Source/WTF/wtf/CrossThreadCopier.cpp

/*
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 * Copyright (C) 2011-2016 Apple Inc. All rights reserved.
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#include "config.h"
#include <wtf/CrossThreadCopier.h>

namespace WTF {

// Test CrossThreadCopier using COMPILE_ASSERT.

// Verify that ThreadSafeRefCounted objects get handled correctly.
class CopierThreadSafeRefCountedTest : public ThreadSafeRefCounted<CopierThreadSafeRefCountedTest> {
};

COMPILE_ASSERT((std::is_same<
                    RefPtr<CopierThreadSafeRefCountedTest>,
                    CrossThreadCopier<RefPtr<CopierThreadSafeRefCountedTest>>::Type
                >::value),
                RefPtrTest);
COMPILE_ASSERT((std::is_same<
                    RefPtr<CopierThreadSafeRefCountedTest>,
                    CrossThreadCopier<CopierThreadSafeRefCountedTest*>::Type
                >::value),
                RawPointerTest);

// Add specializations for RefCounted types which will let us verify that no other template matches.
template<typename T> struct CrossThreadCopierBase<false, false, RefPtr<T>> {
    typedef int Type;
};

template<typename T> struct CrossThreadCopierBase<false, false, T*> {
    typedef int Type;
};

// Verify that RefCounted objects only match the above templates which expose Type as int.
class CopierRefCountedTest : public RefCounted<CopierRefCountedTest> {
};

static_assert((std::is_same<int, CrossThreadCopier<RefPtr<CopierRefCountedTest>>::Type>::value), "CrossThreadCopier specialization improperly applied to RefPtr<> of a RefCounted (but not ThreadSafeRefCounted) type");
static_assert((std::is_same<int, CrossThreadCopier<CopierRefCountedTest*>::Type>::value), "CrossThreadCopier specialization improperly applied to raw pointer of a RefCounted (but not ThreadSafeRefCounted) type");

} // namespace WTF