Support for SplitChunksPlugin

src/loader.js

@@ -18,6 +18,9 @@ import loaderUtils from 'loader-utils';
 import SingleEntryPlugin from 'webpack/lib/SingleEntryPlugin';
 import WebWorkerTemplatePlugin from 'webpack/lib/webworker/WebWorkerTemplatePlugin';
 import FetchCompileWasmTemplatePlugin from 'webpack/lib/web/FetchCompileWasmTemplatePlugin';
+import JsonpTemplatePlugin from 'webpack/lib/web/JsonpTemplatePlugin'
+import SplitChunksPlugin from 'webpack/lib/optimize/SplitChunksPlugin'
+import { ConcatSource } from 'webpack-sources'
 import WORKER_PLUGIN_SYMBOL from './symbol';
 
 const NAME = 'WorkerPluginLoader';
@@ -41,7 +44,7 @@ export function pitch (request) {
   const chunkFilename = compilerOptions.output.chunkFilename.replace(/\.([a-z]+)$/i, '.worker.$1');
   const workerOptions = {
     filename: chunkFilename.replace(/\[(?:chunkhash|contenthash)(:\d+(?::\d+)?)?\]/g, '[hash$1]'),
-    chunkFilename,
+    chunkFilename: compilerOptions.output.chunkFilename,
     globalObject: pluginOptions.globalObject || 'self'
   };
 
@@ -58,6 +61,13 @@ export function pitch (request) {
 
   const workerCompiler = this._compilation.createChildCompiler(NAME, workerOptions, plugins);
   workerCompiler.context = this._compiler.context;
+
+  const splitChunks = compilerOptions.optimization && compilerOptions.optimization.splitChunks
+  if (splitChunks) {
+    (new SplitChunksPlugin(splitChunks)).apply(workerCompiler);
+  }
+
+  (new JsonpTemplatePlugin()).apply(workerCompiler);
   (new WebWorkerTemplatePlugin(workerOptions)).apply(workerCompiler);
   (new FetchCompileWasmTemplatePlugin({
     mangleImports: compilerOptions.optimization.mangleWasmImports
@@ -70,13 +80,29 @@ export function pitch (request) {
       if (!compilation.cache[subCache]) compilation.cache[subCache] = {};
       compilation.cache = compilation.cache[subCache];
     }
+
+    compilation.hooks.optimizeChunkAssets.tapAsync(NAME, (chunks, callback) => {
+      const allFiles = chunks.filter(chunk => chunk.name !== options.name).reduce((accumulated, chunk) => {
+        return accumulated.concat(chunk.files);
+      }, []);
+      const uniqueFiles = [...new Set(allFiles)];
+
+      if (uniqueFiles.length) {
+        // Sort to ensure the output is predictable.
+        uniqueFiles.sort();
+        const file = chunks.find(c => c.name === options.name).files[0];
+        compilation.assets[file] = new ConcatSource(`importScripts(${uniqueFiles.map(chunk => `${JSON.stringify(chunk)}`).join(', ')});\n\n`, compilation.assets[file]);
+      }
+
+      callback();
+    })
   });
 
   workerCompiler.runAsChild((err, entries, compilation) => {
     if (!err && compilation.errors && compilation.errors.length) {
       err = compilation.errors[0];
     }
-    const entry = entries && entries[0] && entries[0].files[0];
+    const entry = entries && entries[entries.length - 1] && entries[entries.length - 1].files[0];
     if (!err && !entry) err = Error(`WorkerPlugin: no entry for ${request}`);
     if (err) return cb(err);
     return cb(null, `${options.esModule ? 'export default' : 'module.exports ='} __webpack_public_path__ + ${JSON.stringify(entry)}`);