Merge pull request #6894 from webpack/bugfix/css-stuff

fixes for mini-css-extract-plugin

lib/Compilation.js

@@ -158,8 +158,6 @@ class Compilation extends Tapable {
 			beforeChunkAssets: new SyncHook([]),
 			additionalChunkAssets: new SyncHook(["chunks"]),
 
-			records: new SyncHook(["compilation", "records"]),
-
 			additionalAssets: new AsyncSeriesHook([]),
 			optimizeChunkAssets: new AsyncSeriesHook(["chunks"]),
 			afterOptimizeChunkAssets: new SyncHook(["chunks"]),
@@ -278,6 +276,9 @@ class Compilation extends Tapable {
 		if (this.cache && this.cache[cacheName]) {
 			const cacheModule = this.cache[cacheName];
 
+			if (typeof cacheModule.updateCacheModule === "function")
+				cacheModule.updateCacheModule(module);
+
 			let rebuild = true;
 			if (this.fileTimestamps && this.contextTimestamps) {
 				rebuild = cacheModule.needRebuild(

lib/ContextModule.js

@@ -45,6 +45,12 @@ class ContextModule extends Module {
 			throw new Error("options.mode is a required option");
 	}
 
+	updateCacheModule(module) {
+		this.resolveDependencies = module.resolveDependencies;
+		this.options = module.options;
+		this.resolveOptions = module.resolveOptions;
+	}
+
 	prettyRegExp(regexString) {
 		// remove the "/" at the front and the beginning
 		// "/foo/" -> "foo"

lib/HotUpdateChunkTemplate.js

@@ -47,7 +47,7 @@ module.exports = class HotUpdateChunkTemplate extends Tapable {
 		hotUpdateChunk.removedModules = removedModules;
 		const modulesSource = Template.renderChunkModules(
 			hotUpdateChunk,
-			() => true,
+			m => typeof m.source === "function",
 			moduleTemplate,
 			dependencyTemplates
 		);

lib/Module.js

@@ -338,5 +338,6 @@ Module.prototype.build = null;
 Module.prototype.source = null;
 Module.prototype.size = null;
 Module.prototype.nameForCondition = null;
+Module.prototype.updateCacheModule = null;
 
 module.exports = Module;

lib/NormalModule.js

@@ -122,6 +122,15 @@ class NormalModule extends Module {
 		return this.resource;
 	}
 
+	updateCacheModule(module) {
+		this.userRequest = module.userRequest;
+		this.parser = module.parser;
+		this.generator = module.generator;
+		this.resource = module.resource;
+		this.loaders = module.loaders;
+		this.resolveOptions = module.resolveOptions;
+	}
+
 	createSourceForAsset(name, content, sourceMap) {
 		if (!sourceMap) {
 			return new RawSource(content);