From f5080bedb38c77bd99b5caa0bc012007ab7158e3 Mon Sep 17 00:00:00 2001
From: Derek Xu <derekx@google.com>
Date: Tue, 11 Jul 2023 18:41:04 +0000
Subject: [PATCH] [VM/Debugger] Fix behaviour of
 ActivationFrame::EvaluateCompiledExpression when paused inside a closure

TEST=pkg/vm_service/test/evaluate_inside_closures_test.dart, pkg tryjob

Fixes: https://github.com/dart-lang/sdk/issues/52430
Change-Id: I72b755d31614c7c56c504130656c3668d8b7e72b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/313001
Commit-Queue: Derek Xu <derekx@google.com>
Reviewed-by: Ben Konyi <bkonyi@google.com>
---
 .../test/evaluate_inside_closures_test.dart   | 92 +++++++++++++++++++
 runtime/vm/debugger.cc                        |  5 +-
 2 files changed, 96 insertions(+), 1 deletion(-)
 create mode 100644 pkg/vm_service/test/evaluate_inside_closures_test.dart

diff --git a/pkg/vm_service/test/evaluate_inside_closures_test.dart b/pkg/vm_service/test/evaluate_inside_closures_test.dart
new file mode 100644
index 000000000000..434775a8fb3c
--- /dev/null
+++ b/pkg/vm_service/test/evaluate_inside_closures_test.dart
@@ -0,0 +1,92 @@
+// Copyright (c) 2023, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Regression test for https://dartbug.com/52430.
+
+import 'dart:developer';
+
+import 'package:test/test.dart';
+import 'package:vm_service/vm_service.dart';
+
+import 'common/service_test_common.dart';
+import 'common/test_helper.dart';
+
+class C {
+  static int staticField = 12;
+  int instanceField = 34;
+
+  static void staticMethod() {
+    ((int x) {
+      debugger();
+    })(56);
+  }
+
+  void instanceMethod() {
+    ((int y) {
+      debugger();
+    })(78);
+  }
+}
+
+testMain() {
+  C c = C();
+  C.staticMethod();
+  c.instanceMethod();
+}
+
+final tests = <IsolateTest>[
+  hasStoppedAtBreakpoint,
+  stoppedAtLine(21),
+  (VmService service, IsolateRef isolateRef) async {
+    final isolateId = isolateRef.id!;
+
+    final xRef =
+        await service.evaluateInFrame(isolateId, 0, 'x') as InstanceRef;
+    expect(xRef.valueAsString, '56');
+
+    InstanceRef staticFieldRef = await service.evaluateInFrame(
+        isolateId, 0, 'staticField += 1') as InstanceRef;
+    expect(staticFieldRef.valueAsString, '13');
+    staticFieldRef = await service.evaluateInFrame(isolateId, 0, 'staticField')
+        as InstanceRef;
+    expect(staticFieldRef.valueAsString, '13');
+
+    // Evaluating 'instanceField' should fail since we are paused in the context
+    // of a static method.
+    try {
+      await service.evaluateInFrame(isolateId, 0, 'instanceField');
+      fail('Expected RPCError');
+    } catch (e) {
+      final rpcError = e as RPCError;
+      expect(rpcError.code, RPCErrorKind.kExpressionCompilationError.code);
+    }
+  },
+  resumeIsolate,
+  stoppedAtLine(27),
+  (VmService service, IsolateRef isolateRef) async {
+    final isolateId = isolateRef.id!;
+
+    final yRef =
+        await service.evaluateInFrame(isolateId, 0, 'y') as InstanceRef;
+    expect(yRef.valueAsString, '78');
+
+    InstanceRef staticFieldRef = await service.evaluateInFrame(
+        isolateId, 0, 'staticField += 1') as InstanceRef;
+    expect(staticFieldRef.valueAsString, '14');
+    staticFieldRef = await service.evaluateInFrame(isolateId, 0, 'staticField')
+        as InstanceRef;
+    expect(staticFieldRef.valueAsString, '14');
+
+    InstanceRef instanceFieldRef = await service.evaluateInFrame(
+        isolateId, 0, 'instanceField += 1') as InstanceRef;
+    expect(instanceFieldRef.valueAsString, '35');
+    instanceFieldRef = await service.evaluateInFrame(
+        isolateId, 0, 'instanceField') as InstanceRef;
+    expect(instanceFieldRef.valueAsString, '35');
+  }
+];
+
+main([args = const <String>[]]) async =>
+    runIsolateTests(args, tests, 'evaluate_inside_closures_test.dart',
+        testeeConcurrent: testMain);
diff --git a/runtime/vm/debugger.cc b/runtime/vm/debugger.cc
index 5b7c00a2f733..64d965ecb76f 100644
--- a/runtime/vm/debugger.cc
+++ b/runtime/vm/debugger.cc
@@ -1055,7 +1055,10 @@ ObjectPtr ActivationFrame::EvaluateCompiledExpression(
     const Array& type_definitions,
     const Array& arguments,
     const TypeArguments& type_arguments) {
-  if (function().is_static()) {
+  if (function().IsClosureFunction()) {
+    return Library::Handle(Library()).EvaluateCompiledExpression(
+        kernel_buffer, type_definitions, arguments, type_arguments);
+  } else if (function().is_static()) {
     const Class& cls = Class::Handle(function().Owner());
     return cls.EvaluateCompiledExpression(kernel_buffer, type_definitions,
                                           arguments, type_arguments);