Add the ability to run web_benchmarks with Wasm (#5611)

This uses the same run flags that the flutter benchmark tests use:
https://github.com/flutter/flutter/blob/master/dev/devicelab/lib/tasks/web_benchmarks.dart#L36-L40

CC @kevmoo

packages/web_benchmarks/CHANGELOG.md

@@ -1,3 +1,12 @@
+## 1.0.0
+
+* **Breaking change:** replace the `useCanvasKit` parameter in the `serveWebBenchmark`
+method with a new parameter `compilationOptions`, which allows you to:
+  * specify the web renderer to use for the benchmark app (html, canvaskit, or skwasm)
+  * specify whether to use WebAssembly to build the benchmark app
+* **Breaking change:** `serveWebBenchmark` now uses `canvaskit` instead of `html` as the
+default web renderer.
+
 ## 0.1.0+11
 
 * Migrates benchmark recorder from `dart:html` to `package:web` to support WebAssembly.

packages/web_benchmarks/lib/client.dart

@@ -53,15 +53,18 @@ Future<void> runBenchmarks(
   final Uri currentUri = Uri.parse(window.location.href);
   // Create a new URI with the current 'page' value set to [initialPage] to
   // ensure the benchmark app is reloaded at the proper location.
-  final Uri newUri = Uri(
+  final String newUri = Uri(
     scheme: currentUri.scheme,
     host: currentUri.host,
     port: currentUri.port,
     path: initialPage,
-  );
+  ).toString();
 
   // Reloading the window will trigger the next benchmark to run.
-  window.location.replace(newUri.toString());
+  await _client.printToConsole(
+    'Client preparing to reload the window to: "$newUri"',
+  );
+  window.location.replace(newUri);
 }
 
 Future<void> _runBenchmark(String? benchmarkName) async {

packages/web_benchmarks/lib/server.dart

@@ -9,9 +9,11 @@ import 'package:logging/logging.dart';
 
 import 'src/benchmark_result.dart';
 import 'src/common.dart';
+import 'src/compilation_options.dart';
 import 'src/runner.dart';
 
 export 'src/benchmark_result.dart';
+export 'src/compilation_options.dart';
 
 /// The default port number used by the local benchmark server.
 const int defaultBenchmarkServerPort = 9999;
@@ -43,12 +45,12 @@ const int defaultChromeDebugPort = 10000;
 Future<BenchmarkResults> serveWebBenchmark({
   required io.Directory benchmarkAppDirectory,
   required String entryPoint,
-  required bool useCanvasKit,
   int benchmarkServerPort = defaultBenchmarkServerPort,
   int chromeDebugPort = defaultChromeDebugPort,
   bool headless = true,
   bool treeShakeIcons = true,
   String initialPage = defaultInitialPage,
+  CompilationOptions compilationOptions = const CompilationOptions(),
 }) async {
   // Reduce logging level. Otherwise, package:webkit_inspection_protocol is way too spammy.
   Logger.root.level = Level.INFO;
@@ -56,10 +58,10 @@ Future<BenchmarkResults> serveWebBenchmark({
   return BenchmarkServer(
     benchmarkAppDirectory: benchmarkAppDirectory,
     entryPoint: entryPoint,
-    useCanvasKit: useCanvasKit,
     benchmarkServerPort: benchmarkServerPort,
     chromeDebugPort: chromeDebugPort,
     headless: headless,
+    compilationOptions: compilationOptions,
     treeShakeIcons: treeShakeIcons,
     initialPage: initialPage,
   ).run();

packages/web_benchmarks/lib/src/compilation_options.dart

@@ -0,0 +1,38 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/// Compilation options for bulding a Flutter web app.
+///
+/// This object holds metadata that is used to determine how the benchmark app
+/// should be built.
+class CompilationOptions {
+  /// Creates a [CompilationOptions] object.
+  const CompilationOptions({
+    this.renderer = WebRenderer.canvaskit,
+    this.useWasm = false,
+  });
+
+  /// The renderer to use for the build.
+  final WebRenderer renderer;
+
+  /// Whether to build the app with dart2wasm.
+  final bool useWasm;
+
+  @override
+  String toString() {
+    return '(renderer: ${renderer.name}, compiler: ${useWasm ? 'dart2wasm' : 'dart2js'})';
+  }
+}
+
+/// The possible types of web renderers Flutter can build for.
+enum WebRenderer {
+  /// The HTML web renderer.
+  html,
+
+  /// The CanvasKit web renderer.
+  canvaskit,
+
+  /// The SKIA Wasm web renderer.
+  skwasm,
+}

packages/web_benchmarks/lib/src/runner.dart

@@ -18,6 +18,7 @@ import 'package:shelf_static/shelf_static.dart';
 import 'benchmark_result.dart';
 import 'browser.dart';
 import 'common.dart';
+import 'compilation_options.dart';
 
 /// The default port number used by the local benchmark server.
 const int defaultBenchmarkServerPort = 9999;
@@ -50,11 +51,11 @@ class BenchmarkServer {
   BenchmarkServer({
     required this.benchmarkAppDirectory,
     required this.entryPoint,
-    required this.useCanvasKit,
     required this.benchmarkServerPort,
     required this.chromeDebugPort,
     required this.headless,
     required this.treeShakeIcons,
+    this.compilationOptions = const CompilationOptions(),
     this.initialPage = defaultInitialPage,
   });
 
@@ -72,8 +73,8 @@ class BenchmarkServer {
   /// the app.
   final String entryPoint;
 
-  /// Whether to build the app in CanvasKit mode.
-  final bool useCanvasKit;
+  /// The compilation options to use for building the benchmark web app.
+  final CompilationOptions compilationOptions;
 
   /// The port this benchmark server serves the app on.
   final int benchmarkServerPort;
@@ -109,13 +110,20 @@ class BenchmarkServer {
           "flutter executable is not runnable. Make sure it's in the PATH.");
     }
 
+    final DateTime startTime = DateTime.now();
+    print('Building Flutter web app $compilationOptions...');
     final io.ProcessResult buildResult = await _processManager.run(
       <String>[
         'flutter',
         'build',
         'web',
+        if (compilationOptions.useWasm) ...<String>[
+          '--wasm',
+          '--wasm-opt=debug',
+          '--omit-type-checks',
+        ],
+        '--web-renderer=${compilationOptions.renderer.name}',
         '--dart-define=FLUTTER_WEB_ENABLE_PROFILING=true',
-        if (useCanvasKit) '--dart-define=FLUTTER_WEB_USE_SKIA=true',
         if (!treeShakeIcons) '--no-tree-shake-icons',
         '--profile',
         '-t',
@@ -124,6 +132,12 @@ class BenchmarkServer {
       workingDirectory: benchmarkAppDirectory.path,
     );
 
+    final int buildTime = Duration(
+      milliseconds: DateTime.now().millisecondsSinceEpoch -
+          startTime.millisecondsSinceEpoch,
+    ).inSeconds;
+    print('Build took ${buildTime}s to complete.');
+
     if (buildResult.exitCode != 0) {
       io.stderr.writeln(buildResult.stdout);
       io.stderr.writeln(buildResult.stderr);

packages/web_benchmarks/pubspec.yaml

@@ -2,7 +2,7 @@ name: web_benchmarks
 description: A benchmark harness for performance-testing Flutter apps in Chrome.
 repository: https://github.com/flutter/packages/tree/main/packages/web_benchmarks
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+web_benchmarks%22
-version: 0.1.0+11
+version: 1.0.0
 
 environment:
   sdk: ">=3.2.0 <4.0.0"

packages/web_benchmarks/testing/web_benchmarks_test.dart

@@ -25,19 +25,28 @@ Future<void> main() async {
       initialPage: 'index.html#about',
     );
   }, timeout: Timeout.none);
+
+  test('Can run a web benchmark with wasm', () async {
+    await _runBenchmarks(
+      benchmarkNames: <String>['simple'],
+      entryPoint: 'lib/benchmarks/runner_simple.dart',
+      compilationOptions: const CompilationOptions(useWasm: true),
+    );
+  }, timeout: Timeout.none);
 }
 
 Future<void> _runBenchmarks({
   required List<String> benchmarkNames,
   required String entryPoint,
   String initialPage = defaultInitialPage,
+  CompilationOptions compilationOptions = const CompilationOptions(),
 }) async {
   final BenchmarkResults taskResult = await serveWebBenchmark(
     benchmarkAppDirectory: Directory('testing/test_app'),
     entryPoint: entryPoint,
-    useCanvasKit: false,
     treeShakeIcons: false,
     initialPage: initialPage,
+    compilationOptions: compilationOptions,
   );
 
   for (final String benchmarkName in benchmarkNames) {