src/dawn/tests/unittests/native/CacheRequestTests.cpp - dawn - Git at Google

 // Copyright 2022 The Dawn & Tint Authors
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are met:
 //
 // 1. Redistributions of source code must retain the above copyright notice, this
 //    list of conditions and the following disclaimer.
 //
 // 2. Redistributions in binary form must reproduce the above copyright notice,
 //    this list of conditions and the following disclaimer in the documentation
 //    and/or other materials provided with the distribution.
 //
 // 3. Neither the name of the copyright holder nor the names of its
 //    contributors may be used to endorse or promote products derived from
 //    this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 #include <memory>
 #include <utility>
 #include <vector>

 #include "dawn/native/Blob.h"
 #include "dawn/native/CacheRequest.h"
 #include "dawn/tests/DawnNativeTest.h"
 #include "dawn/tests/mocks/platform/CachingInterfaceMock.h"

 namespace dawn::native {
 namespace {

 using ::testing::_;
 using ::testing::ByMove;
 using ::testing::Invoke;
 using ::testing::MockFunction;
 using ::testing::Return;
 using ::testing::StrictMock;
 using ::testing::WithArg;

 class CacheRequestTests : public DawnNativeTest {
   protected:
     std::unique_ptr<dawn::platform::Platform> CreateTestPlatform() override {
         return std::make_unique<DawnCachingMockPlatform>(&mMockCache);
     }

     DeviceBase* GetDevice() { return dawn::native::FromAPI(device.Get()); }

     StrictMock<CachingInterfaceMock> mMockCache;
 };

 struct Foo {
     int value;
 };

 #define REQUEST_MEMBERS(X)                   \
     X(int, a)                                \
     X(float, b)                              \
     X(std::vector<unsigned int>, c)          \
     X(CacheKey::UnsafeUnkeyedValue<int*>, d) \
     X(CacheKey::UnsafeUnkeyedValue<Foo>, e)

 DAWN_MAKE_CACHE_REQUEST(CacheRequestForTesting, REQUEST_MEMBERS);

 #undef REQUEST_MEMBERS

 // static_assert the expected types for various return types from the cache hit handler and cache
 // miss handler.
 TEST_F(CacheRequestTests, CacheResultTypes) {
     EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillRepeatedly(Return(0));

     // (int, ResultOrError<int>), should be ResultOrError<CacheResult<int>>.
     auto v1 = LoadOrRun(
         GetDevice(), CacheRequestForTesting{}, [](Blob) -> int { return 0; },
         [](CacheRequestForTesting) -> ResultOrError<int> { return 1; });
     v1.AcquireSuccess();
     static_assert(std::is_same_v<ResultOrError<CacheResult<int>>, decltype(v1)>);

     // (ResultOrError<float>, ResultOrError<float>), should be ResultOrError<CacheResult<float>>.
     auto v2 = LoadOrRun(
         GetDevice(), CacheRequestForTesting{}, [](Blob) -> ResultOrError<float> { return 0.0; },
         [](CacheRequestForTesting) -> ResultOrError<float> { return 1.0; });
     v2.AcquireSuccess();
     static_assert(std::is_same_v<ResultOrError<CacheResult<float>>, decltype(v2)>);
 }

 // Test that using a CacheRequest builds a key from the device key, the request type enum, and all
 // of the request members.
 TEST_F(CacheRequestTests, MakesCacheKey) {
     // Make a request.
     CacheRequestForTesting req;
     req.a = 1;
     req.b = 0.2;
     req.c = {3, 4, 5};

     // Make the expected key.
     CacheKey expectedKey;
     StreamIn(&expectedKey, GetDevice()->GetCacheKey(), "CacheRequestForTesting", req.a, req.b,
              req.c);

     // Expect a call to LoadData with the expected key.
     EXPECT_CALL(mMockCache, LoadData(_, expectedKey.size(), nullptr, 0))
         .WillOnce(WithArg<0>(Invoke([&](const void* actualKeyData) {
             EXPECT_EQ(memcmp(actualKeyData, expectedKey.data(), expectedKey.size()), 0);
             return 0;
         })));

     // Load the request.
     auto result = LoadOrRun(
                       GetDevice(), std::move(req), [](Blob) -> int { return 0; },
                       [](CacheRequestForTesting) -> ResultOrError<int> { return 0; })
                       .AcquireSuccess();

     // The created cache key should be saved on the result.
     EXPECT_EQ(result.GetCacheKey().size(), expectedKey.size());
     EXPECT_EQ(memcmp(result.GetCacheKey().data(), expectedKey.data(), expectedKey.size()), 0);
 }

 // Test that members that are wrapped in UnsafeUnkeyedValue do not impact the key.
 TEST_F(CacheRequestTests, CacheKeyIgnoresUnsafeIgnoredValue) {
     // Make two requests with different UnsafeUnkeyedValues (UnsafeUnkeyed is declared on the struct
     // definition).
     int v1, v2;
     CacheRequestForTesting req1;
     req1.d = &v1;
     req1.e = Foo{42};

     CacheRequestForTesting req2;
     req2.d = &v2;
     req2.e = Foo{24};

     EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillOnce(Return(0)).WillOnce(Return(0));

     static StrictMock<MockFunction<int(CacheRequestForTesting)>> cacheMissFn;

     // Load the first request, and check that the unsafe unkeyed values were passed though
     EXPECT_CALL(cacheMissFn, Call(_)).WillOnce(WithArg<0>(Invoke([&](CacheRequestForTesting req) {
         EXPECT_EQ(req.d.UnsafeGetValue(), &v1);
         EXPECT_FLOAT_EQ(req.e.UnsafeGetValue().value, 42);
         return 0;
     })));
     auto r1 = LoadOrRun(
                   GetDevice(), std::move(req1), [](Blob) { return 0; },
                   [](CacheRequestForTesting req) -> ResultOrError<int> {
                       return cacheMissFn.Call(std::move(req));
                   })
                   .AcquireSuccess();

     // Load the second request, and check that the unsafe unkeyed values were passed though
     EXPECT_CALL(cacheMissFn, Call(_)).WillOnce(WithArg<0>(Invoke([&](CacheRequestForTesting req) {
         EXPECT_EQ(req.d.UnsafeGetValue(), &v2);
         EXPECT_FLOAT_EQ(req.e.UnsafeGetValue().value, 24);
         return 0;
     })));
     auto r2 = LoadOrRun(
                   GetDevice(), std::move(req2), [](Blob) { return 0; },
                   [](CacheRequestForTesting req) -> ResultOrError<int> {
                       return cacheMissFn.Call(std::move(req));
                   })
                   .AcquireSuccess();

     // Expect their keys to be the same.
     EXPECT_EQ(r1.GetCacheKey().size(), r2.GetCacheKey().size());
     EXPECT_EQ(memcmp(r1.GetCacheKey().data(), r2.GetCacheKey().data(), r1.GetCacheKey().size()), 0);
 }

 // Test the expected code path when there is a cache miss.
 TEST_F(CacheRequestTests, CacheMiss) {
     // Make a request.
     CacheRequestForTesting req;
     req.a = 1;
     req.b = 0.2;
     req.c = {3, 4, 5};

     unsigned int* cPtr = req.c.data();

     static StrictMock<MockFunction<int(Blob)>> cacheHitFn;
     static StrictMock<MockFunction<int(CacheRequestForTesting)>> cacheMissFn;

     // Mock a cache miss.
     EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillOnce(Return(0));

     // Expect the cache miss, and return some value.
     int rv = 42;
     EXPECT_CALL(cacheMissFn, Call(_)).WillOnce(WithArg<0>(Invoke([=](CacheRequestForTesting req) {
         // Expect the request contents to be the same. The data pointer for |c| is also the same
         // since it was moved.
         EXPECT_EQ(req.a, 1);
         EXPECT_FLOAT_EQ(req.b, 0.2);
         EXPECT_EQ(req.c.data(), cPtr);
         return rv;
     })));

     // Load the request.
     auto result = LoadOrRun(
                       GetDevice(), std::move(req),
                       [](Blob blob) -> int { return cacheHitFn.Call(std::move(blob)); },
                       [](CacheRequestForTesting req) -> ResultOrError<int> {
                           return cacheMissFn.Call(std::move(req));
                       })
                       .AcquireSuccess();

     // Expect the result to store the value.
     EXPECT_EQ(*result, rv);
     EXPECT_FALSE(result.IsCached());
 }

 // Test the expected code path when there is a cache hit.
 TEST_F(CacheRequestTests, CacheHit) {
     // Make a request.
     CacheRequestForTesting req;
     req.a = 1;
     req.b = 0.2;
     req.c = {3, 4, 5};

     static StrictMock<MockFunction<int(Blob)>> cacheHitFn;
     static StrictMock<MockFunction<int(CacheRequestForTesting)>> cacheMissFn;

     static constexpr char kCachedData[] = "hello world!";

     // Mock a cache hit, and load the cached data.
     EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillOnce(Return(sizeof(kCachedData)));
     EXPECT_CALL(mMockCache, LoadData(_, _, _, sizeof(kCachedData)))
         .WillOnce(WithArg<2>(Invoke([](void* dataOut) {
             memcpy(dataOut, kCachedData, sizeof(kCachedData));
             return sizeof(kCachedData);
         })));

     // Expect the cache hit, and return some value.
     int rv = 1337;
     EXPECT_CALL(cacheHitFn, Call(_)).WillOnce(WithArg<0>(Invoke([=](Blob blob) {
         // Expect the cached blob contents to match the cached data.
         EXPECT_EQ(blob.Size(), sizeof(kCachedData));
         EXPECT_EQ(memcmp(blob.Data(), kCachedData, sizeof(kCachedData)), 0);

         return rv;
     })));

     // Load the request.
     auto result = LoadOrRun(
                       GetDevice(), std::move(req),
                       [](Blob blob) -> int { return cacheHitFn.Call(std::move(blob)); },
                       [](CacheRequestForTesting req) -> ResultOrError<int> {
                           return cacheMissFn.Call(std::move(req));
                       })
                       .AcquireSuccess();

     // Expect the result to store the value.
     EXPECT_EQ(*result, rv);
     EXPECT_TRUE(result.IsCached());
 }

 // Test the expected code path when there is a cache hit but the handler errors.
 TEST_F(CacheRequestTests, CacheHitError) {
     // Make a request.
     CacheRequestForTesting req;
     req.a = 1;
     req.b = 0.2;
     req.c = {3, 4, 5};

     unsigned int* cPtr = req.c.data();

     static StrictMock<MockFunction<ResultOrError<int>(Blob)>> cacheHitFn;
     static StrictMock<MockFunction<int(CacheRequestForTesting)>> cacheMissFn;

     static constexpr char kCachedData[] = "hello world!";

     // Mock a cache hit, and load the cached data.
     EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillOnce(Return(sizeof(kCachedData)));
     EXPECT_CALL(mMockCache, LoadData(_, _, _, sizeof(kCachedData)))
         .WillOnce(WithArg<2>(Invoke([](void* dataOut) {
             memcpy(dataOut, kCachedData, sizeof(kCachedData));
             return sizeof(kCachedData);
         })));

     // Expect the cache hit.
     EXPECT_CALL(cacheHitFn, Call(_)).WillOnce(WithArg<0>(Invoke([=](Blob blob) {
         // Expect the cached blob contents to match the cached data.
         EXPECT_EQ(blob.Size(), sizeof(kCachedData));
         EXPECT_EQ(memcmp(blob.Data(), kCachedData, sizeof(kCachedData)), 0);

         // Return an error.
         return DAWN_VALIDATION_ERROR("fake test error");
     })));

     // Expect the cache miss handler since the cache hit errored.
     int rv = 79;
     EXPECT_CALL(cacheMissFn, Call(_)).WillOnce(WithArg<0>(Invoke([=](CacheRequestForTesting req) {
         // Expect the request contents to be the same. The data pointer for |c| is also the same
         // since it was moved.
         EXPECT_EQ(req.a, 1);
         EXPECT_FLOAT_EQ(req.b, 0.2);
         EXPECT_EQ(req.c.data(), cPtr);
         return rv;
     })));

     // Load the request.
     auto result =
         LoadOrRun(
             GetDevice(), std::move(req),
             [](Blob blob) -> ResultOrError<int> { return cacheHitFn.Call(std::move(blob)); },
             [](CacheRequestForTesting req) -> ResultOrError<int> {
                 return cacheMissFn.Call(std::move(req));
             })
             .AcquireSuccess();

     // Expect the result to store the value.
     EXPECT_EQ(*result, rv);
     EXPECT_FALSE(result.IsCached());
 }

 }  // anonymous namespace
 }  // namespace dawn::native
	// Copyright 2022 The Dawn & Tint Authors
	//
	// Redistribution and use in source and binary forms, with or without
	// modification, are permitted provided that the following conditions are met:
	//
	// 1. Redistributions of source code must retain the above copyright notice, this
	// list of conditions and the following disclaimer.
	//
	// 2. Redistributions in binary form must reproduce the above copyright notice,
	// this list of conditions and the following disclaimer in the documentation
	// and/or other materials provided with the distribution.
	//
	// 3. Neither the name of the copyright holder nor the names of its
	// contributors may be used to endorse or promote products derived from
	// this software without specific prior written permission.
	//
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
	// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	#include <memory>
	#include <utility>
	#include <vector>

	#include "dawn/native/Blob.h"
	#include "dawn/native/CacheRequest.h"
	#include "dawn/tests/DawnNativeTest.h"
	#include "dawn/tests/mocks/platform/CachingInterfaceMock.h"

	namespace dawn::native {
	namespace {

	using ::testing::_;
	using ::testing::ByMove;
	using ::testing::Invoke;
	using ::testing::MockFunction;
	using ::testing::Return;
	using ::testing::StrictMock;
	using ::testing::WithArg;

	class CacheRequestTests : public DawnNativeTest {
	protected:
	std::unique_ptr<dawn::platform::Platform> CreateTestPlatform() override {
	return std::make_unique<DawnCachingMockPlatform>(&mMockCache);
	}

	DeviceBase* GetDevice() { return dawn::native::FromAPI(device.Get()); }

	StrictMock<CachingInterfaceMock> mMockCache;
	};

	struct Foo {
	int value;
	};

	#define REQUEST_MEMBERS(X) \
	X(int, a) \
	X(float, b) \
	X(std::vector<unsigned int>, c) \
	X(CacheKey::UnsafeUnkeyedValue<int*>, d) \
	X(CacheKey::UnsafeUnkeyedValue<Foo>, e)

	DAWN_MAKE_CACHE_REQUEST(CacheRequestForTesting, REQUEST_MEMBERS);

	#undef REQUEST_MEMBERS

	// static_assert the expected types for various return types from the cache hit handler and cache
	// miss handler.
	TEST_F(CacheRequestTests, CacheResultTypes) {
	EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillRepeatedly(Return(0));

	// (int, ResultOrError<int>), should be ResultOrError<CacheResult<int>>.
	auto v1 = LoadOrRun(
	GetDevice(), CacheRequestForTesting{}, [](Blob) -> int { return 0; },
	[](CacheRequestForTesting) -> ResultOrError<int> { return 1; });
	v1.AcquireSuccess();
	static_assert(std::is_same_v<ResultOrError<CacheResult<int>>, decltype(v1)>);

	// (ResultOrError<float>, ResultOrError<float>), should be ResultOrError<CacheResult<float>>.
	auto v2 = LoadOrRun(
	GetDevice(), CacheRequestForTesting{}, [](Blob) -> ResultOrError<float> { return 0.0; },
	[](CacheRequestForTesting) -> ResultOrError<float> { return 1.0; });
	v2.AcquireSuccess();
	static_assert(std::is_same_v<ResultOrError<CacheResult<float>>, decltype(v2)>);
	}

	// Test that using a CacheRequest builds a key from the device key, the request type enum, and all
	// of the request members.
	TEST_F(CacheRequestTests, MakesCacheKey) {
	// Make a request.
	CacheRequestForTesting req;
	req.a = 1;
	req.b = 0.2;
	req.c = {3, 4, 5};

	// Make the expected key.
	CacheKey expectedKey;
	StreamIn(&expectedKey, GetDevice()->GetCacheKey(), "CacheRequestForTesting", req.a, req.b,
	req.c);

	// Expect a call to LoadData with the expected key.
	EXPECT_CALL(mMockCache, LoadData(_, expectedKey.size(), nullptr, 0))
	.WillOnce(WithArg<0>(Invoke([&](const void* actualKeyData) {
	EXPECT_EQ(memcmp(actualKeyData, expectedKey.data(), expectedKey.size()), 0);
	return 0;
	})));

	// Load the request.
	auto result = LoadOrRun(
	GetDevice(), std::move(req), [](Blob) -> int { return 0; },
	[](CacheRequestForTesting) -> ResultOrError<int> { return 0; })
	.AcquireSuccess();

	// The created cache key should be saved on the result.
	EXPECT_EQ(result.GetCacheKey().size(), expectedKey.size());
	EXPECT_EQ(memcmp(result.GetCacheKey().data(), expectedKey.data(), expectedKey.size()), 0);
	}

	// Test that members that are wrapped in UnsafeUnkeyedValue do not impact the key.
	TEST_F(CacheRequestTests, CacheKeyIgnoresUnsafeIgnoredValue) {
	// Make two requests with different UnsafeUnkeyedValues (UnsafeUnkeyed is declared on the struct
	// definition).
	int v1, v2;
	CacheRequestForTesting req1;
	req1.d = &v1;
	req1.e = Foo{42};

	CacheRequestForTesting req2;
	req2.d = &v2;
	req2.e = Foo{24};

	EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillOnce(Return(0)).WillOnce(Return(0));

	static StrictMock<MockFunction<int(CacheRequestForTesting)>> cacheMissFn;

	// Load the first request, and check that the unsafe unkeyed values were passed though
	EXPECT_CALL(cacheMissFn, Call(_)).WillOnce(WithArg<0>(Invoke([&](CacheRequestForTesting req) {
	EXPECT_EQ(req.d.UnsafeGetValue(), &v1);
	EXPECT_FLOAT_EQ(req.e.UnsafeGetValue().value, 42);
	return 0;
	})));
	auto r1 = LoadOrRun(
	GetDevice(), std::move(req1), [](Blob) { return 0; },
	[](CacheRequestForTesting req) -> ResultOrError<int> {
	return cacheMissFn.Call(std::move(req));
	})
	.AcquireSuccess();

	// Load the second request, and check that the unsafe unkeyed values were passed though
	EXPECT_CALL(cacheMissFn, Call(_)).WillOnce(WithArg<0>(Invoke([&](CacheRequestForTesting req) {
	EXPECT_EQ(req.d.UnsafeGetValue(), &v2);
	EXPECT_FLOAT_EQ(req.e.UnsafeGetValue().value, 24);
	return 0;
	})));
	auto r2 = LoadOrRun(
	GetDevice(), std::move(req2), [](Blob) { return 0; },
	[](CacheRequestForTesting req) -> ResultOrError<int> {
	return cacheMissFn.Call(std::move(req));
	})
	.AcquireSuccess();

	// Expect their keys to be the same.
	EXPECT_EQ(r1.GetCacheKey().size(), r2.GetCacheKey().size());
	EXPECT_EQ(memcmp(r1.GetCacheKey().data(), r2.GetCacheKey().data(), r1.GetCacheKey().size()), 0);
	}

	// Test the expected code path when there is a cache miss.
	TEST_F(CacheRequestTests, CacheMiss) {
	// Make a request.
	CacheRequestForTesting req;
	req.a = 1;
	req.b = 0.2;
	req.c = {3, 4, 5};

	unsigned int* cPtr = req.c.data();

	static StrictMock<MockFunction<int(Blob)>> cacheHitFn;
	static StrictMock<MockFunction<int(CacheRequestForTesting)>> cacheMissFn;

	// Mock a cache miss.
	EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillOnce(Return(0));

	// Expect the cache miss, and return some value.
	int rv = 42;
	EXPECT_CALL(cacheMissFn, Call(_)).WillOnce(WithArg<0>(Invoke([=](CacheRequestForTesting req) {
	// Expect the request contents to be the same. The data pointer for \|c\| is also the same
	// since it was moved.
	EXPECT_EQ(req.a, 1);
	EXPECT_FLOAT_EQ(req.b, 0.2);
	EXPECT_EQ(req.c.data(), cPtr);
	return rv;
	})));

	// Load the request.
	auto result = LoadOrRun(
	GetDevice(), std::move(req),
	[](Blob blob) -> int { return cacheHitFn.Call(std::move(blob)); },
	[](CacheRequestForTesting req) -> ResultOrError<int> {
	return cacheMissFn.Call(std::move(req));
	})
	.AcquireSuccess();

	// Expect the result to store the value.
	EXPECT_EQ(*result, rv);
	EXPECT_FALSE(result.IsCached());
	}

	// Test the expected code path when there is a cache hit.
	TEST_F(CacheRequestTests, CacheHit) {
	// Make a request.
	CacheRequestForTesting req;
	req.a = 1;
	req.b = 0.2;
	req.c = {3, 4, 5};

	static StrictMock<MockFunction<int(Blob)>> cacheHitFn;
	static StrictMock<MockFunction<int(CacheRequestForTesting)>> cacheMissFn;

	static constexpr char kCachedData[] = "hello world!";

	// Mock a cache hit, and load the cached data.
	EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillOnce(Return(sizeof(kCachedData)));
	EXPECT_CALL(mMockCache, LoadData(_, _, _, sizeof(kCachedData)))
	.WillOnce(WithArg<2>(Invoke([](void* dataOut) {
	memcpy(dataOut, kCachedData, sizeof(kCachedData));
	return sizeof(kCachedData);
	})));

	// Expect the cache hit, and return some value.
	int rv = 1337;
	EXPECT_CALL(cacheHitFn, Call(_)).WillOnce(WithArg<0>(Invoke([=](Blob blob) {
	// Expect the cached blob contents to match the cached data.
	EXPECT_EQ(blob.Size(), sizeof(kCachedData));
	EXPECT_EQ(memcmp(blob.Data(), kCachedData, sizeof(kCachedData)), 0);

	return rv;
	})));

	// Load the request.
	auto result = LoadOrRun(
	GetDevice(), std::move(req),
	[](Blob blob) -> int { return cacheHitFn.Call(std::move(blob)); },
	[](CacheRequestForTesting req) -> ResultOrError<int> {
	return cacheMissFn.Call(std::move(req));
	})
	.AcquireSuccess();

	// Expect the result to store the value.
	EXPECT_EQ(*result, rv);
	EXPECT_TRUE(result.IsCached());
	}

	// Test the expected code path when there is a cache hit but the handler errors.
	TEST_F(CacheRequestTests, CacheHitError) {
	// Make a request.
	CacheRequestForTesting req;
	req.a = 1;
	req.b = 0.2;
	req.c = {3, 4, 5};

	unsigned int* cPtr = req.c.data();

	static StrictMock<MockFunction<ResultOrError<int>(Blob)>> cacheHitFn;
	static StrictMock<MockFunction<int(CacheRequestForTesting)>> cacheMissFn;

	static constexpr char kCachedData[] = "hello world!";

	// Mock a cache hit, and load the cached data.
	EXPECT_CALL(mMockCache, LoadData(_, _, nullptr, 0)).WillOnce(Return(sizeof(kCachedData)));
	EXPECT_CALL(mMockCache, LoadData(_, _, _, sizeof(kCachedData)))
	.WillOnce(WithArg<2>(Invoke([](void* dataOut) {
	memcpy(dataOut, kCachedData, sizeof(kCachedData));
	return sizeof(kCachedData);
	})));

	// Expect the cache hit.
	EXPECT_CALL(cacheHitFn, Call(_)).WillOnce(WithArg<0>(Invoke([=](Blob blob) {
	// Expect the cached blob contents to match the cached data.
	EXPECT_EQ(blob.Size(), sizeof(kCachedData));
	EXPECT_EQ(memcmp(blob.Data(), kCachedData, sizeof(kCachedData)), 0);

	// Return an error.
	return DAWN_VALIDATION_ERROR("fake test error");
	})));

	// Expect the cache miss handler since the cache hit errored.
	int rv = 79;
	EXPECT_CALL(cacheMissFn, Call(_)).WillOnce(WithArg<0>(Invoke([=](CacheRequestForTesting req) {
	// Expect the request contents to be the same. The data pointer for \|c\| is also the same
	// since it was moved.
	EXPECT_EQ(req.a, 1);
	EXPECT_FLOAT_EQ(req.b, 0.2);
	EXPECT_EQ(req.c.data(), cPtr);
	return rv;
	})));

	// Load the request.
	auto result =
	LoadOrRun(
	GetDevice(), std::move(req),
	[](Blob blob) -> ResultOrError<int> { return cacheHitFn.Call(std::move(blob)); },
	[](CacheRequestForTesting req) -> ResultOrError<int> {
	return cacheMissFn.Call(std::move(req));
	})
	.AcquireSuccess();

	// Expect the result to store the value.
	EXPECT_EQ(*result, rv);
	EXPECT_FALSE(result.IsCached());
	}

	} // anonymous namespace
	} // namespace dawn::native