cjs-es - npm Package Compare versions

Comparing version 0.4.9 to 0.5.0

lib/analyzer.js

@@ -9,2 +9,3 @@ const {walk} = require("estree-walker");
   getRequireInfo,
+  getNestedExports
 } = require("./util");
@@ -106,2 +107,17 @@
   
+  function analyzeNestedExports(node) {
+    const nestedExports = getNestedExports(node);
+    if (!nestedExports || !nestedExports.name || context.scope.has(nestedExports.leftMost.name)) {
+      return;
+    }
+    nestedExports.leftMost.nestedExports = nestedExports;
+    nestedExports.leftMost.rootPos = context.topLevel.get().start;
+    if (nestedExports.leftMost.name === "module") {
+      context.moduleNodes.push(nestedExports.leftMost);
+    } else {
+      context.exportsNodes.push(nestedExports.leftMost);
+    }
+    context.skip();
+  }
+  
   function analyzeCallable(node) {
@@ -166,2 +182,3 @@ if (
         context.topLevel.enter(node, parent);
+        context.assignment.enter(node);
         if (context.scope) {
@@ -203,2 +220,4 @@ context.scope.enter(node);
       analyzeClass(node);
+    } else if (node.type === "MemberExpression") {
+      analyzeNestedExports(node);
     }
@@ -205,0 +224,0 @@ if (!context.nested && !context.topLevel.isTop()) {

lib/context.js

 const {
   createTopLevelAnalyzer,
   createScopeAnalyzer,
+  createAssignmentAnalyzer,
   hasDefaultComment
@@ -52,2 +53,3 @@ } = require("./util");
   context.scope = options.nested ? createScopeAnalyzer(context.ast) : null;
+  context.assignment = createAssignmentAnalyzer();
   context.walkContext = null;
@@ -54,0 +56,0 @@ context.skip = () => {

lib/export-writer.js

 function createExportWriter(context) {
   context.hasNonTopLevelExport = false;
   context.defaultExports = [];
-  context.namedExports = [];
+  context.namedExports = new Map;
   return {write};
@@ -12,16 +12,23 @@
     for (const node of context.moduleNodes.concat(context.exportsNodes)) {
-      if (!node.exported && !node.declared) {
+      if (!node.exported && !node.declared && !node.nestedExports) {
         context.hasNonTopLevelExport = true;
-      } else if (
-        node.exported && node.exported.name ||
-        node.declared && node.declared.exported.name
-      ) {
-        context.namedExports.push(node);
-      } else {
+        continue;
+      }
+      const name = node.exported && node.exported.name ||
+        node.declared && node.declared.exported.name ||
+        node.nestedExports && node.nestedExports.name;
+      if (!name) {
         context.defaultExports.push(node);
+        continue;
       }
+      let namedExport = context.namedExports.get(name);
+      if (!namedExport) {
+        namedExport = [];
+        context.namedExports.set(name, namedExport);
+      }
+      namedExport.push(node);
     }
     if (
       context.hasNonTopLevelExport ||
-      context.namedExports.length && context.defaultExports.length ||
+      context.namedExports.size && context.defaultExports.length ||
       context.defaultExports.length > 1 // but why?
@@ -187,7 +194,40 @@ ) {
   function writeNamedExport() {
-    for (const node of context.namedExports) {
-      if (node.declared) {
-        writeNamedDeclare(node);
+    for (const [name, nodes] of context.namedExports) {
+      let init = 0;
+      let assignment = 0;
+      let declared = 0;
+      for (const node of nodes) {
+        if (node.declared) {
+          declared++;
+          init++;
+          assignment++;
+        } else if (node.exported) {
+          init++;
+          assignment++;
+        } else if (node.nestedExports.node.isAssignment) {
+          assignment++;
+        }
+      }
+      if (init === 1 && (!declared || nodes.length === 1)) {
+        for (const node of nodes) {
+          if (node.declared) {
+            writeNamedDeclare(node);
+          } else if (node.exported) {
+            writeNamedExports(node, assignment > 1 ? "let" : "const", nodes.length > 1);
+          } else {
+            writeNestedExports(node);
+          }
+        }
       } else {
-        writeNamedExports(node);
+        for (const node of nodes) {
+          if (node.declared) {
+            node.nestedExports = node.declared.exported;
+          } else if (node.exported) {
+            node.nestedExports = node.exported;
+          }
+          writeNestedExports(node);
+        }
+        writeNamedInit(nodes.reduce((node, curr) => {
+          return curr.rootPos < node.rootPos ? curr : node;
+        }), name);
       }
@@ -221,8 +261,8 @@ }
   
-  function writeNamedExports(node) {
-    if (node.exported.value.type !== "Identifier" && !node.exported.required) {
+  function writeNamedExports(node, kind = "const", shareExport = false) {
+    if (node.exported.value.type !== "Identifier" && !node.exported.required || shareExport) {
       context.s.overwrite(
         node.exported.leftMost.start,
         node.exported.value.start,
-        `const _export_${node.exported.name}_ = `,
+        `${kind} _export_${node.exported.name}_ = `,
         {contentOnly: true}
@@ -249,4 +289,20 @@ );
   }
+  
+  function writeNestedExports(node) {
+    context.s.overwrite(
+      node.nestedExports.node.start,
+      node.nestedExports.node.end,
+      `_export_${node.nestedExports.name}_`,
+      {contentOnly: true}
+    );
+  }
+  
+  function writeNamedInit(node, name) {
+    context.s.appendLeft(
+      node.rootPos,
+      `let _export_${name}_;\nexport {_export_${name}_ as ${name}};\n`
+    );
+  }
 }
 
 module.exports = {createExportWriter};

lib/util.js

@@ -59,4 +59,25 @@ const {attachScopes} = require("rollup-pluginutils");
 
-function getExportInfo(node) {
-  if (node.left.type !== "MemberExpression") {
+function createAssignmentAnalyzer() {
+  return {enter};
+  
+  function enter(node) {
+    if (node.type === "AssignmentExpression" || node.type === "AssignmentPattern") {
+      node.left.isAssignment = true;
+    } else if (node.type === "UpdateExpression") {
+      node.argument.isAssignment = true;
+    } else if (node.type === "ObjectPattern" && node.isAssignment) {
+      for (const prop of node.properties) {
+        prop.value.isAssignment = true;
+      }
+    } else if (node.type === "ArrayPattern" && node.isAssignment) {
+      for (const el of node.elements) {
+        el.isAssignment = true;
+      }
+    }
+  }
+}
+
+function getNestedExports(node) {
+  // extract export info from member expression.
+  if (node.type !== "MemberExpression") {
     return;
@@ -66,14 +87,14 @@ }
   let isNamed = false;
-  if (node.left.object.name === "module" && node.left.property.name === "exports") {
-    // module.exports = ...
+  if (node.object.name === "module" && node.property.name === "exports") {
+    // module.exports
     isModule = true;
   } else if (
-    node.left.object.type === "MemberExpression" &&
-    node.left.object.object.name === "module" &&
-    node.left.object.property.name === "exports"
+    node.object.type === "MemberExpression" &&
+    node.object.object.name === "module" &&
+    node.object.property.name === "exports"
   ) {
-    // module.exports.foo = ...
+    // module.exports.foo
     isModule = true;
     isNamed = true;
-  } else if (node.left.object.name === "exports") {
+  } else if (node.object.name === "exports") {
     // exports.foo = ...
@@ -85,8 +106,21 @@ isNamed = true;
   return {
-    name: isNamed && node.left.property.name,
+    node,
+    name: isNamed ? node.property.name : undefined,
+    leftMost: isModule && isNamed ? node.object.object : node.object
+  };
+}
+
+function getExportInfo(node) {
+  const exportInfo = getNestedExports(node.left);
+  if (!exportInfo) {
+    return;
+  }
+  return {
+    node: exportInfo.node,
+    name: exportInfo.name,
+    leftMost: exportInfo.leftMost,
     left: node.left,
-    leftMost: isModule && isNamed ? node.left.object.object : node.left.object,
     key: node.left.property,
     value: node.right,
-    object: !isNamed && node.right.type === "ObjectExpression" && node.right.properties.length ?
+    object: !exportInfo.name && node.right.type === "ObjectExpression" && node.right.properties.length ?
       getObjectInfo(node.right) : null,
@@ -273,5 +307,7 @@ required: node.right.type === "CallExpression" && getRequireInfo(node.right),
   createTopLevelAnalyzer,
+  createAssignmentAnalyzer,
   getDeclareExport,
   getDeclareImport,
   getDynamicImport,
+  getNestedExports,
   getExportInfo,
@@ -278,0 +314,0 @@ getRequireInfo,

package.json

 {
   "name": "cjs-es",
-  "version": "0.4.9",
+  "version": "0.5.0",
   "description": "Transform CommonJS module into ES module.",
@@ -5,0 +5,0 @@ "keywords": [

README.md

@@ -140,4 +140,6 @@ cjs-es
 
-If the `require`/`module`/`exports` statement are nested, they would be hoisted. Require statement:
+If the `require`/`module`/`exports` statement are nested, they would be hoisted.
 
+#### Require statement
+
 ```js
@@ -158,5 +160,25 @@ if (foo) {
 
-Export statement:
+#### Export statement
 
 ```js
+function test(key) {
+  exports[key] = "foo";
+}
+exports.foo = "FOO";
+```
+
+Result:
+
+```js
+let _exports_ = {};
+function test(key) {
+  _exports_[key] = "foo";
+}
+_exports_.foo = "FOO";
+export default _exports_;
+```
+
+In some cases, there is no need to hoist the export statement:
+
+```js
 function test() {
@@ -171,8 +193,7 @@ return exports.foo();
 ```js
-let _exports_ = {};
 function test() {
-  return _exports_.foo();
+  return _export_foo_();
 }
-_exports_.foo = () => "foo";
-export default _exports_;
+const _export_foo_ = () => "foo";
+export {_export_foo_ as foo};
 ```
@@ -242,2 +263,6 @@
 
+* 0.5.0 (Jul 19, 2018)
+
+  - Add: don't hoist export statements in some cases.
+
 * 0.4.9 (Jun 29, 2018)
@@ -244,0 +269,0 @@

New alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Fixed alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

44272

increased by9.82%

Lines of code

1092

increased by10.86%

Number of lines in readme file

353

increased by7.62%

No dependency changes