streamiterator - npm Package Compare versions

Comparing version 1.0.6 to 1.0.7

distr/polyfill.js

@@ -15,5 +15,5 @@ "use strict";
 		value: function asyncIterator() {
-			return (0, _streamiterator2.default)(this)[Symbol.asyncIterator]();
+			return _streamiterator2.default.createStreamIterator(this)[Symbol.asyncIterator]();
 		}
 	});
 }

distr/streamiterator.js

@@ -14,82 +14,101 @@ "use strict";
 
-function streamIterator(stream) {
-	if (typeof stream[Symbol.asyncIterator] === "function") {
-		return stream;
-	}
-	return _defineProperty({}, Symbol.asyncIterator, function () {
-		var resolvers = [];
-		var results = [];
-		var closed = false;
+function createStreamIterator(stream) {
+	var _result;
 
-		function copyResults() {
-			while (resolvers.length > 0 && results.length > 0) {
-				resolvers.shift()(results.shift());
-			}
-			while (resolvers.length > 0 && closed) {
+	var resolvers = [];
+	var results = [];
+	var inputClosed = false;
+	var outputClosed = false;
+
+	function copyResults() {
+		while (!outputClosed && resolvers.length > 0 && results.length > 0) {
+			resolvers.shift()(results.shift());
+		}
+		if (inputClosed || outputClosed) {
+			while (resolvers.length > 0) {
 				resolvers.shift()({ value: undefined, done: true });
 			}
-			if (resolvers.length > 0) {
-				stream.resume();
-			} else {
-				if (!closed) {
-					stream.pause();
-				}
+		}
+		if (resolvers.length > 0) {
+			stream.resume();
+		} else {
+			if (!inputClosed) {
+				stream.pause();
 			}
 		}
+	}
 
-		function onData(value) {
-			results.push({ value: value, done: false });
-			copyResults();
+	function pushResult(promise) {
+		if (!inputClosed) {
+			results.push(promise);
 		}
+	}
 
-		function onError(error) {
-			results.push(Promise.reject(error));
-			close();
-		}
+	function onData(value) {
+		pushResult({ value: value, done: false });
+		copyResults();
+	}
 
-		function onEnd() {
-			close();
-		}
+	function onError(error) {
+		pushResult(Promise.reject(error));
+		close();
+	}
 
-		function close() {
-			if (!closed) {
-				closed = true;
-				stream.removeListener("data", onData).removeListener("error", onError).removeListener("end", onEnd);
-				// .destroy?.()
-				if (stream.destroy) {
-					stream.destroy();
-				}
+	function onEnd() {
+		close();
+	}
+
+	function close() {
+		if (!inputClosed) {
+			inputClosed = true;
+			stream //
+			.removeListener("data", onData).removeListener("error", onError).removeListener("end", onEnd);
+			// .destroy?.()
+			if (stream.destroy) {
+				stream.destroy();
 			}
-			copyResults();
 		}
+		copyResults();
+	}
 
-		stream.on("data", onData).on("error", onError).on("end", onEnd).pause();
+	stream //
+	.on("data", onData).on("error", onError).on("end", onEnd).pause();
 
-		return {
-			next: function next() {
-				return new Promise(function (resolve) {
-					resolvers.push(resolve);
-					copyResults();
+	var result = (_result = {}, _defineProperty(_result, Symbol.asyncIterator, function () {
+		return result;
+	}), _defineProperty(_result, "next", function next() {
+		return new Promise(function (resolve) {
+			resolvers.push(resolve);
+			copyResults();
+		});
+	}), _defineProperty(_result, "return", function _return(value) {
+		return new Promise(function (resolve) {
+			if (resolvers.length === 0) {
+				finish();
+			} else {
+				var last = resolvers.pop();
+				resolvers.push(function (value) {
+					last(value);
+					finish();
 				});
-			},
-			return: function _return(value) {
-				return new Promise(function (resolve) {
-					if (resolvers.length === 0) {
-						finish();
-					} else {
-						var last = resolvers.pop();
-						resolvers.push(function (result) {
-							last(result);
-							finish();
-						});
-					}
-					function finish() {
-						resolve({ value: value, done: true });
-						close();
-					}
-				});
 			}
-		};
-	});
+			function finish() {
+				outputClosed = true;
+				resolve({ value: value, done: true });
+				close();
+			}
+		});
+	}), _result);
+	return result;
 }
+
+function streamIterator(stream) {
+	if (typeof stream[Symbol.asyncIterator] === "function") {
+		return stream;
+	} else {
+		return createStreamIterator(stream);
+	}
+}
+
+Object.assign(streamIterator, { createStreamIterator: createStreamIterator });
 module.exports = exports["default"];

package.json

 {
   "name": "streamiterator",
-  "version": "1.0.6",
+  "version": "1.0.7",
   "description": "converts ReadableStream into AsyncIterator",
@@ -8,3 +8,5 @@ "main": "distr/streamiterator.js",
     "build": "babel source --out-dir distr",
-    "prepare": "npm run build"
+    "prettier": "prettier --write $(cat .prettier) 'source/**/*.js' '*.js'",
+    "prepare": "npm run prettier && npm run build",
+    "test": "jest"
   },
@@ -16,7 +18,10 @@ "repository": "https://github.com/vadzim/streamiterator",
     "babel-cli": "^6.26.0",
+    "babel-jest": "^20.0.3",
     "babel-plugin-add-module-exports": "^0.2.1",
     "babel-preset-env": "^1.6.0",
     "babel-preset-flow": "^6.23.0",
-    "babel-preset-stage-0": "^6.24.1"
+    "babel-preset-stage-0": "^6.24.1",
+    "jest": "^20.0.4",
+    "prettier": "^1.5.3"
   }
 }

README.md

 # streamiterator
-converts ReadableStream into AsyncIterator
+Converts ReadableStream into AsyncIterator.
+
+### Using ###
+
+With this module you can ![iterate](https://github.com/tc39/proposal-async-iteration) over a stream with a plain loop:
+
+```js
+import streamIterator from "streamiterator"
+// or
+// const streamIterator = require("streamiterator")
+
+async function DoIt(stream) {
+	for await (const value of streamIterator(stream)) {
+		console.log(`Read: ${value}`)
+	}
+}
+```
+
+As of August, 2017 you need smth like either ![babel](http://babeljs.io/) or ![node.js 8.4.0 or higher](https://nodejs.org/) with `--harmony_async_iteration` switch to be able to use `for await` operator.
+
+Of course, you can iterate without `for await`, though it is not so nice as using syntactic suger:
+
+```js
+import streamIterator from "streamiterator"
+
+async function DoIt(stream) {
+	for (let done, value, iterator = streamIterator(stream); {done, value} = await iterator.next(), !done;) {
+		console.log(`Read: ${value}`)
+	}
+}
+```
+
+If the stream emits an error, it will be thrown while looping. Wrap your loop in `try..catch` to deal with it.
+
+If eventually streams will support async iteration natively then this module will just redirect iteration to those native mechanism. No overhead will be added.
+
+### Polyfill ###
+
+But if you believe that writing `streamIterator(...)` everywhere is a bullshit and in your world streams have to be iterable from the scratch right now, then you can import `streamiterator/polyfill` in the root of your project and iterate just on streams:
+
+```js
+import "streamiterator/polyfill"
+import fs from "fs"
+
+async function DoIt() {
+	for await (const data of fs.createReadableStream("./data.txt")) {
+		console.log(data)
+	}
+}
+```
+
+Note that you don't need to import `streamiterator/polyfill` in every file of your project. Just in the `main.js` or similar.
+
+### Contributing ###
+
+__Please contribute!__
+All contributions are greatly appreciated no matter how small or large the contribution is.
+Whether it's a small grammar fix in the README, a huge bug fix, or just an issue report, you will be recognized as a 'Contributor' to this project.
+
+Please, feel free to ![open an issue](https://github.com/vadzim/streamiterator/issues) if you have any question.

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

112993

increased by56.45%

Number of package files

9

increased by12.5%

Lines of code

110

increased by15.79%

Number of lines in readme file

62

increased by1966.67%

Worsened metrics

Dev dependency count

8

increased by60%

No dependency changes