Implement PaintWorkletGlobalScope#registerPaint() for the CSS Paint API

third_party/WebKit/Source/modules/csspaint/PaintWorkletTest.cpp

Index: third_party/WebKit/Source/modules/csspaint/PaintWorkletTest.cpp
diff --git a/third_party/WebKit/Source/modules/csspaint/PaintWorkletTest.cpp b/third_party/WebKit/Source/modules/csspaint/PaintWorkletTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..75dc44b2049fc255eee03d52f940c2e2798ed2f7
--- /dev/null
+++ b/third_party/WebKit/Source/modules/csspaint/PaintWorkletTest.cpp
@@ -0,0 +1,80 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "modules/csspaint/PaintWorklet.h"
+
+#include "bindings/core/v8/ScriptSourceCode.h"
+#include "bindings/core/v8/V8GCController.h"
+#include "bindings/core/v8/WorkerOrWorkletScriptController.h"
+#include "core/frame/LocalFrame.h"
+#include "core/testing/DummyPageHolder.h"
+#include "modules/csspaint/CSSPaintDefinition.h"
+#include "modules/csspaint/PaintWorkletGlobalScope.h"
+#include "modules/csspaint/WindowPaintWorklet.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "wtf/OwnPtr.h"
+
+namespace blink {
+
+namespace {
+
+static void clearHandle(const v8::WeakCallbackInfo<ScopedPersistent<v8::Function>>& data)
+{
+    data.GetParameter()->clear();
+}
+
+} // namespace
+
+class PaintWorkletTest : public testing::Test {
+public:
+    PaintWorkletTest()
+        : m_page(DummyPageHolder::create())
+    {
+    }
+
+    PaintWorklet* paintWorklet()
+    {
+        return WindowPaintWorklet::from(*m_page->frame().localDOMWindow()).paintWorklet(&m_page->document());
+    }
+
+protected:
+    OwnPtr<DummyPageHolder> m_page;
+};
+
+TEST_F(PaintWorkletTest, GarbageCollectionOfCSSPaintDefinition)
+{
+    PaintWorkletGlobalScope* globalScope = toPaintWorkletGlobalScope(paintWorklet()->workletGlobalScope());
+    globalScope->scriptController()->evaluate(ScriptSourceCode("registerPaint('foo', class { paint() { } });"));
+
+    CSSPaintDefinition* definition = globalScope->findDefinition("foo");
+    ASSERT(definition);
+
+    v8::Isolate* isolate = globalScope->scriptController()->getScriptState()->isolate();
+    ASSERT(isolate);
+
+    // Set our ScopedPersistent to the paint function, and make weak.
+    ScopedPersistent<v8::Function> handle;
+    {
+        v8::HandleScope handleScope(isolate);
+        handle.set(isolate, definition->paintFunctionForTesting(isolate));
+        handle.setWeak(&handle, clearHandle);
+    }
+    ASSERT(!handle.isEmpty());
+    ASSERT(handle.isWeak());
+
+    // Run a GC, persistent shouldn't have been collected yet.
+    Heap::collectGarbage(BlinkGC::NoHeapPointersOnStack, BlinkGC::GCWithSweep, BlinkGC::ForcedGC);

[haraken, 2016/04/01 00:16:06]

Use Heap::collectAllGarbage.

[ikilpatrick, 2016/04/01 03:08:43]

Done.

+    V8GCController::collectAllGarbageForTesting(isolate);
+    ASSERT(!handle.isEmpty());
+
+    // Delete the page & associated objects.
+    m_page.clear();
+
+    // Run a GC, the persistent should have been collected.
+    Heap::collectGarbage(BlinkGC::NoHeapPointersOnStack, BlinkGC::GCWithSweep, BlinkGC::ForcedGC);
+    V8GCController::collectAllGarbageForTesting(isolate);

[ikilpatrick, 2016/03/31 21:59:05]

Is assuming this OK?

At the moment in PaintWorkletGlobalScope m_paintDefinitions is a:
HeapHashMap<String, Member<CSSPaintDefinition>>

We explicitly need a Heap GC to run (clears the ScopedPersistents in
CSSPaintDefinition), then a V8 GC to run after.

Thoughts?

[haraken, 2016/04/01 00:16:06]

Looks good.

+    ASSERT(handle.isEmpty());
+}
+
+} // naespace blink