Tools/TestWebKitAPI/Tests/WTF/VectorBorrow.cpp

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#include "config.h"
#include <wtf/Borrow.h>

#include "Helpers/Test.h"
#include <wtf/Vector.h>

namespace TestWebKitAPI {

TEST(WTF_VectorBorrow, ReadWhileBorrowedThenInteriorDestroyAfter)
{
    Vector<uint8_t> vector { 1, 2, 3 };
    {
        auto borrowed = borrow(vector);
        EXPECT_EQ(borrowed->size(), 3u);
        EXPECT_EQ(borrowed.get().span().data(), vector.span().data());
    }
    // The borrow has been released, so interior destruction is allowed again.
    vector.reserveCapacity(vector.capacity() + 1024);
    vector.append(4);
    EXPECT_EQ(vector.size(), 4u);
}

TEST(WTF_VectorBorrow, NestedBorrows)
{
    Vector<uint8_t> vector { 1, 2, 3 };
    {
        auto outer = borrow(vector);
        {
            auto inner = borrow(vector);
            EXPECT_EQ(inner->size(), 3u);
        }
        // The inner borrow restored the outer borrow's state, so the Vector is
        // still borrowed here.
        EXPECT_EQ(outer->size(), 3u);
    }
    vector.append(4);
    EXPECT_EQ(vector.size(), 4u);
}

TEST(WTF_VectorBorrowDeathTest, MAYBE_ASSERT_ENABLED_DEATH_TEST(ReallocateWhileBorrowedCrashes))
{
    auto shouldCrash = [] {
        Vector<uint8_t> vector { 1, 2, 3 };
        auto borrowed = borrow(vector);
        vector.reserveCapacity(vector.capacity() + 1024);
    };
    ASSERT_DEATH_IF_SUPPORTED(shouldCrash(), "");
}

TEST(WTF_VectorBorrowDeathTest, MAYBE_ASSERT_ENABLED_DEATH_TEST(DestroyWhileBorrowedCrashes))
{
    auto shouldCrash = [] {
        auto* vector = new Vector<uint8_t> { 1, 2, 3 };
        auto borrowed = borrow(*vector);
        delete vector; // Destroys the Vector while the borrow is outstanding.
    };
    ASSERT_DEATH_IF_SUPPORTED(shouldCrash(), "");
}

TEST(WTF_VectorBorrowDeathTest, MAYBE_ASSERT_ENABLED_DEATH_TEST(SwapWhileBorrowedCrashes))
{
    auto shouldCrash = [] {
        Vector<uint8_t> vector { 1, 2, 3 };
        Vector<uint8_t> other { 4, 5, 6 };
        auto borrowed = borrow(vector);
        vector.swap(other);
    };
    ASSERT_DEATH_IF_SUPPORTED(shouldCrash(), "");
}

TEST(WTF_VectorBorrowDeathTest, MAYBE_ASSERT_ENABLED_DEATH_TEST(MoveWhileBorrowedCrashes))
{
    auto shouldCrash = [] {
        Vector<uint8_t> vector { 1, 2, 3 };
        auto borrowed = borrow(vector);
        Vector<uint8_t> moved = WTF::move(vector);
    };
    ASSERT_DEATH_IF_SUPPORTED(shouldCrash(), "");
}

} // namespace TestWebKitAPI