Migrate hot reload tests to Dart 2 (#21290)

packages/flutter_tools/lib/src/resident_runner.dart

@@ -47,9 +47,10 @@ class FlutterDevice {
     this.dillOutputPath,
     this.fileSystemRoots,
     this.fileSystemScheme,
+    ResidentCompiler generator,
   }) {
     if (previewDart2) {
-      generator = new ResidentCompiler(
+      this.generator = generator ?? new ResidentCompiler(
         artifacts.getArtifactPath(Artifact.flutterPatchedSdkPath),
         trackWidgetCreation: trackWidgetCreation,
         fileSystemRoots: fileSystemRoots, fileSystemScheme: fileSystemScheme

packages/flutter_tools/test/hot_test.dart

@@ -4,6 +4,7 @@
 
 import 'dart:async';
 
+import 'package:flutter_tools/src/artifacts.dart';
 import 'package:flutter_tools/src/device.dart';
 import 'package:flutter_tools/src/resident_runner.dart';
 import 'package:flutter_tools/src/run_hot.dart';
@@ -12,6 +13,7 @@ import 'package:mockito/mockito.dart';
 
 import 'src/common.dart';
 import 'src/context.dart';
+import 'src/mocks.dart';
 
 void main() {
   group('validateReloadReport', () {
@@ -91,34 +93,41 @@ void main() {
   });
 
   group('hotRestart', () {
-    final List<FlutterDevice> devices = <FlutterDevice>[];
+    final MockResidentCompiler residentCompiler = new MockResidentCompiler();
+    MockLocalEngineArtifacts mockArtifacts;
 
     setUp(() {
-      devices.add(new FlutterDevice(new MockDevice(),
-          previewDart2: false, trackWidgetCreation: false));
+      mockArtifacts = new MockLocalEngineArtifacts();
+      when(mockArtifacts.getArtifactPath(Artifact.flutterPatchedSdkPath)).thenReturn('some/path');
     });
 
     testUsingContext('no setup', () async {
-      expect((await new HotRunner(devices).restart(fullRestart: true)).isOk,
-          true);
+      final List<FlutterDevice> devices = <FlutterDevice>[new FlutterDevice(new MockDevice(), generator: residentCompiler, trackWidgetCreation: false, previewDart2: true)];
+      expect((await new HotRunner(devices).restart(fullRestart: true)).isOk, true);
+    }, overrides: <Type, Generator>{
+      Artifacts: () => mockArtifacts,
     });
 
     testUsingContext('setup function succeeds', () async {
-      expect((await new HotRunner(devices).restart(fullRestart: true)).isOk,
-          true);
+      final List<FlutterDevice> devices = <FlutterDevice>[new FlutterDevice(new MockDevice(), generator: residentCompiler, trackWidgetCreation: false, previewDart2: true)];
+      expect((await new HotRunner(devices).restart(fullRestart: true)).isOk, true);
     }, overrides: <Type, Generator>{
+      Artifacts: () => mockArtifacts,
       HotRunnerConfig: () => new TestHotRunnerConfig(successfulSetup: true),
     });
 
     testUsingContext('setup function fails', () async {
-      expect((await new HotRunner(devices).restart(fullRestart: true)).isOk,
-          false);
+      final List<FlutterDevice> devices = <FlutterDevice>[new FlutterDevice(new MockDevice(), generator: residentCompiler, trackWidgetCreation: false, previewDart2: true)];
+      expect((await new HotRunner(devices).restart(fullRestart: true)).isOk, false);
     }, overrides: <Type, Generator>{
+      Artifacts: () => mockArtifacts,
       HotRunnerConfig: () => new TestHotRunnerConfig(successfulSetup: false),
     });
   });
 }
 
+class MockLocalEngineArtifacts extends Mock implements LocalEngineArtifacts {}
+
 class MockDevice extends Mock implements Device {
   MockDevice() {
     when(isSupported()).thenReturn(true);