From e59541723dee6f3a372671eb45973b2b5ed3e115 Mon Sep 17 00:00:00 2001
From: Mike Evans <mike.evans@numical.com>
Date: Thu, 8 Jun 2017 05:48:38 +0100
Subject: [PATCH] fix: don't extract from common async chunks (#508)

---
 index.js                                  | 14 +++++++++-----
 test/cases/common-async/a.js              |  2 ++
 test/cases/common-async/a.txt             |  1 +
 test/cases/common-async/b.js              |  3 +++
 test/cases/common-async/b.txt             |  1 +
 test/cases/common-async/c.txt             |  1 +
 test/cases/common-async/expected/file.css |  3 +++
 test/cases/common-async/index.js          | 14 ++++++++++++++
 test/cases/common-async/webpack.config.js | 17 +++++++++++++++++
 9 files changed, 51 insertions(+), 5 deletions(-)
 create mode 100644 test/cases/common-async/a.js
 create mode 100644 test/cases/common-async/a.txt
 create mode 100644 test/cases/common-async/b.js
 create mode 100644 test/cases/common-async/b.txt
 create mode 100644 test/cases/common-async/c.txt
 create mode 100644 test/cases/common-async/expected/file.css
 create mode 100644 test/cases/common-async/index.js
 create mode 100644 test/cases/common-async/webpack.config.js

diff --git a/index.js b/index.js
index 0b7b992c..e6ee9e7a 100644
--- a/index.js
+++ b/index.js
@@ -19,11 +19,15 @@ function ExtractTextPluginCompilation() {
 	this.modulesByIdentifier = {};
 }
 
+function isInitialOrHasNoParents(chunk) {
+        return chunk.isInitial() || chunk.parents.length === 0;
+}
+
 ExtractTextPlugin.prototype.mergeNonInitialChunks = function(chunk, intoChunk, checkedChunks) {
 	if(!intoChunk) {
 		checkedChunks = [];
 		chunk.chunks.forEach(function(c) {
-			if(c.isInitial()) return;
+			if(isInitialOrHasNoParents(c)) return;
 			this.mergeNonInitialChunks(c, chunk, checkedChunks);
 		}, this);
 	} else if(checkedChunks.indexOf(chunk) < 0) {
@@ -33,7 +37,7 @@ ExtractTextPlugin.prototype.mergeNonInitialChunks = function(chunk, intoChunk, c
 			module.addChunk(intoChunk);
 		});
 		chunk.chunks.forEach(function(c) {
-			if(c.isInitial()) return;
+			if(isInitialOrHasNoParents(c)) return;
 			this.mergeNonInitialChunks(c, intoChunk, checkedChunks);
 		}, this);
 	}
@@ -262,7 +266,7 @@ ExtractTextPlugin.prototype.apply = function(compiler) {
 			});
 			async.forEach(chunks, function(chunk, callback) {
 				var extractedChunk = extractedChunks[chunks.indexOf(chunk)];
-				var shouldExtract = !!(options.allChunks || chunk.isInitial());
+				var shouldExtract = !!(options.allChunks || isInitialOrHasNoParents(chunk));
 				async.forEach(chunk.modules.slice(), function(module, callback) {
 					var meta = module[NS];
 					if(meta && (!meta.options.id || meta.options.id === id)) {
@@ -298,11 +302,11 @@ ExtractTextPlugin.prototype.apply = function(compiler) {
 			}, function(err) {
 				if(err) return callback(err);
 				extractedChunks.forEach(function(extractedChunk) {
-					if(extractedChunk.isInitial())
+					if(isInitialOrHasNoParents(extractedChunk))
 						this.mergeNonInitialChunks(extractedChunk);
 				}, this);
 				extractedChunks.forEach(function(extractedChunk) {
-					if(!extractedChunk.isInitial()) {
+					if(!isInitialOrHasNoParents(extractedChunk)) {
 						extractedChunk.modules.slice().forEach(function(module) {
 							extractedChunk.removeModule(module);
 						});
diff --git a/test/cases/common-async/a.js b/test/cases/common-async/a.js
new file mode 100644
index 00000000..2d7d820b
--- /dev/null
+++ b/test/cases/common-async/a.js
@@ -0,0 +1,2 @@
+require("./a.txt");
+require("./b.txt");
diff --git a/test/cases/common-async/a.txt b/test/cases/common-async/a.txt
new file mode 100644
index 00000000..78981922
--- /dev/null
+++ b/test/cases/common-async/a.txt
@@ -0,0 +1 @@
+a
diff --git a/test/cases/common-async/b.js b/test/cases/common-async/b.js
new file mode 100644
index 00000000..caac53f4
--- /dev/null
+++ b/test/cases/common-async/b.js
@@ -0,0 +1,3 @@
+require("./a.txt");
+require("./c.txt");
+
diff --git a/test/cases/common-async/b.txt b/test/cases/common-async/b.txt
new file mode 100644
index 00000000..61780798
--- /dev/null
+++ b/test/cases/common-async/b.txt
@@ -0,0 +1 @@
+b
diff --git a/test/cases/common-async/c.txt b/test/cases/common-async/c.txt
new file mode 100644
index 00000000..f2ad6c76
--- /dev/null
+++ b/test/cases/common-async/c.txt
@@ -0,0 +1 @@
+c
diff --git a/test/cases/common-async/expected/file.css b/test/cases/common-async/expected/file.css
new file mode 100644
index 00000000..de980441
--- /dev/null
+++ b/test/cases/common-async/expected/file.css
@@ -0,0 +1,3 @@
+a
+b
+c
diff --git a/test/cases/common-async/index.js b/test/cases/common-async/index.js
new file mode 100644
index 00000000..624fa419
--- /dev/null
+++ b/test/cases/common-async/index.js
@@ -0,0 +1,14 @@
+require.ensure(
+	[],
+	function() {
+		require("./a.js");
+	},
+	'async-chunk-a'
+);
+require.ensure(
+	[],
+	function() {
+		require("./b.js");
+	},
+	'async-chunk-b'
+);
diff --git a/test/cases/common-async/webpack.config.js b/test/cases/common-async/webpack.config.js
new file mode 100644
index 00000000..758d08a1
--- /dev/null
+++ b/test/cases/common-async/webpack.config.js
@@ -0,0 +1,17 @@
+var webpack = require('webpack');
+var ExtractTextPlugin = require("../../../index");
+
+module.exports = {
+	entry: "./index",
+	plugins: [
+		new webpack.optimize.CommonsChunkPlugin({
+			name: 'common',
+			filename: 'common.js',
+			chunks: ['async-chunk-a', 'async-chunk-b']
+		}),
+		new ExtractTextPlugin({
+			filename: "file.css",
+			allChunks: true
+		})
+	]
+};