Add fallbacks option to prevent creating chunks with inlined workers

Author: TrySound

createInlineWorker.js

@@ -18,6 +18,9 @@ module.exports = function(content, url) {
       return new Worker('data:application/javascript,' + encodeURIComponent(content));
     }
   } catch(e) {
+    if (!url) {
+      throw Error('Inline worker is not supported');
+    }
     return new Worker(url);
   }
 }

index.js

@@ -9,7 +9,8 @@ const getWorker = (file, content, query) => {
   const workerPublicPath = `__webpack_public_path__ + ${JSON.stringify(file)}`;
   if (query.inline) {
     const createInlineWorkerPath = JSON.stringify(`!!${path.resolve('createInlineWorker.js')}`);
-    return `require(${createInlineWorkerPath})(${JSON.stringify(content)}, ${workerPublicPath})`;
+    const fallbackWorkerPath = query.fallback === false ? 'null' : workerPublicPath;
+    return `require(${createInlineWorkerPath})(${JSON.stringify(content)}, ${fallbackWorkerPath})`;
   }
   return `new Worker(${workerPublicPath})`;
 };
@@ -55,6 +56,9 @@ module.exports.pitch = function pitch(request) {
     if (entries[0]) {
       const workerFile = entries[0].files[0];
       const workerFactory = getWorker(workerFile, compilation.assets[workerFile].source(), query);
+      if (query.fallback === false) {
+        delete this._compilation.assets[workerFile];
+      }
       return callback(null, `module.exports = function() {\n\treturn ${workerFactory};\n};`);
     }
     return callback(null, null);

test/fixtures/no-fallbacks/entry.js

@@ -0,0 +1,2 @@
+const w1 = require('./w1.js');
+const w2 = require('./w2.js');

test/fixtures/no-fallbacks/w1.js

@@ -0,0 +1 @@
+// w1 inlined without fallback

test/fixtures/no-fallbacks/w2.js

@@ -0,0 +1 @@
+// w2 inlined without fallback

test/index.js

@@ -147,4 +147,36 @@ describe('worker-loader', () => {
       }
     })
   );
+
+  it.only('should not add fallback chunks with inline and fallback === false', () =>
+    makeBundle('no-fallbacks', {
+      module: {
+        rules: [
+          {
+            test: /(w1|w2)\.js$/,
+            loader: '../index.js',
+            options: {
+              inline: true,
+              fallback: false
+            },
+          },
+        ],
+      },
+    }).then((stats) => {
+      const workerFiles = stats.toJson('minimal').children
+        .map(item => item.chunks)
+        .reduce((acc, item) => acc.concat(item), [])
+        .map(item => item.files)
+        .map(item => `expected/no-fallbacks/${item}`);
+      const bundleFile = stats.toJson('minimal').chunks
+        .map(item => item.files)
+        .reduce((acc, item) => acc.concat(item), [])
+        .map(item => `expected/no-fallbacks/${item}`)[0];
+      assert(bundleFile);
+      assert.equal(fs.readdirSync('expected/no-fallbacks').length, 1);
+      assert.equal(workerFiles.length, 0);
+      assert.notEqual(readFile(bundleFile).indexOf('// w1 inlined without fallbacks'), -1);
+      assert.notEqual(readFile(bundleFile).indexOf('// w2 inlined without fallbacks'), -1);
+    })
+  );
 });