Add webpack benchmark

jest.config.js

@@ -0,0 +1,13 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+const path = require("path");
+
+module.exports = {
+  rootDir: path.resolve(__dirname, "src"),
+  transformIgnorePatterns: [
+    "/node_modules/",
+    path.resolve(__dirname, "build")
+  ]
+};

src/fixtures/webpack/a.js

@@ -0,0 +1,5 @@
+import b from "./b.js";
+
+const message = import("./c.js").then(c => c.default + b);
+
+export default message;

src/fixtures/webpack/b.js

@@ -0,0 +1 @@
+module.exports = 42;

src/fixtures/webpack/c.js

@@ -0,0 +1 @@
+export default "Hello world";

src/mocks/chokidar/index.js

@@ -0,0 +1,3 @@
+module.exports = {
+  watch: () => {}
+};

src/mocks/clear-immediate.js

@@ -0,0 +1,9 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+const eventLoop = require("./event-loop");
+
+module.exports = task => {
+  eventLoop.cancel(task);
+};

src/mocks/event-loop.js

@@ -0,0 +1,27 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This is a very simple event loop implementation. It does not cover the exact behavior
+// in node, especially not the differences between process.nextTick and setImmediate.
+// It is, however, sufficient for the benchmark.
+const tasks = [];
+
+module.exports = {
+  schedule(task) {
+    tasks.push(task);
+  },
+  cancel(task) {
+    const i = tasks.indexOf(task);
+
+    if (i > -1) {
+      tasks.splice(i, 1);
+    }
+  },
+  run() {
+    let task;
+    while ((task = tasks.shift())) {
+      task();
+    }
+  }
+};

src/mocks/process.js

@@ -0,0 +1,24 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+const eventLoop = require("./event-loop");
+
+exports.nextTick = function(fn) {
+  const args = Array.prototype.slice.call(arguments, 1);
+  eventLoop.schedule(() => {
+    fn.apply(null, args);
+  });
+};
+
+exports.platform = exports.arch = exports.execPath = exports.title = "browser";
+exports.pid = 1;
+exports.browser = true;
+exports.env = {};
+exports.argv = [];
+exports.cwd = () => "/";
+exports.binding = name => {
+  throw new Error("No such module. (Possibly not yet loaded)");
+};
+exports.exit = exports.kill = exports.umask = exports.dlopen = exports.uptime = exports.memoryUsage = exports.uvCounters = () => {};
+exports.features = {};

src/mocks/set-immediate.js

@@ -0,0 +1,14 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+const eventLoop = require("./event-loop");
+
+module.exports = function(fn) {
+  const args = Array.prototype.slice.call(arguments, 1);
+  const task = () => {
+    fn.apply(null, args);
+  };
+  eventLoop.schedule(task);
+  return task;
+};

src/suite.js

@@ -22,5 +22,6 @@ suite.add(require("./source-map-benchmark"));
 suite.add(require("./typescript-benchmark"));
 suite.add(require("./uglify-js-benchmark"));
 suite.add(require("./uglify-es-benchmark"));
+suite.add(require("./webpack-benchmark"));
 
 module.exports = suite;

src/vfs.js

@@ -79,5 +79,18 @@ fs.writeFileSync(
   "third_party/vue.runtime.esm-nobuble-2.4.4.js",
   require("raw-loader!../third_party/vue.runtime.esm-nobuble-2.4.4.js")
 );
+fs.mkdirpSync("/src/fixtures/webpack");
+fs.writeFileSync(
+  "/src/fixtures/webpack/a.js",
+  require("raw-loader!./fixtures/webpack/a.js")
+);
+fs.writeFileSync(
+  "/src/fixtures/webpack/b.js",
+  require("raw-loader!./fixtures/webpack/b.js")
+);
+fs.writeFileSync(
+  "/src/fixtures/webpack/c.js",
+  require("raw-loader!./fixtures/webpack/c.js")
+);
 
 module.exports = fs;

src/webpack-benchmark.js

@@ -0,0 +1,49 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+const webpack = require("webpack");
+const eventLoop = require("./mocks/event-loop");
+
+const payloads = [
+  {
+    entry: "/src/fixtures/webpack/a.js"
+  }
+].map(({ entry }, i) => ({
+  entry,
+  output: {
+    path: "/dist/webpack/",
+    filename: `bundle.${i}.js`
+  },
+  // Using bail option in order to receive noisy errors in the benchmark if something went wrong
+  bail: true,
+  // We need to define that because Firefox has a Object.prototype.watch function
+  watch: false
+}));
+
+module.exports = {
+  name: "webpack",
+  fn() {
+    payloads.forEach(config => {
+      let finished = false;
+
+      eventLoop.schedule(() => {
+        const compiler = webpack(config);
+        compiler.run((err, stats) => {
+          if (err) {
+            throw err;
+          }
+          if (stats.hasErrors()) {
+            throw stats.compilation.errors[0];
+          }
+          finished = true;
+        });
+      });
+      eventLoop.run();
+
+      if (finished !== true) {
+        throw new Error("Webpack did not finish synchronously");
+      }
+    });
+  }
+};

src/webpack-benchmark.test.js

@@ -0,0 +1,41 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+const path = require("path");
+const webpack = require("webpack");
+const webpackConfig = require("../webpack.config.js");
+
+const outputFile = path.resolve(
+  __dirname,
+  "..",
+  "build",
+  "webpack-benchmark.test.js"
+);
+let webpackBenchmark;
+
+beforeAll(
+  () =>
+    new Promise((resolve, reject) => {
+      const baseConfig = webpackConfig[0];
+      const config = Object.assign({}, baseConfig, {
+        entry: require.resolve("./webpack-benchmark.js")
+      });
+      config.output = Object.assign({}, baseConfig.output, {
+        libraryTarget: "commonjs2",
+        path: path.dirname(outputFile),
+        filename: path.basename(outputFile)
+      });
+      const compiler = webpack(config);
+      compiler.run(err => {
+        if (err) {
+          reject(err);
+          return;
+        }
+        webpackBenchmark = require(outputFile);
+        resolve();
+      });
+    })
+);
+
+it("webpack runs to completion", () => void webpackBenchmark.fn());

webpack.config.js

@@ -19,10 +19,29 @@ module.exports = [
     resolve: {
       alias: {
         fs: require.resolve("./src/vfs"),
-        module: require.resolve("./src/mocks/dummy")
+        "graceful-fs": require.resolve("./src/vfs"),
+        module: require.resolve("./src/mocks/dummy"),
+        chokidar: require.resolve("./src/mocks/chokidar"),
+        "uglify-js": require.resolve("./src/mocks/dummy"),
+        // These modules are used by virtualfs to fake async fs calls
+        "core-js/library/fn/set-immediate": require.resolve(
+          "./src/mocks/set-immediate"
+        ),
+        "core-js/library/fn/clear-immediate": require.resolve(
+          "./src/mocks/clear-immediate"
+        )
       }
     },
+    node: {
+      setImmediate: false, // this disables also clearImmediate
+      process: false
+    },
     plugins: [
+      new webpack.ProvidePlugin({
+        setImmediate: require.resolve("./src/mocks/set-immediate"),
+        clearImmediate: require.resolve("./src/mocks/clear-immediate"),
+        process: require.resolve("./src/mocks/process")
+      }),
       new webpack.BannerPlugin({
         banner:
           "// Required for JavaScript engine shells.\n" +
@@ -46,10 +65,28 @@ module.exports = [
       alias: {
         define: require.resolve("./src/mocks/dummy"),
         fs: require.resolve("./src/vfs"),
-        module: require.resolve("./src/mocks/dummy")
+        "graceful-fs": require.resolve("./src/vfs"),
+        module: require.resolve("./src/mocks/dummy"),
+        chokidar: require.resolve("./src/mocks/chokidar"),
+        "uglify-js": require.resolve("./src/mocks/dummy"),
+        "core-js/library/fn/set-immediate": require.resolve(
+          "./src/mocks/set-immediate"
+        ),
+        "core-js/library/fn/clear-immediate": require.resolve(
+          "./src/mocks/clear-immediate"
+        )
       }
     },
+    node: {
+      setImmediate: false,
+      process: false
+    },
     plugins: [
+      new webpack.ProvidePlugin({
+        setImmediate: require.resolve("./src/mocks/set-immediate"),
+        clearImmediate: require.resolve("./src/mocks/clear-immediate"),
+        process: require.resolve("./src/mocks/process")
+      }),
       new CopyWebpackPlugin([{ from: "style.css" }, { from: "Logo.png" }]),
       new webpack.BannerPlugin({
         banner: