1 files changed, 50 insertions, 0 deletions
diff --git a/dom/base/TestUtils.cpp b/dom/base/TestUtils.cpp
new file mode 100644
index 0000000000..6e4803d8ab
--- /dev/null
+++ b/dom/base/TestUtils.cpp
@@ -0,0 +1,50 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/TestUtils.h"
+#include "mozilla/dom/TestUtilsBinding.h"
+
+#include "mozilla/ErrorResult.h"
+#include "mozilla/dom/Promise.h"
+#include "mozilla/dom/WorkerCommon.h"
+#include "mozilla/dom/WorkerPrivate.h"
+#include "nsJSEnvironment.h"
+#include "xpcpublic.h"
+
+namespace mozilla::dom {
+
+already_AddRefed<Promise> TestUtils::Gc(const GlobalObject& aGlobal,
+                                        ErrorResult& aRv) {
+  nsCOMPtr<nsIGlobalObject> global = do_QueryInterface(aGlobal.GetAsSupports());
+  RefPtr<Promise> promise = Promise::Create(global, aRv);
+  if (NS_WARN_IF(aRv.Failed())) {
+    return nullptr;
+  }
+
+  // TODO(krosylight): Ideally we could use nsJSContext::IncrementalGC to make
+  // it actually async, but that's not required right now.
+
+  NS_DispatchToCurrentThread(
+      NS_NewCancelableRunnableFunction("TestUtils::Gc", [promise] {
+        if (NS_IsMainThread()) {
+          nsJSContext::GarbageCollectNow(JS::GCReason::DOM_TESTUTILS,
+                                         nsJSContext::NonShrinkingGC);
+          nsJSContext::CycleCollectNow(CCReason::API);
+        } else {
+          WorkerPrivate* workerPrivate = GetCurrentThreadWorkerPrivate();
+          workerPrivate->GarbageCollectInternal(workerPrivate->GetJSContext(),
+                                                false /* shrinking */,
+                                                false /* collect children */);
+          workerPrivate->CycleCollectInternal(false);
+        }
+
+        promise->MaybeResolveWithUndefined();
+      }));
+
+  return promise.forget();
+}
+
+}  // namespace mozilla::dom