[flutter_tools] do not require a dependency on devtools server (#66842)

Re-arrange the implementation of the devtools launcher so that google3 is not required to depend on any devtools packages. Also renames the build_runner folders to isolated to better clarify their intention.

packages/flutter_tools/lib/executable.dart

@@ -9,13 +9,7 @@ import 'src/base/context.dart';
 import 'src/base/io.dart';
 import 'src/base/logger.dart';
 import 'src/base/template.dart';
-// The build_runner code generation is provided here to make it easier to
-// avoid introducing the dependency into google3. Not all build* packages
-// are synced internally.
 import 'src/base/terminal.dart';
-import 'src/build_runner/mustache_template.dart';
-import 'src/build_runner/resident_web_runner.dart';
-import 'src/build_runner/web_compilation_delegate.dart';
 import 'src/commands/analyze.dart';
 import 'src/commands/assemble.dart';
 import 'src/commands/attach.dart';
@@ -51,6 +45,12 @@ import 'src/commands/upgrade.dart';
 import 'src/commands/version.dart';
 import 'src/features.dart';
 import 'src/globals.dart' as globals;
+// Files in `isolated` are intentionally excluded from google3 tooling.
+import 'src/isolated/devtools_launcher.dart';
+import 'src/isolated/mustache_template.dart';
+import 'src/isolated/resident_web_runner.dart';
+import 'src/isolated/web_compilation_delegate.dart';
+import 'src/resident_runner.dart';
 import 'src/runner/flutter_command.dart';
 import 'src/web/compile.dart';
 import 'src/web/web_runner.dart';
@@ -136,6 +136,9 @@ Future<void> main(List<String> args) async {
        WebRunnerFactory: () => DwdsWebRunnerFactory(),
        // The mustache dependency is different in google3
        TemplateRenderer: () => const MustacheTemplateRenderer(),
+       // The devtools launcher is not supported in google3 because it depends on
+       // devtools source code.
+       DevtoolsLauncher: () => DevtoolsServerLauncher(logger: globals.logger),
        Logger: () {
         final LoggerFactory loggerFactory = LoggerFactory(
           outputPreferences: globals.outputPreferences,
@@ -153,7 +156,6 @@ Future<void> main(List<String> args) async {
      });
 }
 
-
 /// An abstraction for instantiation of the correct logger type.
 ///
 /// Our logger class hierarchy and runtime requirements are overly complicated.

packages/flutter_tools/lib/src/isolated/devtools_launcher.dart

@@ -0,0 +1,61 @@
+// Copyright 2014 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.
+
+import 'package:devtools_server/devtools_server.dart' as devtools_server;
+import 'package:meta/meta.dart';
+
+import '../base/io.dart' as io;
+import '../base/logger.dart';
+import '../resident_runner.dart';
+
+/// An implementation of the devtools launcher that uses the server package.
+///
+/// This is implemented in isolated to prevent the flutter_tool from needing
+/// a devtools dep in google3.
+class DevtoolsServerLauncher extends DevtoolsLauncher {
+  DevtoolsServerLauncher({
+    @required Logger logger,
+  }) : _logger = logger;
+
+  final Logger _logger;
+
+  io.HttpServer _devtoolsServer;
+
+  @override
+  Future<void> launch(Uri observatoryAddress) async {
+    try {
+      await serve();
+      await devtools_server.launchDevTools(
+        <String, dynamic>{
+          'reuseWindows': true,
+        },
+        observatoryAddress,
+        'http://${_devtoolsServer.address.host}:${_devtoolsServer.port}',
+        false,  // headless mode,
+        false,  // machine mode
+      );
+    } on Exception catch (e, st) {
+      _logger.printTrace('Failed to launch DevTools: $e\n$st');
+    }
+  }
+
+  @override
+  Future<DevToolsServerAddress> serve() async {
+    try {
+      _devtoolsServer ??= await devtools_server.serveDevTools(
+        enableStdinCommands: false,
+      );
+      return DevToolsServerAddress(_devtoolsServer.address.host, _devtoolsServer.port);
+    } on Exception catch (e, st) {
+      _logger.printTrace('Failed to serve DevTools: $e\n$st');
+      return null;
+    }
+  }
+
+  @override
+  Future<void> close() async {
+    await _devtoolsServer?.close();
+    _devtoolsServer = null;
+  }
+}

packages/flutter_tools/lib/src/resident_runner.dart

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:devtools_server/devtools_server.dart' as devtools_server;
 import 'package:meta/meta.dart';
 import 'package:package_config/package_config.dart';
 import 'package:vm_service/vm_service.dart' as vm_service;
@@ -1703,43 +1702,15 @@ String nextPlatform(String currentPlatform, FeatureFlags featureFlags) {
   }
 }
 
-class DevtoolsLauncher {
-  io.HttpServer _devtoolsServer;
-  Future<void> launch(Uri observatoryAddress) async {
-    try {
-      await serve();
-      await devtools_server.launchDevTools(
-        <String, dynamic>{
-          'reuseWindows': true,
-        },
-        observatoryAddress,
-        'http://${_devtoolsServer.address.host}:${_devtoolsServer.port}',
-        false,  // headless mode,
-        false,  // machine mode
-      );
-    } on Exception catch (e, st) {
-      globals.printTrace('Failed to launch DevTools: $e\n$st');
-    }
-  }
+/// A launcher for the devtools debugger and analysis tool.
+abstract class DevtoolsLauncher {
+  Future<void> launch(Uri observatoryAddress);
 
-  Future<DevToolsServerAddress> serve() async {
-    try {
-      _devtoolsServer ??= await devtools_server.serveDevTools(
-        enableStdinCommands: false,
-      );
-      return DevToolsServerAddress(_devtoolsServer.address.host, _devtoolsServer.port);
-    } on Exception catch (e, st) {
-      globals.printTrace('Failed to serve DevTools: $e\n$st');
-      return null;
-    }
-  }
+  Future<DevToolsServerAddress> serve();
 
-  Future<void> close() async {
-    await _devtoolsServer?.close();
-    _devtoolsServer = null;
-  }
+  Future<void> close();
 
-  static DevtoolsLauncher get instance => context.get<DevtoolsLauncher>() ?? DevtoolsLauncher();
+  static DevtoolsLauncher get instance => context.get<DevtoolsLauncher>();
 }
 
 class DevToolsServerAddress {

packages/flutter_tools/test/general.shard/resident_web_runner_cold_test.dart

@@ -10,8 +10,8 @@ import 'package:flutter_tools/src/base/logger.dart';
 import 'package:flutter_tools/src/base/platform.dart';
 import 'package:flutter_tools/src/base/terminal.dart';
 import 'package:flutter_tools/src/build_info.dart';
-import 'package:flutter_tools/src/build_runner/devfs_web.dart';
-import 'package:flutter_tools/src/build_runner/resident_web_runner.dart';
+import 'package:flutter_tools/src/isolated/devfs_web.dart';
+import 'package:flutter_tools/src/isolated/resident_web_runner.dart';
 import 'package:flutter_tools/src/build_system/build_system.dart';
 import 'package:flutter_tools/src/dart/pub.dart';
 import 'package:flutter_tools/src/device.dart';

packages/flutter_tools/test/general.shard/resident_web_runner_test.dart

@@ -15,8 +15,8 @@ import 'package:flutter_tools/src/base/logger.dart';
 import 'package:flutter_tools/src/base/platform.dart';
 import 'package:flutter_tools/src/base/terminal.dart';
 import 'package:flutter_tools/src/build_info.dart';
-import 'package:flutter_tools/src/build_runner/devfs_web.dart';
-import 'package:flutter_tools/src/build_runner/resident_web_runner.dart';
+import 'package:flutter_tools/src/isolated/devfs_web.dart';
+import 'package:flutter_tools/src/isolated/resident_web_runner.dart';
 import 'package:flutter_tools/src/compile.dart';
 import 'package:flutter_tools/src/dart/pub.dart';
 import 'package:flutter_tools/src/devfs.dart';

packages/flutter_tools/test/general.shard/web/devfs_web_test.dart

@@ -10,7 +10,7 @@ import 'package:flutter_tools/src/base/file_system.dart';
 import 'package:flutter_tools/src/base/io.dart';
 import 'package:flutter_tools/src/base/platform.dart';
 import 'package:flutter_tools/src/build_info.dart';
-import 'package:flutter_tools/src/build_runner/devfs_web.dart';
+import 'package:flutter_tools/src/isolated/devfs_web.dart';
 import 'package:flutter_tools/src/compile.dart';
 import 'package:flutter_tools/src/convert.dart';
 import 'package:flutter_tools/src/globals.dart' as globals;

packages/flutter_tools/test/general.shard/web/web_asset_server_test.dart

@@ -6,7 +6,7 @@ import 'package:file/memory.dart';
 import 'package:flutter_tools/src/base/file_system.dart';
 import 'package:flutter_tools/src/base/io.dart';
 import 'package:flutter_tools/src/base/platform.dart';
-import 'package:flutter_tools/src/build_runner/devfs_web.dart';
+import 'package:flutter_tools/src/isolated/devfs_web.dart';
 import 'package:shelf/shelf.dart';
 
 import '../../src/common.dart';

packages/flutter_tools/test/general.shard/web/web_expression_compiler_test.dart

@@ -4,7 +4,7 @@
 
 import 'package:dwds/dwds.dart';
 import 'package:flutter_tools/src/compile.dart';
-import 'package:flutter_tools/src/build_runner/devfs_web.dart';
+import 'package:flutter_tools/src/isolated/devfs_web.dart';
 import 'package:matcher/matcher.dart';
 import 'package:mockito/mockito.dart';
 import 'package:flutter_tools/src/globals.dart' as globals;

packages/flutter_tools/test/integration.shard/forbidden_imports_test.dart

@@ -86,7 +86,6 @@ void main() {
 
   test('no unauthorized imports of test_api', () {
     final List<String> allowedPaths = <String>[
-      fileSystem.path.join(flutterTools, 'lib', 'src', 'build_runner', 'build_script.dart'),
       fileSystem.path.join(flutterTools, 'lib', 'src', 'test', 'flutter_platform.dart'),
       fileSystem.path.join(flutterTools, 'lib', 'src', 'test', 'flutter_web_platform.dart'),
       fileSystem.path.join(flutterTools, 'lib', 'src', 'test', 'test_wrapper.dart'),
@@ -113,7 +112,7 @@ void main() {
 
   test('no unauthorized imports of package:path', () {
     final List<String> allowedPath = <String>[
-      fileSystem.path.join(flutterTools, 'lib', 'src', 'build_runner', 'web_compilation_delegate.dart'),
+      fileSystem.path.join(flutterTools, 'lib', 'src', 'isolated', 'web_compilation_delegate.dart'),
       fileSystem.path.join(flutterTools, 'test', 'general.shard', 'platform_plugins_test.dart'),
     ];
     for (final String dirName in <String>['lib', 'bin', 'test']) {
@@ -181,10 +180,10 @@ void main() {
     }
   });
 
-  test('no unauthorized imports of build_runner or dwds', () {
+  test('no unauthorized imports of build_runner/dwds/devtools', () {
     final List<String> allowedPaths = <String>[
-      fileSystem.path.join(flutterTools, 'test', 'src', 'build_runner'),
-      fileSystem.path.join(flutterTools, 'lib', 'src', 'build_runner'),
+      fileSystem.path.join(flutterTools, 'test', 'src', 'isolated'),
+      fileSystem.path.join(flutterTools, 'lib', 'src', 'isolated'),
       fileSystem.path.join(flutterTools, 'lib', 'executable.dart'),
       fileSystem.path.join(flutterTools, 'lib', 'devfs_web.dart'),
       fileSystem.path.join(flutterTools, 'lib', 'resident_web_runner.dart'),
@@ -203,9 +202,10 @@ void main() {
               line.startsWith(RegExp(r'import.*package:build_runner/build_runner.dart')) ||
               line.startsWith(RegExp(r'import.*package:build_config/build_config.dart')) ||
               line.startsWith(RegExp(r'import.*dwds:*.dart')) ||
+              line.startsWith(RegExp(r'import.*devtools_server:*.dart')) ||
               line.startsWith(RegExp(r'import.*build_runner/.*.dart'))) {
             final String relativePath = fileSystem.path.relative(file.path, from:flutterTools);
-            fail('$relativePath imports a build_runner package');
+            fail('$relativePath imports a build_runner/dwds/devtools package');
           }
         }
       }

packages/flutter_tools/test/src/context.dart

@@ -17,7 +17,7 @@ import 'package:flutter_tools/src/base/signals.dart';
 import 'package:flutter_tools/src/base/template.dart';
 import 'package:flutter_tools/src/base/terminal.dart';
 import 'package:flutter_tools/src/base/time.dart';
-import 'package:flutter_tools/src/build_runner/mustache_template.dart';
+import 'package:flutter_tools/src/isolated/mustache_template.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/context_runner.dart';
 import 'package:flutter_tools/src/dart/pub.dart';