[test] Fix missing GC in SingleThreadedDefaultPlatformTest

Bug: v8:12781
Change-Id: I7dfddd886571a16a180bffb8f9fc7a946d5667bc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3576113
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79851}

test/unittests/libplatform/single-threaded-default-platform-unittest.cc

@@ -34,21 +34,20 @@ class WithSingleThreadedDefaultPlatformMixin : public TMixin {
 };
 
 class SingleThreadedDefaultPlatformTest
-    : public WithContextMixin<                             //
-          WithIsolateScopeMixin<                           //
+    : public WithIsolateScopeMixin<                    //
           WithIsolateMixin<                            //
               WithSingleThreadedDefaultPlatformMixin<  //
-                      ::testing::Test>>>> {
+                  ::testing::Test>>> {
  public:
   static void SetUpTestSuite() {
     CHECK_NULL(save_flags_);
     save_flags_ = new i::SaveFlags();
     v8::V8::SetFlagsFromString("--single-threaded");
-    WithContextMixin::SetUpTestSuite();
+    WithIsolateScopeMixin::SetUpTestSuite();
   }
 
   static void TearDownTestSuite() {
-    WithContextMixin::TearDownTestSuite();
+    WithIsolateScopeMixin::TearDownTestSuite();
     CHECK_NOT_NULL(save_flags_);
     delete save_flags_;
     save_flags_ = nullptr;
@@ -62,6 +61,11 @@ class SingleThreadedDefaultPlatformTest
 i::SaveFlags* SingleThreadedDefaultPlatformTest::save_flags_;
 
 TEST_F(SingleThreadedDefaultPlatformTest, SingleThreadedDefaultPlatform) {
+  {
+    i::HandleScope scope(i_isolate());
+    v8::Local<Context> env = Context::New(isolate());
+    v8::Context::Scope context_scope(env);
+
     RunJS(
         "function f() {"
         "  for (let i = 0; i < 10; i++)"
@@ -69,6 +73,10 @@ TEST_F(SingleThreadedDefaultPlatformTest, SingleThreadedDefaultPlatform) {
         "  return 0;"
         "}"
         "f();");
+  }
+
+  CollectGarbage(i::NEW_SPACE);
+  CollectAllAvailableGarbage();
 }
 
 }  // namespace v8

test/unittests/test-utils.h

@@ -101,7 +101,48 @@ class WithIsolateScopeMixin : public TMixin {
     return reinterpret_cast<v8::internal::Isolate*>(this->v8_isolate());
   }
 
+  Local<Value> RunJS(const char* source) {
+    return RunJS(
+        v8::String::NewFromUtf8(this->v8_isolate(), source).ToLocalChecked());
+  }
+
+  Local<Value> RunJS(v8::String::ExternalOneByteStringResource* source) {
+    return RunJS(v8::String::NewExternalOneByte(this->v8_isolate(), source)
+                     .ToLocalChecked());
+  }
+
+  void CollectGarbage(i::AllocationSpace space) {
+    i_isolate()->heap()->CollectGarbage(space,
+                                        i::GarbageCollectionReason::kTesting);
+  }
+
+  void CollectAllGarbage() {
+    i_isolate()->heap()->CollectAllGarbage(
+        i::Heap::kNoGCFlags, i::GarbageCollectionReason::kTesting);
+  }
+
+  void CollectAllAvailableGarbage() {
+    i_isolate()->heap()->CollectAllAvailableGarbage(
+        i::GarbageCollectionReason::kTesting);
+  }
+
+  void PreciseCollectAllGarbage() {
+    i_isolate()->heap()->PreciseCollectAllGarbage(
+        i::Heap::kNoGCFlags, i::GarbageCollectionReason::kTesting);
+  }
+
+  v8::Local<v8::String> NewString(const char* string) {
+    return v8::String::NewFromUtf8(this->v8_isolate(), string).ToLocalChecked();
+  }
+
  private:
+  Local<Value> RunJS(Local<String> source) {
+    auto context = this->v8_isolate()->GetCurrentContext();
+    Local<Script> script =
+        v8::Script::Compile(context, source).ToLocalChecked();
+    return script->Run(context).ToLocalChecked();
+  }
+
   v8::Isolate::Scope isolate_scope_;
   v8::HandleScope handle_scope_;
 };
@@ -117,35 +158,14 @@ class WithContextMixin : public TMixin {
   const Local<Context>& context() const { return v8_context(); }
   const Local<Context>& v8_context() const { return context_; }
 
-  Local<Value> RunJS(const char* source) {
-    return RunJS(
-        v8::String::NewFromUtf8(this->v8_isolate(), source).ToLocalChecked());
-  }
-
-  Local<Value> RunJS(v8::String::ExternalOneByteStringResource* source) {
-    return RunJS(v8::String::NewExternalOneByte(this->v8_isolate(), source)
-                     .ToLocalChecked());
-  }
-
-  v8::Local<v8::String> NewString(const char* string) {
-    return v8::String::NewFromUtf8(this->v8_isolate(), string).ToLocalChecked();
-  }
-
   void SetGlobalProperty(const char* name, v8::Local<v8::Value> value) {
     CHECK(v8_context()
               ->Global()
-              ->Set(v8_context(), NewString(name), value)
+              ->Set(v8_context(), TMixin::NewString(name), value)
               .FromJust());
   }
 
  private:
-  Local<Value> RunJS(Local<String> source) {
-    auto context = this->v8_isolate()->GetCurrentContext();
-    Local<Script> script =
-        v8::Script::Compile(context, source).ToLocalChecked();
-    return script->Run(context).ToLocalChecked();
-  }
-
   v8::Local<v8::Context> context_;
   v8::Context::Scope context_scope_;
 };