  _addBaseToPaths(paths, base, extensions, nonEmptySuffixesOnly = false) {
+    let suffixes = this.getDataFileSuffixes();
 
-    // data suffix
-    paths.push(base + dataSuffix + ".js");
-    paths.push(base + dataSuffix + ".cjs");
-    paths.push(base + dataSuffix + ".json");
+    for (let suffix of suffixes) {
+      suffix = suffix || "";
 
-    // inject user extensions
-    this._pushExtensionsToPaths(paths, base + dataSuffix, extensions);
+      if (nonEmptySuffixesOnly && suffix === "") {
+        continue;
+      }
 
-    // top level
-    paths.push(base + ".json");
-    this._pushExtensionsToPaths(paths, base, extensions);
+      // data suffix
+      if (suffix) {
+        paths.push(base + suffix + ".js");
+        paths.push(base + suffix + ".cjs");
+      }
+      paths.push(base + suffix + ".json"); // default: .11tydata.json
+
+      // inject user extensions
+      this._pushExtensionsToPaths(paths, base + suffix, extensions);
+    }
   }
@@ -570,5 +603,3 @@
     let parsed = path.parse(templatePath);
-    let inputDir = TemplatePath.addLeadingDotSlash(
-      TemplatePath.normalize(this.inputDir)
-    );
+    let inputDir = TemplatePath.addLeadingDotSlash(TemplatePath.normalize(this.inputDir));
 
@@ -581,12 +612,12 @@ debugDev("getLocalDataPaths(%o)", templatePath);
     if (parsed.dir) {
-      let fileNameNoExt = this.extensionMap.removeTemplateExtension(
-        parsed.base
-      );
+      let fileNameNoExt = this.extensionMap.removeTemplateExtension(parsed.base);
 
+      // default dataSuffix: .11tydata, is appended in _addBaseToPaths
+      debug("Using %o suffixes to find data files.", this.getDataFileSuffixes());
+
+      // Template data file paths
       let filePathNoExt = parsed.dir + "/" + fileNameNoExt;
-      let dataSuffix = this.config.jsDataFileSuffix;
-      debug("Using %o to find data files.", dataSuffix);
-
       this._addBaseToPaths(paths, filePathNoExt, userExtensions);
 
+      // Directory data file paths
       let allDirs = TemplatePath.getAllDirs(parsed.dir);
@@ -602,4 +633,9 @@
         }
-        if (!inputDir || (dir.indexOf(inputDir) === 0 && dir !== inputDir)) {
-          this._addBaseToPaths(paths, dirPathNoExt, userExtensions);
+        if (!inputDir || (dir.startsWith(inputDir) && dir !== inputDir)) {
+          if (this.config.dataFileDirBaseNameOverride) {
+            let indexDataFile = dir + "/" + this.config.dataFileDirBaseNameOverride;
+            this._addBaseToPaths(paths, indexDataFile, userExtensions, true);
+          } else {
+            this._addBaseToPaths(paths, dirPathNoExt, userExtensions);
+          }
         }
@@ -614,3 +650,11 @@ }
         );
-        if (lastInputDir !== "./") {
+
+        // in root input dir, search for index.11tydata.json et al
+        if (this.config.dataFileDirBaseNameOverride) {
+          let indexDataFile =
+            TemplatePath.getDirFromFilePath(lastInputDir) +
+            "/" +
+            this.config.dataFileDirBaseNameOverride;
+          this._addBaseToPaths(paths, indexDataFile, userExtensions, true);
+        } else if (lastInputDir !== "./") {
           this._addBaseToPaths(paths, lastInputDir, userExtensions);
@@ -622,3 +666,3 @@ }
     debug("getLocalDataPaths(%o): %o", templatePath, paths);
-    return lodashUniq(paths).reverse();
+    return unique(paths).reverse();
   }
@@ -639,3 +683,3 @@
   static cleanupData(data) {
-    if ("tags" in data) {
+    if (isPlainObject(data) && "tags" in data) {
       if (typeof data.tags === "string") {
@@ -654,11 +698,5 @@ data.tags = data.tags ? [data.tags] : [];
 
-  getServerlessPathData() {
-    if (
-      this.configApiGlobalData &&
-      this.configApiGlobalData.eleventy &&
-      this.configApiGlobalData.eleventy.serverless &&
-      this.configApiGlobalData.eleventy.serverless.path
-    ) {
-      return this.configApiGlobalData.eleventy.serverless.path;
-    }
+  async getServerlessPathData() {
+    let configApiGlobalData = await this.getInitialGlobalData();
+    return configApiGlobalData?.eleventy?.serverless?.path;
   }
@@ -665,0 +703,0 @@ }

src/TemplateEngineManager.js

@@ -14,2 +14,12 @@ const EleventyBaseError = require("./EleventyBaseError");
 
+  static isCustomEngineSimpleAlias(entry) {
+    let keys = Object.keys(entry);
+    if (keys.length > 2) {
+      return false;
+    }
+    return !keys.some((key) => {
+      return key !== "key" && key !== "extension";
+    });
+  }
+
   get keyToClassNameMap() {
@@ -30,5 +40,19 @@ if (!this._keyToClassNameMap) {
 
+      // Custom entries *can* overwrite default entries above
       if ("extensionMap" in this.config) {
         for (let entry of this.config.extensionMap) {
-          this._keyToClassNameMap[entry.key] = "Custom";
+          // either the key does not already exist or it is not a simple alias and is an override: https://www.11ty.dev/docs/languages/custom/#overriding-an-existing-template-language
+          if (
+            !this._keyToClassNameMap[entry.key] ||
+            !TemplateEngineManager.isCustomEngineSimpleAlias(entry)
+          ) {
+            // throw an error if you try to override a Custom engine, this is a short term error until we swap this to use the extension instead of the key to get the class
+            if (this._keyToClassNameMap[entry.key] === "Custom") {
+              throw new Error(
+                `An attempt was made to override the *already* overridden "${entry.key}" template syntax via the \`addExtension\` configuration API. A maximum of one override is currently supported. If you’re trying to add an alias to an existing syntax, make sure only the \`key\` property is present in the addExtension options object.`
+              );
+            }
+
+            this._keyToClassNameMap[entry.key] = "Custom";
+          }
         }
@@ -88,2 +112,4 @@ }
 
+    // TODO these cached engines should be based on extensions not name, then we can remove the error in
+    //  "Double override (not aliases) throws an error" test in TemplateRenderCustomTest.js
     if (this.engineCache[name]) {
@@ -99,3 +125,3 @@ return this.engineCache[name];
 
-    // If the user providers a "Custom" engine using addExtension,
+    // If provided a "Custom" engine using addExtension,
     // But that engine's instance is *not* custom,
@@ -102,0 +128,0 @@ // The user must be overriding an existing engine

src/TemplateFileSlug.js

@@ -21,2 +21,3 @@ const path = require("path");
 
+  // `page.filePathStem` see https://www.11ty.dev/docs/data-eleventy-supplied/#page-variable
   getFullPathWithoutExtension() {
@@ -28,2 +29,7 @@ return "/" + TemplatePath.join(...this.dirs, this._getRawSlug());
     let slug = this.filenameNoExt;
+    return this._stripDateFromSlug(slug);
+  }
+
+  /** Removes dates in the format of YYYY-MM-DD from a given slug string candidate. */
+  _stripDateFromSlug(slug) {
     let reg = slug.match(/\d{4}-\d{2}-\d{2}-(.*)/);
@@ -36,2 +42,3 @@ if (reg) {
 
+  // `page.fileSlug` see https://www.11ty.dev/docs/data-eleventy-supplied/#page-variable
   getSlug() {
@@ -41,3 +48,7 @@ let rawSlug = this._getRawSlug();
     if (rawSlug === "index") {
-      return this.dirs.length ? this.dirs[this.dirs.length - 1] : "";
+      if (!this.dirs.length) {
+        return "";
+      }
+      let lastDir = this.dirs[this.dirs.length - 1];
+      return this._stripDateFromSlug(lastDir);
     }
@@ -44,0 +55,0 @@

src/TemplateGlob.js

@@ -18,3 +18,3 @@ const { TemplatePath } = require("@11ty/eleventy-utils");
     if (path.charAt(0) === "!") {
-      return "!" + TemplateGlob.normalizePath(path.substr(1));
+      return "!" + TemplateGlob.normalizePath(path.slice(1));
     } else {
@@ -21,0 +21,0 @@ return TemplateGlob.normalizePath(path);

src/TemplateLayout.js

@@ -17,8 +17,4 @@ const { TemplatePath } = require("@11ty/eleventy-utils");
 
-    let resolvedPath = new TemplateLayoutPathResolver(
-      key,
-      inputDir,
-      extensionMap,
-      config
-    ).getFullPath();
+    let resolver = new TemplateLayoutPathResolver(key, inputDir, extensionMap, config);
+    let resolvedPath = resolver.getFullPath();
 
@@ -30,3 +26,5 @@ super(resolvedPath, inputDir, config);
     }
+
     this.extensionMap = extensionMap;
+    this.key = resolver.getNormalizedLayoutKey();
     this.dataKeyLayoutPath = key;
@@ -37,2 +35,14 @@ this.inputPath = resolvedPath;
 
+  getKey() {
+    return this.key;
+  }
+
+  getFullKey() {
+    return TemplateLayout.resolveFullKey(this.dataKeyLayoutPath, this.inputDir);
+  }
+
+  getCacheKeys() {
+    return new Set([this.dataKeyLayoutPath, this.getFullKey(), this.key]);
+  }
+
   static resolveFullKey(key, inputDir) {
@@ -43,17 +53,17 @@ return TemplatePath.join(inputDir, key);
   static getTemplate(key, inputDir, config, extensionMap) {
-    if (config.useTemplateCache) {
-      let fullKey = TemplateLayout.resolveFullKey(key, inputDir);
-      if (templateCache.has(fullKey)) {
-        debugDev("Found %o in TemplateCache", key);
-        return templateCache.get(fullKey);
-      }
+    if (!config.useTemplateCache) {
+      return new TemplateLayout(key, inputDir, extensionMap, config);
+    }
 
-      let tmpl = new TemplateLayout(key, inputDir, extensionMap, config);
+    let fullKey = TemplateLayout.resolveFullKey(key, inputDir);
+    if (!templateCache.has(fullKey)) {
+      let layout = new TemplateLayout(key, inputDir, extensionMap, config);
+
+      templateCache.add(layout);
       debugDev("Added %o to TemplateCache", key);
-      templateCache.add(fullKey, tmpl);
 
-      return tmpl;
-    } else {
-      return new TemplateLayout(key, inputDir, extensionMap, config);
+      return layout;
     }
+
+    return templateCache.get(fullKey);
   }
@@ -63,5 +73,7 @@
     return {
+      // Used by `TemplateLayout.getTemplate()`
       key: this.dataKeyLayoutPath,
       inputDir: this.inputDir,
-      template: this,
+
+      // used by `this.getData()`
       frontMatterData: await this.getFrontMatterData(),
@@ -72,72 +84,136 @@ };
   async getTemplateLayoutMap() {
-    if (this.mapCache) {
-      return this.mapCache;
+    if (!this.cachedLayoutMap) {
+      this.cachedLayoutMap = new Promise(async (resolve, reject) => {
+        try {
+          // For both the eleventy.layouts event and cyclical layout chain checking  (e.g., a => b => c => a)
+          let layoutChain = new Set();
+          layoutChain.add(this.inputPath);
+
+          let cfgKey = this.config.keys.layout;
+          let map = [];
+          let mapEntry = await this.getTemplateLayoutMapEntry();
+
+          map.push(mapEntry);
+
+          while (mapEntry.frontMatterData && cfgKey in mapEntry.frontMatterData) {
+            // Layout of the current layout
+            let parentLayoutKey = mapEntry.frontMatterData[cfgKey];
+
+            let layout = TemplateLayout.getTemplate(
+              parentLayoutKey,
+              mapEntry.inputDir,
+              this.config,
+              this.extensionMap
+            );
+
+            // Abort if a circular layout chain is detected. Otherwise, we'll time out and run out of memory.
+            if (layoutChain.has(layout.inputPath)) {
+              throw new Error(
+                `Your layouts have a circular reference, starting at ${map[0].key}! The layout at ${layout.inputPath} was specified twice in this layout chain.`
+              );
+            }
+
+            // Keep track of this layout so we can detect duplicates in subsequent iterations
+            layoutChain.add(layout.inputPath);
+
+            // reassign for next loop
+            mapEntry = await layout.getTemplateLayoutMapEntry();
+
+            map.push(mapEntry);
+          }
+
+          this.layoutChain = Array.from(layoutChain);
+
+          resolve(map);
+        } catch (e) {
+          reject(e);
+        }
+      });
     }
 
-    let cfgKey = this.config.keys.layout;
-    let map = [];
-    let mapEntry = await this.getTemplateLayoutMapEntry();
-    map.push(mapEntry);
+    return this.cachedLayoutMap;
+  }
 
-    while (mapEntry.frontMatterData && cfgKey in mapEntry.frontMatterData) {
-      let layout = TemplateLayout.getTemplate(
-        mapEntry.frontMatterData[cfgKey],
-        mapEntry.inputDir,
-        this.config,
-        this.extensionMap
-      );
-      mapEntry = await layout.getTemplateLayoutMapEntry();
-      map.push(mapEntry);
+  async getLayoutChain() {
+    if (!Array.isArray(this.layoutChain)) {
+      await this.getTemplateLayoutMap();
     }
 
-    this.mapCache = map;
-    return map;
+    return this.layoutChain;
   }
 
   async getData() {
-    if (this.dataCache) {
-      return this.dataCache;
-    }
+    if (!this.dataCache) {
+      this.dataCache = new Promise(async (resolve, reject) => {
+        try {
+          let map = await this.getTemplateLayoutMap();
+          let dataToMerge = [];
+          for (let j = map.length - 1; j >= 0; j--) {
+            dataToMerge.push(map[j].frontMatterData);
+          }
 
-    let map = await this.getTemplateLayoutMap();
-    let dataToMerge = [];
-    let layoutChain = [];
-    for (let j = map.length - 1; j >= 0; j--) {
-      layoutChain.push(map[j].template.inputPath);
-      dataToMerge.push(map[j].frontMatterData);
+          // Deep merge of layout front matter
+          let data = TemplateData.mergeDeep(this.config, {}, ...dataToMerge);
+          delete data[this.config.keys.layout];
+
+          resolve(data);
+        } catch (e) {
+          reject(e);
+        }
+      });
     }
 
-    // Deep merge of layout front matter
-    let data = TemplateData.mergeDeep(this.config, {}, ...dataToMerge);
-    delete data[this.config.keys.layout];
-
-    this.layoutChain = layoutChain.reverse();
-    this.dataCache = data;
-    return data;
+    return this.dataCache;
   }
 
-  async _testGetLayoutChain() {
-    if (!this.layoutChain) {
-      await this.getData();
+  // Do only cache this layout’s render function and delegate the rest to the other templates.
+  async getCachedCompiledLayoutFunction() {
+    if (!this.cachedCompiledLayoutFunction) {
+      this.cachedCompiledLayoutFunction = new Promise(async (resolve, reject) => {
+        try {
+          let rawInput = await this.getPreRender();
+          let renderFunction = await this.compile(rawInput);
+          resolve(renderFunction);
+        } catch (e) {
+          reject(e);
+        }
+      });
     }
-    return this.layoutChain;
+
+    return this.cachedCompiledLayoutFunction;
   }
 
-  async getCompiledLayoutFunctions(layoutMap) {
+  async getCompiledLayoutFunctions() {
+    let layoutMap = await this.getTemplateLayoutMap();
     let fns = [];
+
     try {
-      for (let layoutEntry of layoutMap) {
-        fns.push(
-          await layoutEntry.template.compile(
-            await layoutEntry.template.getPreRender()
-          )
+      fns.push({
+        render: await this.getCachedCompiledLayoutFunction(),
+      });
+
+      if (layoutMap.length > 1) {
+        let [currentLayout, parentLayout] = layoutMap;
+        let { key, inputDir } = parentLayout;
+
+        let layoutTemplate = TemplateLayout.getTemplate(
+          key,
+          inputDir,
+          this.config,
+          this.extensionMap
         );
+
+        // The parent already includes the rest of the layout chain
+        let upstreamFns = await layoutTemplate.getCompiledLayoutFunctions();
+        for (let j = 0, k = upstreamFns.length; j < k; j++) {
+          fns.push(upstreamFns[j]);
+        }
       }
+
+      return fns;
     } catch (e) {
       debugDev("Clearing TemplateCache after error.");
       templateCache.clear();
-      return Promise.reject(e);
+      throw e;
     }
-
-    return fns;
   }
@@ -151,5 +227,2 @@
       data.layoutContent = templateContent;
-
-      // deprecated
-      data._layoutContent = templateContent;
     }
@@ -162,9 +235,10 @@
   // Trouble: layouts may need data variables present downstream/upstream
+  // This is called from Template->renderPageEntry
   async render(data, templateContent) {
     data = TemplateLayout.augmentDataWithContent(data, templateContent);
 
-    let layoutMap = await this.getTemplateLayoutMap();
-    let fns = await this.getCompiledLayoutFunctions(layoutMap);
-    for (let fn of fns) {
-      templateContent = await fn(data);
+    let compiledFunctions = await this.getCompiledLayoutFunctions();
+
+    for (let { render } of compiledFunctions) {
+      templateContent = await render(data);
       data = TemplateLayout.augmentDataWithContent(data, templateContent);
@@ -175,4 +249,13 @@ }
   }
+
+  resetCaches(types) {
+    super.resetCaches(types);
+
+    delete this.dataCache;
+    delete this.layoutChain;
+    delete this.cachedLayoutMap;
+    delete this.cachedCompiledLayoutFunction;
+  }
 }
 
 module.exports = TemplateLayout;

src/TemplateLayoutPathResolver.js

@@ -9,5 +9,3 @@ const fs = require("fs");
     if (!config) {
-      throw new Error(
-        "Expected `config` in TemplateLayoutPathResolver constructor"
-      );
+      throw new Error("Expected `config` in TemplateLayoutPathResolver constructor");
     }
@@ -21,5 +19,3 @@ this._config = config;
     if (!extensionMap) {
-      throw new Error(
-        "Expected `extensionMap` in TemplateLayoutPathResolver constructor."
-      );
+      throw new Error("Expected `extensionMap` in TemplateLayoutPathResolver constructor.");
     }
@@ -30,2 +26,6 @@
 
+  setAliases() {
+    this.aliases = Object.assign({}, this.config.layoutAliases, this.aliases);
+  }
+
   set inputDir(dir) {
@@ -65,16 +65,12 @@ this._inputDir = dir;
 
+    let useLayoutResolution = this.config.layoutResolution;
+
     this.pathAlreadyHasExtension = this.dir + "/" + this.path;
-    if (
-      this.path.split(".").length > 0 &&
-      fs.existsSync(this.pathAlreadyHasExtension)
-    ) {
+
+    if (this.path.split(".").length > 0 && fs.existsSync(this.pathAlreadyHasExtension)) {
       this.filename = this.path;
-      this.fullPath = TemplatePath.addLeadingDotSlash(
-        this.pathAlreadyHasExtension
-      );
-    } else {
+      this.fullPath = TemplatePath.addLeadingDotSlash(this.pathAlreadyHasExtension);
+    } else if (useLayoutResolution) {
       this.filename = this.findFileName();
-      this.fullPath = TemplatePath.addLeadingDotSlash(
-        this.dir + "/" + this.filename
-      );
+      this.fullPath = TemplatePath.addLeadingDotSlash(this.dir + "/" + this.filename);
     }
@@ -110,6 +106,3 @@ }
       throw Error(
-        "TemplateLayoutPathResolver directory does not exist for " +
-          this.path +
-          ": " +
-          this.dir
+        "TemplateLayoutPathResolver directory does not exist for " + this.path + ": " + this.dir
       );
@@ -139,4 +132,8 @@ }
   }
+
+  getNormalizedLayoutKey() {
+    return TemplatePath.stripLeadingSubPath(this.fullPath, this.getLayoutsDir());
+  }
 }
 
 module.exports = TemplateLayoutPathResolver;

src/TemplateMap.js

@@ -1,11 +0,13 @@
-const isPlainObject = require("./Util/IsPlainObject");
 const DependencyGraph = require("dependency-graph").DepGraph;
+const { isPlainObject } = require("@11ty/eleventy-utils");
+
 const TemplateCollection = require("./TemplateCollection");
 const EleventyErrorUtil = require("./EleventyErrorUtil");
+
 const UsingCircularTemplateContentReferenceError = require("./Errors/UsingCircularTemplateContentReferenceError");
+const EleventyBaseError = require("./EleventyBaseError");
+
 const debug = require("debug")("Eleventy:TemplateMap");
 const debugDev = require("debug")("Dev:Eleventy:TemplateMap");
 
-const EleventyBaseError = require("./EleventyBaseError");
-
 class TemplateMapConfigError extends EleventyBaseError {}
@@ -53,3 +55,3 @@
 
-  get tagPrefix() {
+  static get tagPrefix() {
     return "___TAG___";
@@ -59,4 +61,10 @@ }
   async add(template) {
-    // getTemplateMapEntries is where the Template.getData is first generated
-    for (let map of await template.getTemplateMapEntries()) {
+    if (!template) {
+      return;
+    }
+
+    // IMPORTANT: This is where the data is first generated for the template
+    let data = await template.getData();
+
+    for (let map of await template.getTemplateMapEntries(data)) {
       this.map.push(map);
@@ -72,3 +80,3 @@ }
     if (str.startsWith("collections.")) {
-      return str.substr("collections.".length);
+      return str.slice("collections.".length);
     }
@@ -97,5 +105,42 @@ }
 
+  addTagsToGraph(graph, inputPath, tags) {
+    if (!Array.isArray(tags)) {
+      return;
+    }
+    for (let tag of tags) {
+      let tagWithPrefix = TemplateMap.tagPrefix + tag;
+      if (!graph.hasNode(tagWithPrefix)) {
+        graph.addNode(tagWithPrefix);
+      }
+
+      // Populates to collections.tagName
+      // Dependency from tag to inputPath
+      graph.addDependency(tagWithPrefix, inputPath);
+    }
+  }
+
+  addDeclaredDependenciesToGraph(graph, inputPath, deps) {
+    if (!Array.isArray(deps)) {
+      return;
+    }
+
+    for (let tag of deps) {
+      let tagWithPrefix = TemplateMap.tagPrefix + tag;
+      if (!graph.hasNode(tagWithPrefix)) {
+        graph.addNode(tagWithPrefix);
+      }
+
+      // Dependency from inputPath to collection/tag
+      graph.addDependency(inputPath, tagWithPrefix);
+    }
+  }
+
+  // Exclude: Pagination templates consuming `collections` or `collections.all`
+  // Exclude: Pagination templates that consume config API collections
+
+  // Include: Pagination templates that don’t consume config API collections
+  // Include: Templates that don’t use Pagination
   getMappedDependencies() {
     let graph = new DependencyGraph();
-    let tagPrefix = this.tagPrefix;
+    let tagPrefix = TemplateMap.tagPrefix;
 
@@ -129,26 +174,23 @@ graph.addNode(tagPrefix + "all");
       if (!entry.data.eleventyExcludeFromCollections) {
-        // collections.all
+        // Populates to collections.all
         graph.addDependency(tagPrefix + "all", entry.inputPath);
 
-        if (entry.data.tags) {
-          for (let tag of entry.data.tags) {
-            let tagWithPrefix = tagPrefix + tag;
-            if (!graph.hasNode(tagWithPrefix)) {
-              graph.addNode(tagWithPrefix);
-            }
+        this.addTagsToGraph(graph, entry.inputPath, entry.data.tags);
+      }
 
-            // collections.tagName
-            // Dependency from tag to inputPath
-            graph.addDependency(tagWithPrefix, entry.inputPath);
-          }
-        }
-      }
+      this.addDeclaredDependenciesToGraph(
+        graph,
+        entry.inputPath,
+        entry.data.eleventyImport?.collections
+      );
     }
 
-    return graph.overallOrder();
+    return graph;
   }
 
+  // Exclude: Pagination templates consuming `collections` or `collections.all`
+  // Include: Pagination templates that consume config API collections
   getDelayedMappedDependencies() {
     let graph = new DependencyGraph();
-    let tagPrefix = this.tagPrefix;
+    let tagPrefix = TemplateMap.tagPrefix;
 
@@ -162,3 +204,2 @@ graph.addNode(tagPrefix + "all");
       graph.addNode(tagPrefix + tag);
-      // graph.addDependency( tagPrefix + tag, tagPrefix + "all" );
     }
@@ -172,6 +213,3 @@
       let paginationTagTarget = this.getPaginationTagTarget(entry);
-      if (
-        paginationTagTarget &&
-        this.isUserConfigCollectionName(paginationTagTarget)
-      ) {
+      if (paginationTagTarget && this.isUserConfigCollectionName(paginationTagTarget)) {
         if (!graph.hasNode(entry.inputPath)) {
@@ -183,33 +221,28 @@ graph.addNode(entry.inputPath);
         if (!entry.data.eleventyExcludeFromCollections) {
-          // collections.all
+          // Populates into collections.all
           graph.addDependency(tagPrefix + "all", entry.inputPath);
 
-          if (entry.data.tags) {
-            for (let tag of entry.data.tags) {
-              let tagWithPrefix = tagPrefix + tag;
-              if (!graph.hasNode(tagWithPrefix)) {
-                graph.addNode(tagWithPrefix);
-              }
-              // collections.tagName
-              // Dependency from tag to inputPath
-              graph.addDependency(tagWithPrefix, entry.inputPath);
-            }
-          }
+          this.addTagsToGraph(graph, entry.inputPath, entry.data.tags);
         }
+
+        this.addDeclaredDependenciesToGraph(
+          graph,
+          entry.inputPath,
+          entry.data.eleventyImport?.collections
+        );
       }
     }
-    let order = graph.overallOrder();
-    return order;
+
+    return graph;
   }
 
+  // Exclude: Pagination templates consuming `collections.all`
+  // Include: Pagination templates consuming `collections`
   getPaginatedOverCollectionsMappedDependencies() {
     let graph = new DependencyGraph();
-    let tagPrefix = this.tagPrefix;
+    let tagPrefix = TemplateMap.tagPrefix;
     let allNodeAdded = false;
 
     for (let entry of this.map) {
-      if (
-        this.isPaginationOverAllCollections(entry) &&
-        !this.getPaginationTagTarget(entry)
-      ) {
+      if (this.isPaginationOverAllCollections(entry) && !this.getPaginationTagTarget(entry)) {
         if (!allNodeAdded) {
@@ -227,12 +260,22 @@ graph.addNode(tagPrefix + "all");
           graph.addDependency(tagPrefix + "all", entry.inputPath);
+
+          // Note that `tags` are otherwise ignored here
+          // TODO should we throw an error?
         }
+
+        this.addDeclaredDependenciesToGraph(
+          graph,
+          entry.inputPath,
+          entry.data.eleventyImport?.collections
+        );
       }
     }
 
-    return graph.overallOrder();
+    return graph;
   }
 
+  // Include: Pagination templates consuming `collections.all`
   getPaginatedOverAllCollectionMappedDependencies() {
     let graph = new DependencyGraph();
-    let tagPrefix = this.tagPrefix;
+    let tagPrefix = TemplateMap.tagPrefix;
     let allNodeAdded = false;
@@ -255,17 +298,96 @@
         if (!entry.data.eleventyExcludeFromCollections) {
-          // collections.all
+          // Populates into collections.all
+          // This is circular!
           graph.addDependency(tagPrefix + "all", entry.inputPath);
+
+          // Note that `tags` are otherwise ignored here
+          // TODO should we throw an error?
         }
+
+        this.addDeclaredDependenciesToGraph(
+          graph,
+          entry.inputPath,
+          entry.data.eleventyImport?.collections
+        );
       }
     }
 
-    return graph.overallOrder();
+    return graph;
   }
 
+  getTemplateMapDependencyGraph() {
+    return [
+      this.getMappedDependencies(),
+      this.getDelayedMappedDependencies(),
+      this.getPaginatedOverCollectionsMappedDependencies(),
+      this.getPaginatedOverAllCollectionMappedDependencies(),
+    ];
+  }
+
+  getFullTemplateMapOrder() {
+    // convert dependency graphs to ordered arrays
+    return this.getTemplateMapDependencyGraph().map((entry) => entry.overallOrder());
+  }
+
+  setupDependencyGraphChangesForIncrementalFile(incrementalFile) {
+    if (!incrementalFile) {
+      return new Set();
+    }
+
+    // Only dependents: things that consume templates that have deleted dependencies, e.g. if index.md consumes collections.post and a file removes its post tag, regenerate index.md
+    let newCollectionNames = new Set(); // collections published to
+    for (let entry of this.map) {
+      if (!entry.data.eleventyExcludeFromCollections) {
+        newCollectionNames.add("all");
+
+        if (Array.isArray(entry.data.tags)) {
+          for (let tag of entry.data.tags) {
+            newCollectionNames.add(tag);
+          }
+        }
+      }
+    }
+
+    let deletedCollectionNames = this.config.uses.findCollectionsRemovedFrom(
+      incrementalFile,
+      newCollectionNames
+    );
+
+    // Delete incremental from the dependency graph so we get fresh entries!
+    // This _must_ happen before any additions, the other ones are in Custom.js and GlobalDependencyMap.js (from the eleventy.layouts Event)
+    this.config.uses.resetNode(incrementalFile);
+
+    return this.config.uses.getTemplatesThatConsumeCollections(deletedCollectionNames);
+  }
+
+  // Similar to getTemplateMapDependencyGraph but adds those relationships to the global dependency graph used for incremental builds
+  addToGlobalDependencyGraph() {
+    for (let entry of this.map) {
+      let paginationTagTarget = this.getPaginationTagTarget(entry);
+      if (paginationTagTarget) {
+        this.config.uses.addDependencyConsumesCollection(entry.inputPath, paginationTagTarget);
+      }
+
+      if (!entry.data.eleventyExcludeFromCollections) {
+        this.config.uses.addDependencyPublishesToCollection(entry.inputPath, "all");
+
+        if (Array.isArray(entry.data.tags)) {
+          for (let tag of entry.data.tags) {
+            this.config.uses.addDependencyPublishesToCollection(entry.inputPath, tag);
+          }
+        }
+      }
+
+      if (Array.isArray(entry.data.eleventyImport?.collections)) {
+        for (let tag of entry.data.eleventyImport.collections) {
+          this.config.uses.addDependencyConsumesCollection(entry.inputPath, tag);
+        }
+      }
+    }
+  }
+
   async setCollectionByTagName(tagName) {
     if (this.isUserConfigCollectionName(tagName)) {
       // async
-      this.collectionsData[tagName] = await this.getUserConfigCollection(
-        tagName
-      );
+      this.collectionsData[tagName] = await this.getUserConfigCollection(tagName);
     } else {
@@ -289,7 +411,7 @@ this.collectionsData[tagName] = this.getTaggedCollection(tagName);
   async initDependencyMap(dependencyMap) {
-    let tagPrefix = this.tagPrefix;
+    let tagPrefix = TemplateMap.tagPrefix;
     for (let depEntry of dependencyMap) {
       if (depEntry.startsWith(tagPrefix)) {
         // is a tag (collection) entry
-        let tagName = depEntry.substr(tagPrefix.length);
+        let tagName = depEntry.slice(tagPrefix.length);
         await this.setCollectionByTagName(tagName);
@@ -307,5 +429,3 @@ } else {
           // We want these empty-data pagination templates to show up in the serverlessUrlMap.
-          map.template.initServerlessUrlsForEmptyPaginationTemplates(
-            map.data.permalink
-          );
+          await map.template.initServerlessUrlsForEmptyPaginationTemplates(map.data.permalink);
         } else {
@@ -321,4 +441,3 @@ let counter = 0;
               counter === 0 ||
-              (map.data.pagination &&
-                map.data.pagination.addAllPagesToCollections)
+              (map.data.pagination && map.data.pagination.addAllPagesToCollections)
             ) {
@@ -345,14 +464,8 @@ if (!map.data.eleventyExcludeFromCollections) {
 
-    let dependencyMap = this.getMappedDependencies();
+    let [dependencyMap, delayedDependencyMap, firstPaginatedDepMap, secondPaginatedDepMap] =
+      this.getFullTemplateMapOrder();
+
     await this.initDependencyMap(dependencyMap);
-
-    let delayedDependencyMap = this.getDelayedMappedDependencies();
     await this.initDependencyMap(delayedDependencyMap);
-
-    let firstPaginatedDepMap =
-      this.getPaginatedOverCollectionsMappedDependencies();
     await this.initDependencyMap(firstPaginatedDepMap);
-
-    let secondPaginatedDepMap =
-      this.getPaginatedOverAllCollectionMappedDependencies();
     await this.initDependencyMap(secondPaginatedDepMap);
@@ -368,8 +481,14 @@
     );
-    let orderedMap = orderedPaths.map(
-      function (inputPath) {
-        return this.getMapEntryForInputPath(inputPath);
-      }.bind(this)
-    );
 
+    let orderedMap = orderedPaths.map((inputPath) => {
+      return this.getMapEntryForInputPath(inputPath);
+    });
+
+    await this.config.events.emitLazy("eleventy.contentMap", () => {
+      return {
+        inputPathToUrl: this.generateInputUrlContentMap(orderedMap),
+        urlToInputPath: this.generateUrlMap(orderedMap),
+      };
+    });
+
     await this.populateContentDataInMap(orderedMap);
@@ -382,4 +501,5 @@
 
-    await this.config.events.emit(
-      "eleventy.serverlessUrlMap",
+    await this.config.events.emitLazy("eleventy.layouts", () => this.generateLayoutsMap());
+
+    await this.config.events.emitLazy("eleventy.serverlessUrlMap", () =>
       this.generateServerlessUrlMap(orderedMap)
@@ -389,2 +509,21 @@ );
 
+  generateInputUrlContentMap(orderedMap) {
+    let entries = {};
+    for (let entry of orderedMap) {
+      entries[entry.inputPath] = entry._pages.map((entry) => entry.url);
+    }
+    return entries;
+  }
+
+  generateUrlMap(orderedMap) {
+    let entries = {};
+    for (let entry of orderedMap) {
+      for (let page of entry._pages) {
+        // duplicate urls throw an error, so we can return non array here
+        entries[page.url] = entry.inputPath;
+      }
+    }
+    return entries;
+  }
+
   generateServerlessUrlMap(orderedMap) {
@@ -433,31 +572,14 @@ let entries = [];
 
-  getOrderedInputPaths(
-    dependencyMap,
-    delayedDependencyMap,
-    firstPaginatedDepMap,
-    secondPaginatedDepMap
-  ) {
+  // Filter out any tag nodes
+  getOrderedInputPaths(...maps) {
     let orderedMap = [];
-    let tagPrefix = this.tagPrefix;
+    let tagPrefix = TemplateMap.tagPrefix;
 
-    for (let dep of dependencyMap) {
-      if (!dep.startsWith(tagPrefix)) {
-        orderedMap.push(dep);
+    for (let map of maps) {
+      for (let dep of map) {
+        if (!dep.startsWith(tagPrefix)) {
+          orderedMap.push(dep);
+        }
       }
     }
-    for (let dep of delayedDependencyMap) {
-      if (!dep.startsWith(tagPrefix)) {
-        orderedMap.push(dep);
-      }
-    }
-    for (let dep of firstPaginatedDepMap) {
-      if (!dep.startsWith(tagPrefix)) {
-        orderedMap.push(dep);
-      }
-    }
-    for (let dep of secondPaginatedDepMap) {
-      if (!dep.startsWith(tagPrefix)) {
-        orderedMap.push(dep);
-      }
-    }
     return orderedMap;
@@ -472,2 +594,3 @@ }
       }
+
       if (!map.template.behavior.isRenderable()) {
@@ -478,7 +601,6 @@ // Note that empty pagination templates will be skipped here as not renderable
 
+      // IMPORTANT: this is where template content is rendered
       try {
         for (let pageEntry of map._pages) {
-          pageEntry.templateContent = await map.template.getTemplateMapContent(
-            pageEntry
-          );
+          pageEntry.templateContent = await pageEntry.template.renderWithoutLayout(pageEntry.data);
         }
@@ -492,5 +614,3 @@ } catch (e) {
       }
-      debugDev(
-        "Added this.map[...].templateContent, outputPath, et al for one map entry"
-      );
+      debugDev("Added this.map[...].templateContent, outputPath, et al for one map entry");
     }
@@ -501,5 +621,3 @@
         for (let pageEntry of map._pages) {
-          pageEntry.templateContent = await map.template.getTemplateMapContent(
-            pageEntry
-          );
+          pageEntry.templateContent = await pageEntry.template.renderWithoutLayout(pageEntry.data);
         }
@@ -562,4 +680,3 @@ } catch (e) {
   isUserConfigCollectionName(name) {
-    let collections =
-      this.configCollections || this.userConfig.getCollections();
+    let collections = this.configCollections || this.userConfig.getCollections();
     return name && !!collections[name];
@@ -569,10 +686,7 @@ }
   getUserConfigCollectionNames() {
-    return Object.keys(
-      this.configCollections || this.userConfig.getCollections()
-    );
+    return Object.keys(this.configCollections || this.userConfig.getCollections());
   }
 
   async getUserConfigCollection(name) {
-    let configCollections =
-      this.configCollections || this.userConfig.getCollections();
+    let configCollections = this.configCollections || this.userConfig.getCollections();
 
@@ -588,4 +702,3 @@ // This works with async now
     let collections = {};
-    let configCollections =
-      this.configCollections || this.userConfig.getCollections();
+    let configCollections = this.configCollections || this.userConfig.getCollections();
 
@@ -595,5 +708,3 @@ for (let name in configCollections) {
 
-      debug(
-        `Collection: collections.${name} size: ${collections[name].length}`
-      );
+      debug(`Collection: collections.${name} size: ${collections[name].length}`);
     }
@@ -645,3 +756,5 @@
       for (let page of entry._pages) {
-        promises.push(page.template.resolveRemainingComputedData(page.data));
+        if (this.config.keys.computed in page.data) {
+          promises.push(page.template.resolveRemainingComputedData(page.data));
+        }
       }
@@ -652,2 +765,34 @@ }
 
+  async generateLayoutsMap() {
+    let layouts = {};
+
+    for (let entry of this.map) {
+      for (let page of entry._pages) {
+        let tmpl = page.template;
+        let layoutKey = page.data[this.config.keys.layout];
+        if (layoutKey) {
+          let layout = tmpl.getLayout(layoutKey);
+          let layoutChain = await layout.getLayoutChain();
+          let priors = [];
+          for (let filepath of layoutChain) {
+            if (!layouts[filepath]) {
+              layouts[filepath] = new Set();
+            }
+            layouts[filepath].add(page.inputPath);
+            for (let prior of priors) {
+              layouts[filepath].add(prior);
+            }
+            priors.push(filepath);
+          }
+        }
+      }
+    }
+
+    for (let key in layouts) {
+      layouts[key] = Array.from(layouts[key]);
+    }
+
+    return layouts;
+  }
+
   checkForDuplicatePermalinks() {
@@ -660,12 +805,10 @@ let permalinks = {};
           // do nothing (also serverless)
-        } else if (!permalinks[page.url]) {
-          permalinks[page.url] = [entry.inputPath];
+        } else if (!permalinks[page.outputPath]) {
+          permalinks[page.outputPath] = [entry.inputPath];
         } else {
-          warnings[
+          warnings[page.outputPath] = `Output conflict: multiple input files are writing to \`${
             page.outputPath
-          ] = `Output conflict: multiple input files are writing to \`${
-            page.outputPath
           }\`. Use distinct \`permalink\` values to resolve this conflict.
   1. ${entry.inputPath}
-${permalinks[page.url]
+${permalinks[page.outputPath]
   .map(function (inputPath, index) {
@@ -677,3 +820,3 @@ return `  ${index + 2}. ${inputPath}\n`;
 
-          permalinks[page.url].push(entry.inputPath);
+          permalinks[page.outputPath].push(entry.inputPath);
         }
@@ -680,0 +823,0 @@ }

src/TemplatePassthrough.js

@@ -5,8 +5,9 @@ const fs = require("fs");
 const copy = require("recursive-copy");
-const fastglob = require("fast-glob");
 const { TemplatePath } = require("@11ty/eleventy-utils");
 
-const debug = require("debug")("Eleventy:TemplatePassthrough");
 const EleventyBaseError = require("./EleventyBaseError");
+const checkPassthroughCopyBehavior = require("./Util/PassthroughCopyBehaviorCheck");
 
+const debug = require("debug")("Eleventy:TemplatePassthrough");
+
 class TemplatePassthroughError extends EleventyBaseError {}
@@ -34,2 +35,4 @@
 
+    this.copyOptions = path.copyOptions; // custom options for recursive-copy
+
     this.isDryRun = false;
@@ -39,2 +42,3 @@ this.isIncremental = false;
 
+  /* { inputPath, outputPath } though outputPath is *not* the full path: just the output directory */
   getPath() {
@@ -45,3 +49,3 @@ return this.rawPath;
   getOutputPath(inputFileFromGlob) {
-    const { inputDir, outputDir, outputPath, inputPath } = this;
+    let { inputDir, outputDir, outputPath, inputPath } = this;
 
@@ -52,6 +56,3 @@ if (outputPath === true) {
           outputDir,
-          TemplatePath.stripLeadingSubPath(
-            inputFileFromGlob || inputPath,
-            inputDir
-          )
+          TemplatePath.stripLeadingSubPath(inputFileFromGlob || inputPath, inputDir)
         )
@@ -68,11 +69,11 @@ );
     // https://github.com/11ty/eleventy/issues/2278
-    let fullOutputPath = TemplatePath.normalize(
-      TemplatePath.join(outputDir, outputPath)
-    );
+    let fullOutputPath = TemplatePath.normalize(TemplatePath.join(outputDir, outputPath));
 
-    if (this.isIncremental && TemplatePath.isDirectorySync(fullOutputPath)) {
+    if (
+      fs.existsSync(inputPath) &&
+      !TemplatePath.isDirectorySync(inputPath) &&
+      TemplatePath.isDirectorySync(fullOutputPath)
+    ) {
       let filename = path.parse(inputPath).base;
-      return TemplatePath.normalize(
-        TemplatePath.join(outputDir, outputPath, filename)
-      );
+      return TemplatePath.normalize(TemplatePath.join(fullOutputPath, filename));
     }
@@ -94,2 +95,6 @@
 
+  setRunMode(runMode) {
+    this.runMode = runMode;
+  }
+
   setIsIncremental(isIncremental) {
@@ -99,11 +104,12 @@ this.isIncremental = isIncremental;
 
+  setFileSystemSearch(fileSystemSearch) {
+    this.fileSystemSearch = fileSystemSearch;
+  }
+
   async getFiles(glob) {
     debug("Searching for: %o", glob);
-    let b = this.benchmarks.aggregate.get("Searching the file system");
+    let b = this.benchmarks.aggregate.get("Searching the file system (passthrough)");
     b.before();
-    const files = TemplatePath.addLeadingDotSlashArray(
-      await fastglob(glob, {
-        caseSensitiveMatch: false,
-        dot: true,
-      })
+    let files = TemplatePath.addLeadingDotSlashArray(
+      await this.fileSystemSearch.search("passthrough", glob)
     );
@@ -114,2 +120,44 @@ b.after();
 
+  // dir is guaranteed to exist by context
+  // dir may not be a directory
+  addTrailingSlashIfDirectory(dir) {
+    if (dir && typeof dir === "string") {
+      if (dir.endsWith(path.sep)) {
+        return dir;
+      }
+      if (fs.statSync(dir).isDirectory()) {
+        return `${dir}/`;
+      }
+    }
+    return dir;
+  }
+
+  // maps input paths to output paths
+  async getFileMap() {
+    // TODO VirtualFileSystem candidate
+    if (!isGlob(this.inputPath) && fs.existsSync(this.inputPath)) {
+      // When inputPath is a directory, make sure it has a slash for passthrough copy aliasing
+      // https://github.com/11ty/eleventy/issues/2709
+      let inputPath = this.addTrailingSlashIfDirectory(this.inputPath);
+      return [
+        {
+          inputPath,
+          outputPath: this.getOutputPath(),
+        },
+      ];
+    }
+
+    let paths = [];
+    // If not directory or file, attempt to get globs
+    let files = await this.getFiles(this.inputPath);
+    for (let inputPath of files) {
+      paths.push({
+        inputPath,
+        outputPath: this.getOutputPath(inputPath),
+      });
+    }
+
+    return paths;
+  }
+
   /* Types:
@@ -122,3 +170,3 @@ * 1. via glob, individual files found
     if (
-      !TemplatePath.stripLeadingDotSlash(dest).includes(
+      !TemplatePath.stripLeadingDotSlash(dest).startsWith(
         TemplatePath.stripLeadingDotSlash(this.outputDir)
@@ -136,3 +184,2 @@ )
     let map = {};
-
     // returns a promise
@@ -146,3 +193,3 @@ return copy(src, dest, copyOptions)
       })
-      .on(copy.events.COPY_FILE_COMPLETE, () => {
+      .on(copy.events.COPY_FILE_COMPLETE, (copyOp) => {
         fileCopyCount++;
@@ -167,26 +214,38 @@ this.benchmarks.aggregate.get("Passthrough Copy File").after();
 
-    const copyOptions = {
-      overwrite: true,
-      dot: true,
-      junk: false,
+    debug("Copying %o", this.inputPath);
+    let fileMap = await this.getFileMap();
+
+    // default options for recursive-copy
+    // see https://www.npmjs.com/package/recursive-copy#arguments
+    let copyOptionsDefault = {
+      overwrite: true, // overwrite output. fails when input is directory (mkdir) and output is file
+      dot: true, // copy dotfiles
+      junk: false, // copy cache files like Thumbs.db
       results: false,
+      expand: false, // follow symlinks (matches recursive-copy default)
+      debug: false, // (matches recursive-copy default)
+
+      // Note: `filter` callback function only passes in a relative path, which is unreliable
+      // See https://github.com/timkendrick/recursive-copy/blob/4c9a8b8a4bf573285e9c4a649a30a2b59ccf441c/lib/copy.js#L59
+      // e.g. `{ filePaths: [ './img/coolkid.jpg' ], relativePaths: [ '' ] }`
     };
-    let promises = [];
 
-    debug("Copying %o", this.inputPath);
+    let copyOptions = Object.assign(copyOptionsDefault, this.copyOptions);
 
-    if (!isGlob(this.inputPath) && fs.existsSync(this.inputPath)) {
-      promises.push(
-        this.copy(this.inputPath, this.getOutputPath(), copyOptions)
-      );
-    } else {
-      // If not directory or file, attempt to get globs
-      let files = await this.getFiles(this.inputPath);
+    let promises = fileMap.map((entry) => {
+      // For-free passthrough copy
+      if (checkPassthroughCopyBehavior(this.config, this.runMode)) {
+        let aliasMap = {};
+        aliasMap[entry.inputPath] = entry.outputPath;
 
-      promises = files.map((inputFile) => {
-        let target = this.getOutputPath(inputFile);
-        return this.copy(inputFile, target, copyOptions);
-      });
-    }
+        return Promise.resolve({
+          count: 0,
+          map: aliasMap,
+        });
+      }
 
+      // Copy the files (only in build mode)
+      return this.copy(entry.inputPath, entry.outputPath, copyOptions);
+    });
+
     // IMPORTANT: this returns an array of promises, does not await for promise to finish
@@ -210,6 +269,3 @@ return Promise.all(promises)
       .catch((err) => {
-        throw new TemplatePassthroughError(
-          `Error copying passthrough files: ${err.message}`,
-          err
-        );
+        throw new TemplatePassthroughError(`Error copying passthrough files: ${err.message}`, err);
       });
@@ -216,0 +272,0 @@ }

src/TemplatePassthroughManager.js

@@ -8,2 +8,3 @@ const multimatch = require("multimatch");
 const TemplatePassthrough = require("./TemplatePassthrough");
+const checkPassthroughCopyBehavior = require("./Util/PassthroughCopyBehaviorCheck");
 
@@ -19,5 +20,3 @@ const debug = require("debug")("Eleventy:TemplatePassthroughManager");
     if (!eleventyConfig) {
-      throw new TemplatePassthroughManagerConfigError(
-        "Missing `config` argument."
-      );
+      throw new TemplatePassthroughManagerConfigError("Missing `config` argument.");
     }
@@ -59,2 +58,6 @@ this.eleventyConfig = eleventyConfig;
 
+  setRunMode(runMode) {
+    this.runMode = runMode;
+  }
+
   setIncrementalFile(path) {
@@ -66,8 +69,7 @@ if (path) {
 
-  _normalizePaths(path, outputPath) {
+  _normalizePaths(path, outputPath, copyOptions = {}) {
     return {
       inputPath: TemplatePath.addLeadingDotSlash(path),
-      outputPath: outputPath
-        ? TemplatePath.stripLeadingDotSlash(outputPath)
-        : true,
+      outputPath: outputPath ? TemplatePath.stripLeadingDotSlash(outputPath) : true,
+      copyOptions,
     };
@@ -78,6 +80,6 @@ }
     let paths = [];
-    let target = this.config.passthroughCopies || {};
-    debug("`addPassthroughCopy` config API paths: %o", target);
-    for (let path in target) {
-      paths.push(this._normalizePaths(path, target[path]));
+    let pathsRaw = this.config.passthroughCopies || {};
+    debug("`addPassthroughCopy` config API paths: %o", pathsRaw);
+    for (let [inputPath, { outputPath, copyOptions }] of Object.entries(pathsRaw)) {
+      paths.push(this._normalizePaths(inputPath, outputPath, copyOptions));
     }
@@ -109,10 +111,14 @@ debug("`addPassthroughCopy` config API normalized paths: %o", paths);
 
+  setFileSystemSearch(fileSystemSearch) {
+    this.fileSystemSearch = fileSystemSearch;
+  }
+
   getTemplatePassthroughForPath(path, isIncremental = false) {
-    let inst = new TemplatePassthrough(
-      path,
-      this.outputDir,
-      this.inputDir,
-      this.config
-    );
+    let inst = new TemplatePassthrough(path, this.outputDir, this.inputDir, this.config);
+
+    inst.setFileSystemSearch(this.fileSystemSearch);
     inst.setIsIncremental(isIncremental);
+    inst.setDryRun(this.isDryRun);
+    inst.setRunMode(this.runMode);
+
     return inst;
@@ -128,5 +134,15 @@ }
 
-    let path = pass.getPath();
-    pass.setDryRun(this.isDryRun);
+    let { inputPath } = pass.getPath();
 
+    // TODO https://github.com/11ty/eleventy/issues/2452
+    // De-dupe both the input and output paired together to avoid the case
+    // where an input/output pair has been added via multiple passthrough methods (glob, file suffix, etc)
+    // Probably start with the `filter` callback in recursive-copy but it only passes relative paths
+    // See the note in TemplatePassthrough.js->write()
+
+    // Also note that `recursive-copy` handles repeated overwrite copy to the same destination just fine.
+    // e.g. `for(let j=0, k=1000; j<k; j++) { copy("coolkid.jpg", "_site/coolkid.jpg"); }`
+
+    // Eventually we’ll want to move all of this to use Node’s fs.cp, which is experimental and only on Node 16+
+
     return pass
@@ -138,12 +154,19 @@ .write()
           if (this.conflictMap[dest]) {
-            throw new TemplatePassthroughManagerCopyError(
-              `Multiple passthrough copy files are trying to write to the same output file (${dest}). ${src} and ${this.conflictMap[dest]}`
-            );
+            if (src !== this.conflictMap[dest]) {
+              throw new TemplatePassthroughManagerCopyError(
+                `Multiple passthrough copy files are trying to write to the same output file (${dest}). ${src} and ${this.conflictMap[dest]}`
+              );
+            } else {
+              // Multiple entries from the same source
+              debug(
+                "A passthrough copy entry (%o) caused the same file (%o) to be copied more than once to the output (%o). This is atomically safe but a waste of build resources.",
+                inputPath,
+                src,
+                dest
+              );
+            }
           }
 
-          debugDev(
-            "Adding %o to passthrough copy conflict map, from %o",
-            dest,
-            src
-          );
+          debugDev("Adding %o to passthrough copy conflict map, from %o", dest, src);
+
           this.conflictMap[dest] = src;
@@ -155,4 +178,4 @@ }
           debug(
-            "Skipped %o (either from --dryrun or --incremental)",
-            path.inputPath
+            "Skipped %o (either from --dryrun or --incremental or for-free passthrough copy)",
+            inputPath
           );
@@ -162,12 +185,16 @@ } else {
             this.count += count;
+            debug("Copied %o (%d files)", inputPath, count || 0);
+          } else {
+            debug("Skipped copying %o (emulated passthrough copy)", inputPath);
           }
-          debug("Copied %o (%d files)", path.inputPath, count || 0);
         }
+
+        return {
+          count,
+          map,
+        };
       })
       .catch(function (e) {
         return Promise.reject(
-          new TemplatePassthroughManagerCopyError(
-            `Having trouble copying '${path.inputPath}'`,
-            e
-          )
+          new TemplatePassthroughManagerCopyError(`Having trouble copying '${inputPath}'`, e)
         );
@@ -203,15 +230,7 @@ });
     if (this.incrementalFile) {
-      let isPassthrough = this.isPassthroughCopyFile(
-        paths,
-        this.incrementalFile
-      );
+      let isPassthrough = this.isPassthroughCopyFile(paths, this.incrementalFile);
 
       if (isPassthrough) {
         if (isPassthrough.outputPath) {
-          return [
-            this._normalizePaths(
-              this.incrementalFile,
-              isPassthrough.outputPath
-            ),
-          ];
+          return [this._normalizePaths(this.incrementalFile, isPassthrough.outputPath)];
         }
@@ -221,11 +240,14 @@
       }
-      return [];
+
+      // Fixes https://github.com/11ty/eleventy/issues/2491
+      if (!checkPassthroughCopyBehavior(this.config, this.runMode)) {
+        return [];
+      }
     }
 
-    let normalizedPaths = [];
-
-    let pathsFromConfigurationFile = this.getConfigPaths();
-    for (let path of pathsFromConfigurationFile) {
-      debug("TemplatePassthrough copying from config: %o", path);
-      normalizedPaths.push(path);
+    let normalizedPaths = this.getConfigPaths();
+    if (debug.enabled) {
+      for (let path of normalizedPaths) {
+        debug("TemplatePassthrough copying from config: %o", path);
+      }
     }
@@ -237,5 +259,7 @@
         let normalizedPath = this._normalizePaths(path);
+
         debug(
           `TemplatePassthrough copying from non-matching file extension: ${normalizedPath.inputPath}`
         );
+
         normalizedPaths.push(normalizedPath);
@@ -248,21 +272,38 @@ }
 
+  // keys: output
+  // values: input
+  getAliasesFromPassthroughResults(result) {
+    let entries = {};
+    for (let entry of result) {
+      for (let src in entry.map) {
+        let dest = TemplatePath.stripLeadingSubPath(entry.map[src], this.outputDir);
+        entries["/" + dest] = src;
+      }
+    }
+    return entries;
+  }
+
   // Performance note: these can actually take a fair bit of time, but aren’t a
   // bottleneck to eleventy. The copies are performed asynchronously and don’t affect eleventy
   // write times in a significant way.
-  async copyAll(paths) {
+  async copyAll(templateExtensionPaths) {
     debug("TemplatePassthrough copy started.");
-    let normalizedPaths = this.getAllNormalizedPaths(paths);
-    let passthroughs = [];
-    for (let path of normalizedPaths) {
+    let normalizedPaths = this.getAllNormalizedPaths(templateExtensionPaths);
+
+    let passthroughs = normalizedPaths.map((path) => {
       // if incrementalFile is set but it isn’t a passthrough copy, normalizedPaths will be an empty array
       let isIncremental = !!this.incrementalFile;
-      passthroughs.push(
-        this.getTemplatePassthroughForPath(path, isIncremental)
-      );
-    }
 
-    return Promise.all(
-      passthroughs.map((pass) => this.copyPassthrough(pass))
-    ).then(() => {
+      return this.getTemplatePassthroughForPath(path, isIncremental);
+    });
+
+    let promises = passthroughs.map((pass) => this.copyPassthrough(pass));
+    return Promise.all(promises).then(async (results) => {
+      let aliases = this.getAliasesFromPassthroughResults(results);
+      await this.config.events.emit("eleventy.passthrough", {
+        map: aliases,
+      });
+
       debug(`TemplatePassthrough copy finished. Current count: ${this.count}`);
+      return results;
     });
@@ -269,0 +310,0 @@ }

src/TemplatePermalink.js

 const path = require("path");
 const normalize = require("normalize-path");
-const { TemplatePath } = require("@11ty/eleventy-utils");
+const { TemplatePath, isPlainObject } = require("@11ty/eleventy-utils");
 
-const isPlainObject = require("./Util/IsPlainObject");
 const serverlessUrlFilter = require("./Filters/ServerlessUrl");
@@ -70,2 +69,10 @@
 
+  setUrlTransforms(transforms) {
+    this._urlTransforms = transforms;
+  }
+
+  get urlTransforms() {
+    return this._urlTransforms || [];
+  }
+
   setServerlessPathData(data) {
@@ -80,3 +87,3 @@ this.serverlessPathData = data;
   _addDefaultLinkFilename(link) {
-    return link + (link.substr(-1) === "/" ? "index.html" : "");
+    return link + (link.slice(-1) === "/" ? "index.html" : "");
   }
@@ -100,2 +107,30 @@
 
+  // Used in url transforms feature
+  static getUrlStem(original) {
+    let subject = original;
+    if (original.endsWith(".html")) {
+      subject = original.slice(0, -1 * ".html".length);
+    }
+    return TemplatePermalink.normalizePathToUrl(subject);
+  }
+
+  static normalizePathToUrl(original) {
+    let compare = original || "";
+
+    let needleHtml = "/index.html";
+    let needleBareTrailingSlash = "/index/";
+    let needleBare = "/index";
+    if (compare.endsWith(needleHtml)) {
+      return compare.slice(0, compare.length - needleHtml.length) + "/";
+    } else if (compare.endsWith(needleBareTrailingSlash)) {
+      return (
+        compare.slice(0, compare.length - needleBareTrailingSlash.length) + "/"
+      );
+    } else if (compare.endsWith(needleBare)) {
+      return compare.slice(0, compare.length - needleBare.length) + "/";
+    }
+
+    return original;
+  }
+
   // This method is used to generate the `page.url` variable.
@@ -138,9 +173,13 @@ // Note that in serverless mode this should still exist to generate the content map
       (transformedLink.charAt(0) !== "/" ? "/" : "") + transformedLink;
-    let needle = "/index.html";
-    if (original === needle) {
-      return "/";
-    } else if (original.substr(-1 * needle.length) === needle) {
-      return original.substr(0, original.length - needle.length) + "/";
+
+    let normalized = TemplatePermalink.normalizePathToUrl(original) || "";
+    for (let transform of this.urlTransforms) {
+      original =
+        transform({
+          url: normalized,
+          urlStem: TemplatePermalink.getUrlStem(original),
+        }) ?? original;
     }
-    return original;
+
+    return TemplatePermalink.normalizePathToUrl(original);
   }
@@ -191,8 +230,9 @@
   ) {
-    let hasDupeFolder = TemplatePermalink._hasDuplicateFolder(
-      dir,
-      filenameNoExt
-    );
     let path;
     if (fileExtension === "html") {
+      let hasDupeFolder = TemplatePermalink._hasDuplicateFolder(
+        dir,
+        filenameNoExt
+      );
+
       path =
@@ -199,0 +239,0 @@ (dir ? dir + "/" : "") +

src/TemplateRender.js

@@ -6,2 +6,3 @@ const { TemplatePath } = require("@11ty/eleventy-utils");
 const EleventyExtensionMap = require("./EleventyExtensionMap");
+const CustomEngine = require("./Engines/Custom.js");
 // const debug = require("debug")("Eleventy:TemplateRender");
@@ -16,5 +17,3 @@
     if (!tmplPath) {
-      throw new Error(
-        `TemplateRender requires a tmplPath argument, instead of ${tmplPath}`
-      );
+      throw new Error(`TemplateRender requires a tmplPath argument, instead of ${tmplPath}`);
     }
@@ -32,6 +31,3 @@ if (!config) {
     this.inputDir = inputDir ? inputDir : this.config.dir.input;
-    this.includesDir = TemplatePath.join(
-      this.inputDir,
-      this.config.dir.includes
-    );
+    this.includesDir = TemplatePath.join(this.inputDir, this.config.dir.includes);
 
@@ -64,2 +60,9 @@ this.parseMarkdownWith = this.config.markdownTemplateEngine;
 
+  getEngineByName(name) {
+    let engine = this.extensionMap.engineManager.getEngine(name, this.getDirs(), this.extensionMap);
+    engine.config = this.config;
+
+    return engine;
+  }
+
   // Runs once per template
@@ -75,9 +78,3 @@ init(engineNameOrPath) {
 
-    this._engine = this.extensionMap.engineManager.getEngine(
-      this._engineName,
-      this.getDirs(),
-      this.extensionMap
-    );
-    this._engine.config = this.config;
-    this._engine.initRequireCache(engineNameOrPath);
+    this._engine = this.getEngineByName(this._engineName);
 
@@ -104,2 +101,6 @@ if (this.useMarkdown === undefined) {
   static parseEngineOverrides(engineName) {
+    if (typeof (engineName || "") !== "string") {
+      throw new Error("Expected String passed to parseEngineOverrides. Received: " + engineName);
+    }
+
     let overlappingEngineWarningCount = 0;
@@ -150,13 +151,21 @@ let engines = [];
   getReadableEnginesList() {
-    return (
-      this.getReadableEnginesListDifferingFromFileExtension() || this.engineName
-    );
+    return this.getReadableEnginesListDifferingFromFileExtension() || this.engineName;
   }
 
   getReadableEnginesListDifferingFromFileExtension() {
-    if (
-      this.engineName === "md" &&
-      this.useMarkdown &&
-      this.parseMarkdownWith
-    ) {
+    let keyFromFilename = this.extensionMap.getKey(this.engineNameOrPath);
+    if (this.engine instanceof CustomEngine) {
+      if (
+        this.engine.entry &&
+        this.engine.entry.name &&
+        keyFromFilename !== this.engine.entry.name
+      ) {
+        return this.engine.entry.name;
+      } else {
+        // We don’t have a name for it so we return nothing so we don’t misreport (per #2386)
+        return;
+      }
+    }
+
+    if (this.engineName === "md" && this.useMarkdown && this.parseMarkdownWith) {
       return this.parseMarkdownWith;
@@ -169,3 +178,2 @@ }
     // templateEngineOverride in play and template language differs from file extension
-    let keyFromFilename = this.extensionMap.getKey(this.engineNameOrPath);
     if (keyFromFilename !== this.engineName) {
@@ -176,2 +184,31 @@ return this.engineName;
 
+  // TODO templateEngineOverride
+  getPreprocessorEngine() {
+    if (this.engineName === "md" && this.parseMarkdownWith) {
+      return this.parseMarkdownWith;
+    }
+    if (this.engineName === "html" && this.parseHtmlWith) {
+      return this.parseHtmlWith;
+    }
+    return this.extensionMap.getKey(this.engineNameOrPath);
+  }
+
+  // We pass in templateEngineOverride here because it isn’t yet applied to templateRender
+  getEnginesList(engineOverride) {
+    if (engineOverride) {
+      let engines = TemplateRender.parseEngineOverrides(engineOverride).reverse();
+      return engines.join(",");
+    }
+
+    if (this.engineName === "md" && this.useMarkdown && this.parseMarkdownWith) {
+      return `${this.parseMarkdownWith},md`;
+    }
+    if (this.engineName === "html" && this.parseHtmlWith) {
+      return this.parseHtmlWith;
+    }
+
+    // templateEngineOverride in play
+    return this.extensionMap.getKey(this.engineNameOrPath);
+  }
+
   setEngineOverride(engineName, bypassMarkdown) {
@@ -248,7 +285,3 @@ let engines = TemplateRender.parseEngineOverrides(engineName);
     } else if (this.engineName === "html") {
-      return this.engine.compile(
-        str,
-        this.engineNameOrPath,
-        this.parseHtmlWith
-      );
+      return this.engine.compile(str, this.engineNameOrPath, this.parseHtmlWith);
     } else {
@@ -255,0 +288,0 @@ return this.engine.compile(str, this.engineNameOrPath);

src/TemplateWriter.js

@@ -10,2 +10,3 @@ const { TemplatePath } = require("@11ty/eleventy-utils");
 const EleventyErrorUtil = require("./EleventyErrorUtil");
+const FileSystemSearch = require("./FileSystemSearch");
 const ConsoleLogger = require("./Util/ConsoleLogger");
@@ -39,3 +40,2 @@
 
-    this.needToSearchForFiles = null;
     this.templateFormats = templateFormats;
@@ -48,2 +48,3 @@
     this.skippedCount = 0;
+    this.isRunInitialBuild = true;
 
@@ -65,6 +66,2 @@ this._templatePathCache = new Map();
   set templateFormats(value) {
-    if (value !== this._templateFormats) {
-      this.needToSearchForFiles = true;
-    }
-
     this._templateFormats = value;
@@ -116,6 +113,3 @@ }
     if (!this._extensionMap) {
-      this._extensionMap = new EleventyExtensionMap(
-        this.templateFormats,
-        this.eleventyConfig
-      );
+      this._extensionMap = new EleventyExtensionMap(this.templateFormats, this.eleventyConfig);
     }
@@ -145,2 +139,3 @@ return this._extensionMap;
       this._eleventyFiles.setInput(this.inputDir, this.input);
+      this._eleventyFiles.setFileSystemSearch(new FileSystemSearch());
       this._eleventyFiles.init();
@@ -153,20 +148,24 @@ }
   async _getAllPaths() {
-    if (!this.allPaths || this.needToSearchForFiles) {
-      this.allPaths = await this.eleventyFiles.getFiles();
-      debug("Found: %o", this.allPaths);
-    }
-    return this.allPaths;
+    // this is now cached upstream by FileSystemSearch
+    return this.eleventyFiles.getFiles();
   }
 
   _isIncrementalFileAPassthroughCopy(paths) {
+    if (!this.incrementalFile) {
+      return false;
+    }
+
     let passthroughManager = this.eleventyFiles.getPassthroughManager();
-    return passthroughManager.isPassthroughCopyFile(
-      paths,
-      this.incrementalFile
-    );
+    return passthroughManager.isPassthroughCopyFile(paths, this.incrementalFile);
   }
 
-  _createTemplate(path, allPaths, to = "fs") {
+  _createTemplate(path, to = "fs") {
     let tmpl = this._templatePathCache.get(path);
-    if (!tmpl) {
+
+    let wasCached = false;
+    if (tmpl) {
+      wasCached = true;
+      // TODO reset other constructor things here like inputDir/outputDir/extensionMap/
+      tmpl.setTemplateData(this.templateData);
+    } else {
       tmpl = new Template(
@@ -180,2 +179,3 @@ path,
       );
+
       tmpl.setOutputFormat(to);
@@ -207,27 +207,10 @@
 
+    tmpl.setDryRun(this.isDryRun);
     tmpl.setIsVerbose(this.isVerbose);
+    tmpl.reset();
 
-    // --incremental only writes files that trigger a build during --watch
-    if (this.incrementalFile) {
-      // incremental file is a passthrough copy (not a template)
-      if (this._isIncrementalFileAPassthroughCopy(allPaths)) {
-        tmpl.setDryRun(true);
-        // Passthrough copy check is above this (order is important)
-      } else if (
-        tmpl.isFileRelevantToThisTemplate(this.incrementalFile, {
-          isFullTemplate: this.eleventyFiles.isFullTemplateFile(
-            allPaths,
-            this.incrementalFile
-          ),
-        })
-      ) {
-        tmpl.setDryRun(this.isDryRun);
-      } else {
-        tmpl.setDryRun(true);
-      }
-    } else {
-      tmpl.setDryRun(this.isDryRun);
-    }
-
-    return tmpl;
+    return {
+      template: tmpl,
+      wasCached,
+    };
   }
@@ -237,9 +220,108 @@
     let promises = [];
+
+    let isIncrementalFileAFullTemplate = this.eleventyFiles.isFullTemplateFile(
+      paths,
+      this.incrementalFile
+    );
+    let isIncrementalFileAPassthroughCopy = this._isIncrementalFileAPassthroughCopy(paths);
+
+    let relevantToDeletions = new Set();
+
+    // Update the data cascade and the global dependency map for the one incremental template before everything else (only full templates)
+    if (isIncrementalFileAFullTemplate && this.incrementalFile) {
+      let path = this.incrementalFile;
+      let { template: tmpl, wasCached } = this._createTemplate(path, to);
+      if (wasCached) {
+        tmpl.resetCaches(); // reset internal caches on the cached template instance
+      }
+
+      // Render overrides are only used when `--ignore-initial` is in play and an initial build is not run
+      if (!this.isRunInitialBuild) {
+        tmpl.setRenderableOverride(undefined); // reset to render enabled
+      }
+
+      let p = this.templateMap.add(tmpl);
+      promises.push(p);
+      await p;
+      debug(`${path} adding to template map.`);
+
+      // establish new relationships for this template
+      relevantToDeletions = this.templateMap.setupDependencyGraphChangesForIncrementalFile(
+        tmpl.inputPath
+      );
+
+      this.templateMap.addToGlobalDependencyGraph();
+    }
+
     for (let path of paths) {
-      if (this.extensionMap.hasEngine(path)) {
-        promises.push(
-          this.templateMap.add(this._createTemplate(path, paths, to))
+      if (!this.extensionMap.hasEngine(path)) {
+        continue;
+      }
+
+      if (isIncrementalFileAPassthroughCopy) {
+        this.skippedCount++;
+        continue;
+      }
+
+      // We already updated the data cascade for this template above
+      if (isIncrementalFileAFullTemplate && this.incrementalFile === path) {
+        continue;
+      }
+
+      let { template: tmpl, wasCached } = this._createTemplate(path, to);
+
+      if (!this.incrementalFile) {
+        // Render overrides are only used when `--ignore-initial` is in play and an initial build is not run
+        if (!this.isRunInitialBuild) {
+          if (wasCached) {
+            tmpl.setRenderableOverride(undefined); // enable render
+          } else {
+            tmpl.setRenderableOverride(false); // disable render
+          }
+        }
+
+        if (wasCached) {
+          tmpl.resetCaches();
+        }
+      } else {
+        let isTemplateRelevantToDeletedCollections = relevantToDeletions.has(
+          TemplatePath.stripLeadingDotSlash(tmpl.inputPath)
         );
+
+        if (
+          isTemplateRelevantToDeletedCollections ||
+          tmpl.isFileRelevantToThisTemplate(this.incrementalFile, {
+            isFullTemplate: isIncrementalFileAFullTemplate,
+          })
+        ) {
+          // Related to the template but not the template (reset the render cache, not the read cache)
+          tmpl.resetCaches({
+            data: true,
+            render: true,
+          });
+
+          // Render overrides are only used when `--ignore-initial` is in play and an initial build is not run
+          if (!this.isRunInitialBuild) {
+            tmpl.setRenderableOverride(undefined); // reset to render enabled
+          }
+        } else {
+          // During incremental we only reset the data cache for non-matching templates, see https://github.com/11ty/eleventy/issues/2710
+          // Keep caches for read/render
+          tmpl.resetCaches({
+            data: true,
+          });
+
+          // Render overrides are only used when `--ignore-initial` is in play and an initial build is not run
+          if (!this.isRunInitialBuild) {
+            tmpl.setRenderableOverride(false); // false to disable render
+          }
+
+          tmpl.setDryRunViaIncremental();
+          this.skippedCount++;
+        }
       }
-      debug(`${path} begun adding to map.`);
+
+      // This fetches the data cascade for this template, which we want to avoid if not applicable to incremental
+      promises.push(this.templateMap.add(tmpl));
+      debug(`${path} adding to template map.`);
     }
@@ -254,2 +336,6 @@
     await this._addToTemplateMap(paths, to);
+
+    // write new template relationships to the global dependency graph for next time
+    this.templateMap.addToGlobalDependencyGraph();
+
     await this.templateMap.cache();
@@ -265,3 +351,2 @@
     return tmpl.generateMapEntry(mapEntry, to).then((pages) => {
-      this.skippedCount += tmpl.getSkippedCount();
       this.writeCount += tmpl.getWriteCount();
@@ -272,11 +357,9 @@ return pages;
 
-  async writePassthroughCopy(paths) {
+  async writePassthroughCopy(templateExtensionPaths) {
     let passthroughManager = this.eleventyFiles.getPassthroughManager();
     passthroughManager.setIncrementalFile(this.incrementalFile);
 
-    return passthroughManager.copyAll(paths).catch((e) => {
+    return passthroughManager.copyAll(templateExtensionPaths).catch((e) => {
       this.errorHandler.warn(e, "Error with passthrough copy");
-      return Promise.reject(
-        new EleventyPassthroughCopyError("Having trouble copying", e)
-      );
+      return Promise.reject(new EleventyPassthroughCopyError("Having trouble copying", e));
     });
@@ -305,3 +388,3 @@ }
               new EleventyTemplateError(
-                `Having trouble writing template: "${mapEntry.outputPath}"`,
+                `Having trouble writing to "${mapEntry.outputPath}" from "${mapEntry.inputPath}"`,
                 e
@@ -320,3 +403,3 @@ )
             new EleventyTemplateError(
-              `Having trouble writing template (second pass): "${mapEntry.outputPath}"`,
+              `Having trouble writing to (second pass) "${mapEntry.outputPath}" from "${mapEntry.inputPath}"`,
               e
@@ -336,2 +419,3 @@ )
 
+    // The ordering here is important to destructuring in Eleventy->_watch
     promises.push(this.writePassthroughCopy(paths));
@@ -374,2 +458,8 @@
 
+  setRunInitialBuild(runInitialBuild) {
+    this.isRunInitialBuild = runInitialBuild;
+  }
+  setIncrementalBuild(isIncremental) {
+    this.isIncremental = isIncremental;
+  }
   setIncrementalFile(incrementalFile) {
@@ -386,6 +476,2 @@ this.incrementalFile = incrementalFile;
 
-  getSkippedCopyCount() {
-    return this.eleventyFiles.getPassthroughManager().getSkippedCount();
-  }
-
   getWriteCount() {
@@ -398,4 +484,8 @@ return this.writeCount;
   }
+
+  get caches() {
+    return ["_templatePathCache"];
+  }
 }
 
 module.exports = TemplateWriter;

src/UserConfig.js

 const chalk = require("kleur");
-const semver = require("semver");
 const { DateTime } = require("luxon");
+
 const EventEmitter = require("./Util/AsyncEventEmitter");
+const EleventyCompatibility = require("./Util/Compatibility");
 const EleventyBaseError = require("./EleventyBaseError");
 const BenchmarkManager = require("./BenchmarkManager");
 const merge = require("./Util/Merge");
+
 const debug = require("debug")("Eleventy:UserConfig");
-const pkg = require("../package.json");
 
 class UserConfigError extends EleventyBaseError {}
 
+const ComparisonAsyncFunction = (async () => {}).constructor;
+
 // API to expose configuration options in config file
@@ -38,3 +41,5 @@ class UserConfig {
     this.liquidPairedShortcodes = {};
+
     this.nunjucksEnvironmentOptions = {};
+    this.nunjucksPrecompiledTemplates = {};
     this.nunjucksFilters = {};
@@ -48,5 +53,7 @@ this.nunjucksAsyncFilters = {};
     this.nunjucksAsyncPairedShortcodes = {};
+
     this.handlebarsHelpers = {};
     this.handlebarsShortcodes = {};
     this.handlebarsPairedShortcodes = {};
+
     this.javascriptFunctions = {};
@@ -60,2 +67,4 @@ this.pugOptions = {};
     this.layoutAliases = {};
+    this.layoutResolution = true; // extension-less layout files
+
     this.linters = {};
@@ -68,5 +77,9 @@ this.transforms = {};
     this.useGitIgnore = true;
-    this.ignores = new Set();
-    this.ignores.add("node_modules/**");
 
+    let defaultIgnores = new Set();
+    defaultIgnores.add("**/node_modules/**");
+    defaultIgnores.add(".git/**");
+    this.ignores = new Set(defaultIgnores);
+    this.watchIgnores = new Set(defaultIgnores);
+
     this.dataDeepMerge = true;
@@ -76,3 +89,3 @@ this.extensionMap = new Set();
     this.additionalWatchTargets = [];
-    this.browserSyncConfig = {};
+    this.serverOptions = {};
     this.globalData = {};
@@ -92,13 +105,18 @@ this.chokidarConfig = {};
     this.dataFilterSelectors = new Set();
+
+    this.libraryAmendments = {};
+    this.serverPassthroughCopyBehavior = "copy"; // or "passthrough"
+    this.urlTransforms = [];
+
+    // Defaults in `defaultConfig.js`
+    this.dataFileSuffixesOverride = false;
+    this.dataFileDirBaseNameOverride = false;
   }
 
-  versionCheck(expected) {
-    if (
-      !semver.satisfies(pkg.version, expected, {
-        includePrerelease: true,
-      })
-    ) {
-      throw new UserConfigError(
-        `This project requires the Eleventy version to match '${expected}' but found ${pkg.version}. Use \`npm update @11ty/eleventy -g\` to upgrade the eleventy global or \`npm update @11ty/eleventy --save\` to upgrade your local project version.`
-      );
+  // compatibleRange is optional in 2.0.0-beta.2
+  versionCheck(compatibleRange) {
+    let compat = new EleventyCompatibility(compatibleRange);
+
+    if (!compat.isCompatible()) {
+      throw new UserConfigError(compat.getErrorMessage());
     }
@@ -140,13 +158,5 @@ }
     if (this.liquidTags[name]) {
-      debug(
-        chalk.yellow(
-          "Warning, overwriting a Liquid tag with `addLiquidTag(%o)`"
-        ),
-        name
-      );
+      debug(chalk.yellow("Warning, overwriting a Liquid tag with `addLiquidTag(%o)`"), name);
     }
-    this.liquidTags[name] = this.benchmarks.config.add(
-      `"${name}" Liquid Custom Tag`,
-      tagFn
-    );
+    this.liquidTags[name] = this.benchmarks.config.add(`"${name}" Liquid Custom Tag`, tagFn);
   }
@@ -158,14 +168,6 @@
     if (this.liquidFilters[name]) {
-      debug(
-        chalk.yellow(
-          "Warning, overwriting a Liquid filter with `addLiquidFilter(%o)`"
-        ),
-        name
-      );
+      debug(chalk.yellow("Warning, overwriting a Liquid filter with `addLiquidFilter(%o)`"), name);
     }
 
-    this.liquidFilters[name] = this.benchmarks.config.add(
-      `"${name}" Liquid Filter`,
-      callback
-    );
+    this.liquidFilters[name] = this.benchmarks.config.add(`"${name}" Liquid Filter`, callback);
   }
@@ -178,5 +180,3 @@
       debug(
-        chalk.yellow(
-          "Warning, overwriting a Nunjucks filter with `addNunjucksAsyncFilter(%o)`"
-        ),
+        chalk.yellow("Warning, overwriting a Nunjucks filter with `addNunjucksAsyncFilter(%o)`"),
         name
@@ -202,5 +202,3 @@ );
         debug(
-          chalk.yellow(
-            "Warning, overwriting a Nunjucks filter with `addNunjucksFilter(%o)`"
-          ),
+          chalk.yellow("Warning, overwriting a Nunjucks filter with `addNunjucksFilter(%o)`"),
           name
@@ -222,5 +220,3 @@ );
       debug(
-        chalk.yellow(
-          "Warning, overwriting a Handlebars helper with `addHandlebarsHelper(%o)`."
-        ),
+        chalk.yellow("Warning, overwriting a Handlebars helper with `addHandlebarsHelper(%o)`."),
         name
@@ -237,2 +233,8 @@ );
   addFilter(name, callback) {
+    // This method *requires* `async function` and will not work with `function` that returns a promise
+    if (callback instanceof ComparisonAsyncFunction) {
+      this.addAsyncFilter(name, callback);
+      return;
+    }
+
     debug("Adding universal filter %o", this.getNamespacedName(name));
@@ -242,5 +244,14 @@
     this.addLiquidFilter(name, callback);
-    this.addNunjucksFilter(name, callback);
     this.addJavaScriptFunction(name, callback);
 
+    this.addNunjucksFilter(name, function (...args) {
+      let ret = callback.call(this, ...args);
+      if (ret instanceof Promise) {
+        throw new Error(
+          `Nunjucks *is* async-friendly with \`addFilter("${name}", async function() {})\` but you need to supply an \`async function\`. You returned a promise from \`addFilter("${name}", function() {})\`. Alternatively, use the \`addAsyncFilter("${name}")\` configuration API method.`
+        );
+      }
+      return ret;
+    });
+
     // TODO remove Handlebars helpers in Universal Filters. Use shortcodes instead (the Handlebars template syntax is the same).
@@ -250,2 +261,18 @@ this.addHandlebarsHelper(name, callback);
 
+  // Liquid, Nunjucks, and JS only
+  addAsyncFilter(name, callback) {
+    debug("Adding universal async filter %o", this.getNamespacedName(name));
+
+    // namespacing happens downstream
+    this.addLiquidFilter(name, callback);
+    this.addJavaScriptFunction(name, callback);
+    this.addNunjucksAsyncFilter(name, async function (...args) {
+      let cb = args.pop();
+      let ret = await callback.call(this, ...args);
+      cb(null, ret);
+    });
+
+    // Note: no handlebars
+  }
+
   getFilter(name) {
@@ -270,14 +297,6 @@ return (
     if (this.nunjucksTags[name]) {
-      debug(
-        chalk.yellow(
-          "Warning, overwriting a Nunjucks tag with `addNunjucksTag(%o)`"
-        ),
-        name
-      );
+      debug(chalk.yellow("Warning, overwriting a Nunjucks tag with `addNunjucksTag(%o)`"), name);
     }
 
-    this.nunjucksTags[name] = this.benchmarks.config.add(
-      `"${name}" Nunjucks Custom Tag`,
-      tagFn
-    );
+    this.nunjucksTags[name] = this.benchmarks.config.add(`"${name}" Nunjucks Custom Tag`, tagFn);
   }
@@ -296,5 +315,3 @@
       debug(
-        chalk.yellow(
-          "Warning, overwriting a Nunjucks global with `addNunjucksGlobal(%o)`"
-        ),
+        chalk.yellow("Warning, overwriting a Nunjucks global with `addNunjucksGlobal(%o)`"),
         name
@@ -317,3 +334,3 @@ );
 
-    this.transforms[name] = callback;
+    this.transforms[name] = this.benchmarks.config.add(`"${name}" Transform`, callback);
   }
@@ -324,3 +341,3 @@
 
-    this.linters[name] = callback;
+    this.linters[name] = this.benchmarks.config.add(`"${name}" Linter`, callback);
   }
@@ -332,2 +349,11 @@
 
+  setLayoutResolution(resolution) {
+    this.layoutResolution = !!resolution;
+  }
+
+  // compat
+  enableLayoutResolution() {
+    this.layoutResolution = true;
+  }
+
   // get config defined collections
@@ -366,6 +392,3 @@ getCollections() {
       return plugin.name;
-    } else if (
-      plugin.configFunction &&
-      typeof plugin.configFunction === "function"
-    ) {
+    } else if (plugin.configFunction && typeof plugin.configFunction === "function") {
       return plugin.configFunction.name;
@@ -378,5 +401,3 @@ }
     debug(`Adding ${name || "anonymous"} plugin`);
-    let pluginBenchmark = this.benchmarks.aggregate.get(
-      "Configuration addPlugin"
-    );
+    let pluginBenchmark = this.benchmarks.aggregate.get("Configuration addPlugin");
     if (typeof plugin === "function") {
@@ -426,10 +447,15 @@ pluginBenchmark.before();
    * be copied. OR an object where the key is the input glob and the property is the output directory
+   * @param {object} copyOptions options for recursive-copy.
+   * see https://www.npmjs.com/package/recursive-copy#arguments
+   * default options are defined in TemplatePassthrough copyOptionsDefault
    * @returns {any} a reference to the `EleventyConfig` object.
    * @memberof EleventyConfig
    */
-  addPassthroughCopy(fileOrDir) {
+  addPassthroughCopy(fileOrDir, copyOptions = {}) {
     if (typeof fileOrDir === "string") {
-      this.passthroughCopies[fileOrDir] = true;
+      this.passthroughCopies[fileOrDir] = { outputPath: true, copyOptions };
     } else {
-      Object.assign(this.passthroughCopies, fileOrDir);
+      for (let [inputPath, outputPath] of Object.entries(fileOrDir)) {
+        this.passthroughCopies[inputPath] = { outputPath, copyOptions };
+      }
     }
@@ -440,9 +466,22 @@
 
-  _normalizeTemplateFormats(templateFormats) {
-    if (typeof templateFormats === "string") {
-      templateFormats = templateFormats
-        .split(",")
-        .map((format) => format.trim());
+  _normalizeTemplateFormats(templateFormats, existingValues) {
+    // setTemplateFormats(null) should return null
+    if (templateFormats === null || templateFormats === undefined) {
+      return null;
     }
-    return templateFormats;
+
+    let set = new Set();
+    if (Array.isArray(templateFormats)) {
+      set = new Set(templateFormats.map((format) => format.trim()));
+    } else if (typeof templateFormats === "string") {
+      for (let format of templateFormats.split(",")) {
+        set.add(format.trim());
+      }
+    }
+
+    for (let format of existingValues || []) {
+      set.add(format);
+    }
+
+    return Array.from(set);
   }
@@ -456,7 +495,5 @@
   addTemplateFormats(templateFormats) {
-    if (!this.templateFormatsAdded) {
-      this.templateFormatsAdded = [];
-    }
-    this.templateFormatsAdded = this.templateFormatsAdded.concat(
-      this._normalizeTemplateFormats(templateFormats)
+    this.templateFormatsAdded = this._normalizeTemplateFormats(
+      templateFormats,
+      this.templateFormatsAdded
     );
@@ -471,6 +508,3 @@ }
       );
-    } else if (
-      engineName === "njk" &&
-      Object.keys(this.nunjucksEnvironmentOptions).length
-    ) {
+    } else if (engineName === "njk" && Object.keys(this.nunjucksEnvironmentOptions).length) {
       debug(
@@ -484,2 +518,12 @@ "WARNING: using `eleventyConfig.setLibrary` will override any configuration set using `.setNunjucksEnvironmentOptions` via the config API. You’ll need to pass these options to the library yourself."
 
+  /* These callbacks run on both libraryOverrides and default library instances */
+  amendLibrary(engineName, callback) {
+    let name = engineName.toLowerCase();
+    if (!this.libraryAmendments[name]) {
+      this.libraryAmendments[name] = [];
+    }
+
+    this.libraryAmendments[name].push(callback);
+  }
+
   setPugOptions(options) {
@@ -497,2 +541,6 @@ this.pugOptions = options;
 
+  setNunjucksPrecompiledTemplates(templates) {
+    this.nunjucksPrecompiledTemplates = templates;
+  }
+
   setEjsOptions(options) {
@@ -511,16 +559,26 @@ this.ejsOptions = options;
   addShortcode(name, callback) {
+    // This method *requires* `async function` and will not work with `function` that returns a promise
+    if (callback instanceof ComparisonAsyncFunction) {
+      this.addAsyncShortcode(name, callback); // Note: no handlebars
+      return;
+    }
+
     debug("Adding universal shortcode %o", this.getNamespacedName(name));
+    this.addLiquidShortcode(name, callback);
+    this.addJavaScriptFunction(name, callback);
     this.addNunjucksShortcode(name, callback);
-    this.addLiquidShortcode(name, callback);
+
+    // Note: Handlebars is sync-only
     this.addHandlebarsShortcode(name, callback);
-    this.addJavaScriptFunction(name, callback);
   }
 
-  // Undocumented method as a mitigation to reduce risk of #498
   addAsyncShortcode(name, callback) {
     debug("Adding universal async shortcode %o", this.getNamespacedName(name));
+
+    // Related: #498
     this.addNunjucksAsyncShortcode(name, callback);
     this.addLiquidShortcode(name, callback);
     this.addJavaScriptFunction(name, callback);
-    // not supported in Handlebars
+
+    // Note: Handlebars is not async-friendly
   }
@@ -554,5 +612,3 @@
         debug(
-          chalk.yellow(
-            "Warning, overwriting a Nunjucks Shortcode with `addNunjucksShortcode(%o)`"
-          ),
+          chalk.yellow("Warning, overwriting a Nunjucks Shortcode with `addNunjucksShortcode(%o)`"),
           name
@@ -574,5 +630,3 @@ );
       debug(
-        chalk.yellow(
-          "Warning, overwriting a Liquid Shortcode with `addLiquidShortcode(%o)`"
-        ),
+        chalk.yellow("Warning, overwriting a Liquid Shortcode with `addLiquidShortcode(%o)`"),
         name
@@ -607,7 +661,15 @@ );
   addPairedShortcode(name, callback) {
+    // This method *requires* `async function` and will not work with `function` that returns a promise
+    if (callback instanceof ComparisonAsyncFunction) {
+      this.addPairedAsyncShortcode(name, callback); // Note: no handlebars
+      return;
+    }
+
     debug("Adding universal paired shortcode %o", this.getNamespacedName(name));
     this.addPairedNunjucksShortcode(name, callback);
     this.addPairedLiquidShortcode(name, callback);
+    this.addJavaScriptFunction(name, callback);
+
+    // Note: Handlebars is sync-only
     this.addPairedHandlebarsShortcode(name, callback);
-    this.addJavaScriptFunction(name, callback);
   }
@@ -617,10 +679,7 @@
   addPairedAsyncShortcode(name, callback) {
-    debug(
-      "Adding universal async paired shortcode %o",
-      this.getNamespacedName(name)
-    );
+    debug("Adding universal async paired shortcode %o", this.getNamespacedName(name));
     this.addPairedNunjucksAsyncShortcode(name, callback);
     this.addPairedLiquidShortcode(name, callback);
     this.addJavaScriptFunction(name, callback);
-    // not supported in Handlebars
+    // Note: Handlebars is sync-only
   }
@@ -739,10 +798,17 @@
 
-  setBrowserSyncConfig(options = {}, mergeOptions = true) {
-    if (mergeOptions) {
-      this.browserSyncConfig = merge(this.browserSyncConfig, options);
+  setServerOptions(options = {}, override = false) {
+    if (override) {
+      this.serverOptions = options;
     } else {
-      this.browserSyncConfig = options;
+      this.serverOptions = merge(this.serverOptions, options);
     }
   }
 
+  setBrowserSyncConfig() {
+    this._attemptedBrowserSyncUse = true;
+    debug(
+      "The `setBrowserSyncConfig` method was removed in Eleventy 2.0.0. Use `setServerOptions` with the new Eleventy development server or the `@11ty/eleventy-browser-sync` plugin moving forward."
+    );
+  }
+
   setChokidarConfig(options = {}) {
@@ -765,15 +831,46 @@ this.chokidarConfig = options;
   addExtension(fileExtension, options = {}) {
-    this.extensionMap.add(
-      Object.assign(
-        {
-          key: fileExtension,
-          extension: fileExtension,
-        },
-        options
-      )
-    );
+    let extensions;
+    // Array support added in 2.0.0-canary.19
+    if (Array.isArray(fileExtension)) {
+      extensions = fileExtension;
+    } else {
+      // single string
+      extensions = [fileExtension];
+    }
+
+    for (let extension of extensions) {
+      this.extensionMap.add(
+        Object.assign(
+          {
+            key: extension,
+            extension: extension,
+          },
+          options
+        )
+      );
+    }
   }
 
-  addDataExtension(formatExtension, formatParser) {
-    this.dataExtensions.set(formatExtension, formatParser);
+  addDataExtension(extensionList, parser) {
+    let options = {};
+    // second argument is an object with a `parser` callback
+    if (typeof parser !== "function") {
+      if (!("parser" in parser)) {
+        throw new Error(
+          "Expected `parser` property in second argument object to `eleventyConfig.addDataExtension`"
+        );
+      }
+
+      options = parser;
+      parser = options.parser;
+    }
+
+    let extensions = extensionList.split(",").map((s) => s.trim());
+    for (let extension of extensions) {
+      this.dataExtensions.set(extension, {
+        extension,
+        parser,
+        options,
+      });
+    }
   }
@@ -789,4 +886,22 @@
 
+  // "passthrough" is the default, no other value is explicitly required in code
+  // but opt-out via "copy" is suggested
+  setServerPassthroughCopyBehavior(behavior) {
+    this.serverPassthroughCopyBehavior = behavior;
+  }
+
+  addUrlTransform(callback) {
+    this.urlTransforms.push(callback);
+  }
+
+  setDataFileSuffixes(suffixArray) {
+    this.dataFileSuffixesOverride = suffixArray;
+  }
+
+  setDataFileBaseName(baseName) {
+    this.dataFileDirBaseNameOverride = baseName;
+  }
+
   getMergingConfigObject() {
-    return {
+    let obj = {
       templateFormats: this.templateFormats,
@@ -799,2 +914,3 @@ templateFormatsAdded: this.templateFormatsAdded,
       layoutAliases: this.layoutAliases,
+      layoutResolution: this.layoutResolution,
       passthroughCopies: this.passthroughCopies,
@@ -807,2 +923,3 @@ liquidOptions: this.liquidOptions,
       nunjucksEnvironmentOptions: this.nunjucksEnvironmentOptions,
+      nunjucksPrecompiledTemplates: this.nunjucksPrecompiledTemplates,
       nunjucksFilters: this.nunjucksFilters,
@@ -827,6 +944,7 @@ nunjucksAsyncFilters: this.nunjucksAsyncFilters,
       ignores: this.ignores,
+      watchIgnores: this.watchIgnores,
       dataDeepMerge: this.dataDeepMerge,
       watchJavaScriptDependencies: this.watchJavaScriptDependencies,
       additionalWatchTargets: this.additionalWatchTargets,
-      browserSyncConfig: this.browserSyncConfig,
+      serverOptions: this.serverOptions,
       chokidarConfig: this.chokidarConfig,
@@ -844,3 +962,17 @@ watchThrottleWaitTime: this.watchThrottleWaitTime,
       dataFilterSelectors: this.dataFilterSelectors,
+      libraryAmendments: this.libraryAmendments,
+      serverPassthroughCopyBehavior: this.serverPassthroughCopyBehavior,
+      urlTransforms: this.urlTransforms,
     };
+
+    if (Array.isArray(this.dataFileSuffixesOverride)) {
+      // no upstream merging of this array, so we add the override: prefix
+      obj["override:dataFileSuffixes"] = this.dataFileSuffixesOverride;
+    }
+
+    if (this.dataFileDirBaseNameOverride) {
+      obj.dataFileDirBaseNameOverride = this.dataFileDirBaseNameOverride;
+    }
+
+    return obj;
   }
@@ -847,0 +979,0 @@ }

src/Util/AsyncEventEmitter.js

@@ -21,4 +21,31 @@ const EventEmitter = require("events");
   }
+
+  /**
+   * @param {string} type - The event name to emit.
+   * @param {*[]} args - Additional lazy-executed function arguments that get passed to listeners.
+   * @returns {Promise<*[]>} - Promise resolves once all listeners were invoked
+   */
+  async emitLazy(type, ...args) {
+    let listeners = this.listeners(type);
+    if (listeners.length === 0) {
+      return [];
+    }
+
+    let argsMap = [];
+    for (let arg of args) {
+      if (typeof arg === "function") {
+        let r = arg();
+        if (r instanceof Promise) {
+          r = await r;
+        }
+        argsMap.push(r);
+      } else {
+        argsMap.push(arg);
+      }
+    }
+
+    return this.emit.call(this, type, ...argsMap);
+  }
 }
 
 module.exports = AsyncEventEmitter;

src/Util/ConsoleLogger.js

@@ -51,2 +51,7 @@ const chalk = require("kleur");
   /** @param {string} msg */
+  info(msg) {
+    this.message(msg, "warn", "blue");
+  }
+
+  /** @param {string} msg */
   warn(msg) {
@@ -56,3 +61,2 @@ this.message(msg, "warn", "yellow");
 
-  // Is this used?
   /** @param {string} msg */
@@ -59,0 +63,0 @@ error(msg) {

src/Util/DeleteRequireCache.js

 const path = require("path");
+const { TemplatePath } = require("@11ty/eleventy-utils");
+const debug = require("debug")("Eleventy:DeleteRequireCache");
 
@@ -6,7 +8,18 @@ /**
  * The keys of the nodejs require cache are file paths based on the current operating system.
- * @param {string} absoluteModulePath An absolute POSIX path to the module.
+ * @param {string} absolutePath An absolute POSIX path to the file.
  */
-module.exports = function deleteRequireCache(absoluteModulePath) {
-  const normalizedPath = path.normalize(absoluteModulePath);
+function deleteRequireCacheAbsolute(absolutePath) {
+  const normalizedPath = path.normalize(absolutePath);
+  debug("Deleting %o from `require` cache.", normalizedPath);
   delete require.cache[normalizedPath];
-};
+}
+
+function deleteRequireCache(localPath) {
+  let absolutePath = TemplatePath.absolutePath(localPath);
+  deleteRequireCacheAbsolute(absolutePath);
+}
+
+module.exports = deleteRequireCache; // will transform local paths to absolute
+
+// Export for testing only
+module.exports.deleteRequireCacheAbsolute = deleteRequireCacheAbsolute;

src/Util/Merge.js

@@ -1,10 +0,14 @@
-const isPlainObject = require("./IsPlainObject");
+const { isPlainObject } = require("@11ty/eleventy-utils");
 const OVERRIDE_PREFIX = "override:";
 
-function getMergedItem(target, source, parentKey) {
-  // if key is prefixed with OVERRIDE_PREFIX, it just keeps the new source value (no merging)
-  if (parentKey && parentKey.indexOf(OVERRIDE_PREFIX) === 0) {
-    return source;
+function cleanKey(key, prefix) {
+  if (prefix && key.startsWith(prefix)) {
+    return key.slice(prefix.length);
   }
+  return key;
+}
 
+function getMergedItem(target, source, prefixes = {}) {
+  let { override } = prefixes;
+
   // deep copy objects to avoid sharing and to effect key renaming
@@ -19,22 +23,32 @@ if (!target && isPlainObject(source)) {
     if (isPlainObject(source)) {
-      for (var key in source) {
-        let newKey = key;
-        if (key.indexOf(OVERRIDE_PREFIX) === 0) {
-          newKey = key.substr(OVERRIDE_PREFIX.length);
-        }
-        target[newKey] = getMergedItem(target[key], source[key], newKey);
+      for (let key in source) {
+        let overrideKey = cleanKey(key, override);
+
+        target[overrideKey] = getMergedItem(target[key], source[key], prefixes);
       }
     }
     return target;
-  } else {
-    // number, string, class instance, etc
-    return source;
   }
+  // number, string, class instance, etc
+  return source;
 }
+
+// The same as Merge but without override prefixes
+function DeepCopy(targetObject, ...sources) {
+  for (let source of sources) {
+    if (!source) {
+      continue;
+    }
+
+    targetObject = getMergedItem(targetObject, source);
+  }
+  return targetObject;
+}
+
 function Merge(target, ...sources) {
   // Remove override prefixes from root target.
   if (isPlainObject(target)) {
-    for (var key in target) {
+    for (let key in target) {
       if (key.indexOf(OVERRIDE_PREFIX) === 0) {
-        target[key.substr(OVERRIDE_PREFIX.length)] = target[key];
+        target[key.slice(OVERRIDE_PREFIX.length)] = target[key];
         delete target[key];
@@ -45,7 +59,9 @@ }
 
-  for (var source of sources) {
+  for (let source of sources) {
     if (!source) {
       continue;
     }
-    target = getMergedItem(target, source);
+    target = getMergedItem(target, source, {
+      override: OVERRIDE_PREFIX,
+    });
   }
@@ -57,1 +73,2 @@
 module.exports = Merge;
+module.exports.DeepCopy = DeepCopy;

src/Util/Sortable.js

@@ -56,7 +56,7 @@ class Sortable {
 
-  setSortDescending() {
-    this.isSortAscending = false;
+  setSortDescending(isDescending = true) {
+    this.isSortAscending = !isDescending;
   }
 
-  setSortAscending(isAscending) {
+  setSortAscending(isAscending = true) {
     this.isSortAscending = isAscending;
@@ -63,0 +63,0 @@ }

New alerts

Dynamic require

Supply chain risk

Dynamic require can indicate the package is performing dangerous or unsafe dynamic code execution.

Found 1 instance in 1 package

Environment variable access

Supply chain risk

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

Found 1 instance in 1 package

Fixed alerts

Dynamic require

Supply chain risk

Dynamic require can indicate the package is performing dangerous or unsafe dynamic code execution.

Found 1 instance in 1 package

Environment variable access

Supply chain risk

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

476110

increased by30.13%

Number of package files

105

increased by32.91%

Lines of code

13679

increased by23.5%

Worsened metrics

Dependency count

40

increased by17.65%

Number of low supply chain risk alerts

40

increased by14.29%

Dependency changes

• + Added@11ty/eleventy-dev-server@^1.0.3

• + Addedbcp-47-normalize@^1.1.1

• + Addediso-639-1@^2.1.15

• + Addedlodash.chunk@^4.2.0

• + Addedlodash.get@^4.4.2

• + Addedlodash.set@^4.3.2

• + Addedmicromatch@^4.0.5

• + Addedposthtml@^0.16.6

• + Addedposthtml-urls@^1.0.0

• + Added@11ty/eleventy-dev-server@1.0.4(transitive)

• + Addedany-promise@0.1.0(transitive)

• + Addedbcp-47@1.0.8(transitive)

• + Addedbcp-47-match@1.0.3(transitive)

• + Addedbcp-47-normalize@1.1.1(transitive)

• + Addeddom-serializer@1.4.1(transitive)

• + Addeddomelementtype@2.3.0(transitive)

• + Addeddomhandler@4.3.1(transitive)

• + Addeddomutils@2.8.0(transitive)

• + Addedentities@2.2.03.0.1(transitive)

• + Addedfinalhandler@1.2.0(transitive)

• + Addedhtmlparser2@7.2.0(transitive)

• + Addedhttp-equiv-refresh@1.0.0(transitive)

• + Addedis-alphabetical@1.0.4(transitive)

• + Addedis-alphanumerical@1.0.4(transitive)

• + Addedis-decimal@1.0.4(transitive)

• + Addedis-json@2.0.1(transitive)

• + Addediso-639-1@2.1.15(transitive)

• + Addedlinkify-it@4.0.1(transitive)

• + Addedliquidjs@10.14.0(transitive)

• + Addedlist-to-array@1.1.0(transitive)

• + Addedlodash.chunk@4.2.0(transitive)

• + Addedlodash.get@4.4.2(transitive)

• + Addedlodash.set@4.3.2(transitive)

• + Addedluxon@3.4.4(transitive)

• + Addedmarkdown-it@13.0.2(transitive)

• + Addedmime@3.0.0(transitive)

• + Addedminipass@3.3.6(transitive)

• + Addedmorphdom@2.7.3(transitive)

• + Addedon-finished@2.4.1(transitive)

• + Addedparse-srcset@1.0.2(transitive)

• + Addedposthtml@0.16.6(transitive)

• + Addedposthtml-parser@0.11.0(transitive)

• + Addedposthtml-render@3.0.0(transitive)

• + Addedposthtml-urls@1.0.0(transitive)

• + Addedpromise-each@2.2.0(transitive)

• + Addedssri@8.0.1(transitive)

• + Addedws@8.18.0(transitive)

• + Addedyallist@4.0.0(transitive)

• - Removedbrowser-sync@^2.27.10

• - Removedlodash@^4.17.21

• - Removedpretty@^2.0.0

• - Removed@isaacs/cliui@8.0.2(transitive)

• - Removed@one-ini/wasm@0.1.1(transitive)

• - Removed@pkgjs/parseargs@0.11.0(transitive)

• - [e-mail]/component-emitter@3.1.2(transitive)

• - Removed@types/cookie@0.4.1(transitive)

• - Removed@types/cors@2.8.17(transitive)

• - Removed@types/node@20.14.10(transitive)

• - Removedabbrev@2.0.0(transitive)

• - Removedaccepts@1.3.8(transitive)

• - Removedansi-regex@5.0.16.0.1(transitive)

• - Removedansi-styles@6.2.1(transitive)

• - Removedasync@2.6.4(transitive)

• - Removedasync-each-series@0.1.1(transitive)

• - Removedaxios@0.21.4(transitive)

• - Removedbase64id@2.0.0(transitive)

• - Removedbatch@0.6.1(transitive)

• - Removedbrowser-sync@2.29.3(transitive)

• - Removedbrowser-sync-client@2.29.3(transitive)

• - Removedbrowser-sync-ui@2.29.3(transitive)

• - Removedbs-recipes@1.3.4(transitive)

• - Removedbytes@3.1.2(transitive)

• - Removedcliui@7.0.48.0.1(transitive)

• - Removedcommander@2.20.3(transitive)

• - Removedcondense-newlines@0.2.1(transitive)

• - Removedconfig-chain@1.1.13(transitive)

• - Removedconnect@3.6.6(transitive)

• - Removedconnect-history-api-fallback@1.6.0(transitive)

• - Removedcookie@0.4.2(transitive)

• - Removedcors@2.8.5(transitive)

• - Removeddebug@4.3.2(transitive)

• - Removeddepd@1.1.22.0.0(transitive)

• - Removeddestroy@1.0.4(transitive)

• - Removedeastasianwidth@0.2.0(transitive)

• - Removedeasy-extender@2.3.4(transitive)

• - Removedeazy-logger@4.0.1(transitive)

• - Removededitorconfig@1.0.4(transitive)

• - Removedemoji-regex@8.0.09.2.2(transitive)

• - Removedengine.io@6.5.5(transitive)

• - Removedengine.io-client@6.5.4(transitive)

• - Removedengine.io-parser@5.2.2(transitive)

• - Removedentities@2.1.0(transitive)

• - Removedescalade@3.1.2(transitive)

• - Removedetag@1.8.1(transitive)

• - Removedeventemitter3@4.0.7(transitive)

• - Removedfinalhandler@1.1.0(transitive)

• - Removedfollow-redirects@1.15.6(transitive)

• - Removedforeground-child@3.2.1(transitive)

• - Removedfresh@0.5.2(transitive)

• - Removedfs-extra@3.0.1(transitive)

• - Removedget-caller-file@2.0.5(transitive)

• - Removedglob@10.4.2(transitive)

• - Removedhttp-errors@1.6.32.0.0(transitive)

• - Removedhttp-proxy@1.18.1(transitive)

• - Removediconv-lite@0.4.24(transitive)

• - Removedimmutable@3.8.2(transitive)

• - Removedinherits@2.0.3(transitive)

• - Removedini@1.3.8(transitive)

• - Removedis-buffer@1.1.6(transitive)

• - Removedis-fullwidth-code-point@3.0.0(transitive)

• - Removedis-number-like@1.0.8(transitive)

• - Removedis-whitespace@0.3.0(transitive)

• - Removedis-wsl@1.1.0(transitive)

• - Removedjackspeak@3.4.0(transitive)

• - Removedjs-beautify@1.15.1(transitive)

• - Removedjs-cookie@3.0.5(transitive)

• - Removedjsonfile@3.0.1(transitive)

• - Removedkind-of@3.2.2(transitive)

• - Removedlimiter@1.1.5(transitive)

• - Removedlinkify-it@3.0.3(transitive)

• - Removedliquidjs@9.43.0(transitive)

• - Removedlocaltunnel@2.0.2(transitive)

• - Removedlodash@4.17.21(transitive)

• - Removedlodash.isfinite@3.3.2(transitive)

• - Removedlru-cache@10.3.0(transitive)

• - Removedluxon@2.5.2(transitive)

• - Removedmarkdown-it@12.3.2(transitive)

• - Removedmime@1.4.1(transitive)

• - Removedmime-db@1.52.0(transitive)

• - Removedmime-types@2.1.35(transitive)

• - Removedminimatch@9.0.19.0.5(transitive)

• - Removedminipass@7.1.2(transitive)

• - Removedmitt@1.2.0(transitive)

• - Removednegotiator@0.6.3(transitive)

• - Removednopt@7.2.1(transitive)

• - Removedon-finished@2.3.0(transitive)

• - Removedopenurl@1.1.1(transitive)

• - Removedopn@5.3.0(transitive)

• - Removedpackage-json-from-dist@1.0.0(transitive)

• - Removedpath-scurry@1.11.1(transitive)

• - Removedportscanner@2.2.0(transitive)

• - Removedpretty@2.0.0(transitive)

• - Removedproto-list@1.2.4(transitive)

• - Removedrange-parser@1.2.1(transitive)

• - Removedraw-body@2.5.2(transitive)

• - Removedrequire-directory@2.1.1(transitive)

• - Removedrequires-port@1.0.0(transitive)

• - Removedresp-modifier@6.0.2(transitive)

• - Removedrx@4.1.0(transitive)

• - Removedsafer-buffer@2.1.2(transitive)

• - Removedsend@0.16.2(transitive)

• - Removedserve-index@1.9.1(transitive)

• - Removedserve-static@1.13.2(transitive)

• - Removedserver-destroy@1.0.1(transitive)

• - Removedsetprototypeof@1.1.01.2.0(transitive)

• - Removedsignal-exit@4.1.0(transitive)

• - Removedsocket.io@4.7.5(transitive)

• - Removedsocket.io-adapter@2.5.5(transitive)

• - Removedsocket.io-client@4.7.5(transitive)

• - Removedsocket.io-parser@4.2.4(transitive)

• - Removedstatuses@1.3.11.4.01.5.0(transitive)

• - Removedstream-throttle@0.1.3(transitive)

• - Removedstring-width@4.2.35.1.2(transitive)

• - Removedstrip-ansi@6.0.17.1.0(transitive)

• - Removedtoidentifier@1.0.1(transitive)

• - Removedua-parser-js@1.0.38(transitive)

• - Removedundici-types@5.26.5(transitive)

• - Removeduniversalify@0.1.2(transitive)

• - Removedutils-merge@1.0.1(transitive)

• - Removedvary@1.1.2(transitive)

• - Removedwrap-ansi@7.0.08.1.0(transitive)

• - Removedws@8.17.1(transitive)

• - Removedxmlhttprequest-ssl@2.0.0(transitive)

• - Removedy18n@5.0.8(transitive)

• - Removedyargs@17.1.117.7.2(transitive)

• - Removedyargs-parser@20.2.921.1.1(transitive)

• Updatedfast-glob@^3.2.12

• Updatedliquidjs@^10.4.0

• Updatedluxon@^3.2.1

• Updatedmarkdown-it@^13.0.1

• Updatedminimist@^1.2.7

• Updatedmoo@^0.5.2

• Updatedsemver@^7.3.8