Add support for expression compilation when debugging integration tests

packages/flutter_tools/lib/src/test/flutter_platform.dart

@@ -418,6 +418,7 @@ class FlutterPlatform extends PlatformPlugin {
         debuggingOptions: debuggingOptions,
         device: integrationTestDevice!,
         userIdentifier: integrationTestUserIdentifier,
+        compileExpression: _compileExpressionService
       );
     }
     return FlutterTesterTestDevice(
@@ -457,21 +458,22 @@ class FlutterPlatform extends PlatformPlugin {
         controllerSinkClosed = true;
       }));
 
+      // When start paused is specified, it means that the user is likely
+      // running this with a debugger attached. Initialize the resident
+      // compiler in this case.
+      if (debuggingOptions.startPaused) {
+        compiler ??= TestCompiler(debuggingOptions.buildInfo, flutterProject, precompiledDillPath: precompiledDillPath, testTimeRecorder: testTimeRecorder);
+        final Uri testUri = globals.fs.file(testPath).uri;
+        // Trigger a compilation to initialize the resident compiler.
+        unawaited(compiler!.compile(testUri));
+      }
+
       // If a kernel file is given, then use that to launch the test.
       // If mapping is provided, look kernel file from mapping.
       // If all fails, create a "listener" dart that invokes actual test.
       String? mainDart;
       if (precompiledDillPath != null) {
         mainDart = precompiledDillPath;
-        // When start paused is specified, it means that the user is likely
-        // running this with a debugger attached. Initialize the resident
-        // compiler in this case.
-        if (debuggingOptions.startPaused) {
-          compiler ??= TestCompiler(debuggingOptions.buildInfo, flutterProject, precompiledDillPath: precompiledDillPath, testTimeRecorder: testTimeRecorder);
-          final Uri testUri = globals.fs.file(testPath).uri;
-          // Trigger a compilation to initialize the resident compiler.
-          unawaited(compiler!.compile(testUri));
-        }
       } else if (precompiledDillFiles != null) {
         mainDart = precompiledDillFiles![testPath];
       } else {

packages/flutter_tools/lib/src/test/integration_test_device.dart

@@ -24,12 +24,14 @@ class IntegrationTestTestDevice implements TestDevice {
     required this.device,
     required this.debuggingOptions,
     required this.userIdentifier,
+    required this.compileExpression,
   });
 
   final int id;
   final Device device;
   final DebuggingOptions debuggingOptions;
   final String? userIdentifier;
+  final CompileExpression? compileExpression;
 
   ApplicationPackage? _applicationPackage;
   final Completer<void> _finished = Completer<void>();
@@ -70,7 +72,11 @@ class IntegrationTestTestDevice implements TestDevice {
     _gotProcessObservatoryUri.complete(observatoryUri);
 
     globals.printTrace('test $id: Connecting to vm service');
-    final FlutterVmService vmService = await connectToVmService(observatoryUri, logger: globals.logger).timeout(
+    final FlutterVmService vmService = await connectToVmService(
+      observatoryUri,
+      logger: globals.logger,
+      compileExpression: compileExpression,
+    ).timeout(
       const Duration(seconds: 5),
       onTimeout: () => throw TimeoutException('Connecting to the VM Service timed out.'),
     );

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

@@ -77,6 +77,7 @@ void main() {
         BuildInfo.debug,
       ),
       userIdentifier: '',
+      compileExpression: null,
     );
 
     fakeVmServiceHost = FakeVmServiceHost(requests: <VmServiceExpectation>[
@@ -173,6 +174,7 @@ void main() {
         BuildInfo.debug,
       ),
       userIdentifier: '',
+      compileExpression: null,
     );
 
     expect(() => testDevice.start('entrypointPath'), throwsA(isA<TestDeviceException>()));
@@ -201,6 +203,7 @@ void main() {
         BuildInfo.debug,
       ),
       userIdentifier: '',
+      compileExpression: null,
     );
 
     expect(() => testDevice.start('entrypointPath'), throwsA(isA<TestDeviceException>()));

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

@@ -8,6 +8,7 @@ import 'package:vm_service/vm_service.dart';
 
 import '../src/common.dart';
 import 'test_data/basic_project.dart';
+import 'test_data/integration_tests_project.dart';
 import 'test_data/tests_project.dart';
 import 'test_driver.dart';
 import 'test_utils.dart';
@@ -141,6 +142,37 @@ void batch2() {
   });
 }
 
+void batch3() {
+  final IntegrationTestsProject project = IntegrationTestsProject();
+  late Directory tempDir;
+  late FlutterTestTestDriver flutter;
+
+  Future<void> initProject() async {
+    tempDir = createResolvedTempDirectorySync('integration_test_expression_eval_test.');
+    await project.setUpIn(tempDir);
+    flutter = FlutterTestTestDriver(tempDir);
+  }
+
+  Future<void> cleanProject() async {
+    await flutter.waitForCompletion();
+    tryToDelete(tempDir);
+  }
+
+  testWithoutContext('flutter integration test expression evaluation - can evaluate expressions in a test', () async {
+    await initProject();
+    await flutter.test(
+      deviceId: 'flutter-tester',
+      testFile: project.testFilePath,
+      withDebugger: true,
+      beforeStart: () => flutter.addBreakpoint(project.breakpointUri, project.breakpointLine),
+    );
+    await flutter.waitForPause();
+    await evaluateTrivialExpressions(flutter);
+    await cleanProject();
+  });
+
+}
+
 Future<void> evaluateTrivialExpressions(FlutterTestDriver flutter) async {
   ObjRef res;
 
@@ -189,4 +221,5 @@ void expectValue(ObjRef result, String message) {
 void main() {
   batch1();
   batch2();
+  batch3();
 }

packages/flutter_tools/test/integration.shard/test_data/integration_tests_project.dart

@@ -58,11 +58,11 @@ class IntegrationTestsProject extends Project implements TestsProject {
   String get testFilePath => fileSystem.path.join(dir.path, 'integration_test', 'app_test.dart');
 
   @override
-  Uri get breakpointUri => throw UnimplementedError();
+  Uri get breakpointUri => Uri.file(testFilePath);
 
   @override
   Uri get breakpointAppUri => throw UnimplementedError();
 
   @override
-  int get breakpointLine => throw UnimplementedError();
+  int get breakpointLine => lineContaining(testContent, '// BREAKPOINT');
 }

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

@@ -763,6 +763,7 @@ class FlutterTestTestDriver extends FlutterTestDriver {
 
   Future<void> test({
     String testFile = 'test/test.dart',
+    String? deviceId,
     bool withDebugger = false,
     bool pauseOnExceptions = false,
     bool coverage = false,
@@ -775,6 +776,8 @@ class FlutterTestTestDriver extends FlutterTestDriver {
       '--machine',
       if (coverage)
         '--coverage',
+      if (deviceId != null)
+        ...<String>['-d', deviceId],
     ], script: testFile, withDebugger: withDebugger, pauseOnExceptions: pauseOnExceptions, beforeStart: beforeStart);
   }