Implement BlobBytesConsumer

third_party/WebKit/Source/modules/fetch/BlobBytesConsumerTest.cpp

+// 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/fetch/BlobBytesConsumer.h"
+
+#include "core/dom/Document.h"
+#include "core/loader/ThreadableLoader.h"
+#include "core/testing/DummyPageHolder.h"
+#include "modules/fetch/BytesConsumerTestUtil.h"
+#include "modules/fetch/DataConsumerHandleTestUtil.h"
+#include "platform/blob/BlobData.h"
+#include "platform/network/EncodedFormData.h"
+#include "platform/network/ResourceError.h"
+#include "platform/network/ResourceResponse.h"
+#include "platform/testing/UnitTestHelpers.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "wtf/Vector.h"
+#include "wtf/text/WTFString.h"
+
+namespace blink {
+
+namespace {
+
+using Command = DataConsumerHandleTestUtil::Command;
+using PublicState = BytesConsumer::PublicState;
+using ReplayingHandle = DataConsumerHandleTestUtil::ReplayingHandle;
+using Result = BytesConsumer::Result;
+
+String toString(const Vector<char>& v)
+{
+    return String(v.data(), v.size());
+}
+
+class TestThreadableLoader : public ThreadableLoader {
+public:
+    ~TestThreadableLoader() override
+    {
+        EXPECT_FALSE(m_shouldBeCancelled && !m_isCancelled) << "The loader should be cancelled but is not cancelled.";
+    }
+
+    void start(const ResourceRequest& request) override
+    {
+        m_isStarted = true;
+    }
+
+    void overrideTimeout(unsigned long timeoutMilliseconds) override
+    {
+        ADD_FAILURE() << "overrideTimeout should not be called.";
+    }
+
+    void cancel() override
+    {
+        m_isCancelled = true;
+    }
+
+    bool isStarted() const { return m_isStarted; }
+    bool isCancelled() const { return m_isCancelled; }
+    void setShouldBeCancelled() { m_shouldBeCancelled = true; }
+
+private:
+    bool m_isStarted = false;
+    bool m_isCancelled = false;
+    bool m_shouldBeCancelled = false;
+};
+
+class SyncLoadingTestThreadableLoader : public ThreadableLoader {
+public:
+    ~SyncLoadingTestThreadableLoader() override
+    {
+        DCHECK(!m_handle);
+    }
+
+    void start(const ResourceRequest& request) override
+    {
+        m_isStarted = true;
+        m_client->didReceiveResponse(0, ResourceResponse(), std::move(m_handle));
+        m_client->didFinishLoading(0, 0);
+    }
+
+    void overrideTimeout(unsigned long timeoutMilliseconds) override
+    {
+        ADD_FAILURE() << "overrideTimeout should not be called.";
+    }
+
+    void cancel() override
+    {
+        m_isCancelled = true;
+    }
+
+    bool isStarted() const { return m_isStarted; }
+    bool isCancelled() const { return m_isCancelled; }
+
+    void setClient(ThreadableLoaderClient* client)
+    {
+        m_client = client;
+    }
+
+    void setHandle(std::unique_ptr<WebDataConsumerHandle> handle)
+    {
+        m_handle = std::move(handle);
+    }
+
+private:
+    bool m_isStarted = false;
+    bool m_isCancelled = false;
+    ThreadableLoaderClient* m_client = nullptr;
+    std::unique_ptr<WebDataConsumerHandle> m_handle;
+};
+
+class SyncErrorTestThreadableLoader : public ThreadableLoader {
+public:
+    ~SyncErrorTestThreadableLoader() override {}
+
+    void start(const ResourceRequest& request) override
+    {
+        m_isStarted = true;
+        m_client->didFail(ResourceError());
+    }
+
+    void overrideTimeout(unsigned long timeoutMilliseconds) override
+    {
+        ADD_FAILURE() << "overrideTimeout should not be called.";
+    }
+
+    void cancel() override
+    {
+        m_isCancelled = true;
+    }
+
+    bool isStarted() const { return m_isStarted; }
+    bool isCancelled() const { return m_isCancelled; }
+
+    void setClient(ThreadableLoaderClient* client)
+    {
+        m_client = client;
+    }
+
+private:
+    bool m_isStarted = false;
+    bool m_isCancelled = false;
+    ThreadableLoaderClient* m_client = nullptr;
+};
+
+class TestClient final : public GarbageCollectedFinalized<TestClient>, public BytesConsumer::Client {
+    USING_GARBAGE_COLLECTED_MIXIN(TestClient);
+public:
+    void onStateChange() override { ++m_numOnStateChangeCalled; }
+    int numOnStateChangeCalled() const { return m_numOnStateChangeCalled; }
+
+private:
+    int m_numOnStateChangeCalled = 0;
+};
+
+class BlobBytesConsumerTest : public ::testing::Test {
+public:
+    BlobBytesConsumerTest()
+        : m_dummyPageHolder(DummyPageHolder::create(IntSize(1, 1))) {}
+
+    Document& document() { return m_dummyPageHolder->document(); }
+
+private:
+    std::unique_ptr<DummyPageHolder> m_dummyPageHolder;
+};
+
+TEST_F(BlobBytesConsumerTest, Read)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    std::unique_ptr<ReplayingHandle> src = ReplayingHandle::create();
+    src->add(Command(Command::Data, "hello, "));
+    src->add(Command(Command::Wait));
+    src->add(Command(Command::Data, "world"));
+    src->add(Command(Command::Done));
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_FALSE(loader->isStarted());
+
+    char buffer[3];
+    size_t read = 0;
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+    EXPECT_FALSE(consumer->drainAsBlobDataHandle(BytesConsumer::BlobSizePolicy::AllowBlobWithInvalidSize));
+    EXPECT_FALSE(consumer->drainAsFormData());
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+
+    consumer->didReceiveResponse(0, ResourceResponse(), std::move(src));
+    consumer->didFinishLoading(0, 0);
+
+    auto result = (new BytesConsumerTestUtil::Reader(consumer))->run();
+    EXPECT_EQ(Result::Done, result.first);
+    EXPECT_EQ("hello, world", toString(result.second));
+}
+
+TEST_F(BlobBytesConsumerTest, TwoPhaseRead)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    std::unique_ptr<ReplayingHandle> src = ReplayingHandle::create();
+    src->add(Command(Command::Data, "hello, "));
+    src->add(Command(Command::Wait));
+    src->add(Command(Command::Data, "world"));
+    src->add(Command(Command::Done));
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_FALSE(loader->isStarted());
+
+    char buffer[3];
+    size_t read = 0;
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+    EXPECT_FALSE(consumer->drainAsBlobDataHandle(BytesConsumer::BlobSizePolicy::AllowBlobWithInvalidSize));
+    EXPECT_FALSE(consumer->drainAsFormData());
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+
+    consumer->didReceiveResponse(0, ResourceResponse(), std::move(src));
+    consumer->didFinishLoading(0, 0);
+
+    auto result = (new BytesConsumerTestUtil::TwoPhaseReader(consumer))->run();
+    EXPECT_EQ(Result::Done, result.first);
+    EXPECT_EQ("hello, world", toString(result.second));
+}
+
+TEST_F(BlobBytesConsumerTest, FailLoading)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    TestClient* client = new TestClient();
+    consumer->setClient(client);
+
+    char buffer[3];
+    size_t read = 0;
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+
+    int numOnStateChangeCalled = client->numOnStateChangeCalled();
+    consumer->didFail(ResourceError());
+
+    EXPECT_EQ(numOnStateChangeCalled + 1, client->numOnStateChangeCalled());
+    EXPECT_EQ(PublicState::Errored, consumer->getPublicState());
+    EXPECT_EQ(Result::Error, consumer->read(buffer, sizeof(buffer), &read));
+}
+
+TEST_F(BlobBytesConsumerTest, FailLoadingAfterResponseReceived)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    TestClient* client = new TestClient();
+    consumer->setClient(client);
+
+    char buffer[3];
+    size_t read = 0;
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+
+    int numOnStateChangeCalled = client->numOnStateChangeCalled();
+    consumer->didReceiveResponse(0, ResourceResponse(), createWaitingDataConsumerHandle());
+    EXPECT_EQ(numOnStateChangeCalled + 1, client->numOnStateChangeCalled());
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+
+    consumer->didFail(ResourceError());
+    EXPECT_EQ(numOnStateChangeCalled + 2, client->numOnStateChangeCalled());
+    EXPECT_EQ(PublicState::Errored, consumer->getPublicState());
+    EXPECT_EQ(Result::Error, consumer->read(buffer, sizeof(buffer), &read));
+}
+
+TEST_F(BlobBytesConsumerTest, FailAccessControlCheck)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    TestClient* client = new TestClient();
+    consumer->setClient(client);
+
+    char buffer[3];
+    size_t read = 0;
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+
+    int numOnStateChangeCalled = client->numOnStateChangeCalled();
+    consumer->didFailAccessControlCheck(ResourceError());
+    EXPECT_EQ(numOnStateChangeCalled + 1, client->numOnStateChangeCalled());
+
+    EXPECT_EQ(PublicState::Errored, consumer->getPublicState());
+    EXPECT_EQ(Result::Error, consumer->read(buffer, sizeof(buffer), &read));
+}
+
+TEST_F(BlobBytesConsumerTest, CancelBeforeStarting)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    TestClient* client = new TestClient();
+    consumer->setClient(client);
+
+    consumer->cancel();
+    // This should be FALSE in production, but TRUE here because we set the
+    // loader before starting loading in tests.
+    EXPECT_TRUE(loader->isCancelled());
+
+    char buffer[3];
+    size_t read = 0;
+    EXPECT_EQ(PublicState::Closed, consumer->getPublicState());
+    EXPECT_EQ(Result::Done, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_FALSE(loader->isStarted());
+    EXPECT_EQ(0, client->numOnStateChangeCalled());
+}
+
+TEST_F(BlobBytesConsumerTest, CancelAfterStarting)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    TestClient* client = new TestClient();
+    consumer->setClient(client);
+
+    char buffer[3];
+    size_t read = 0;
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+    EXPECT_EQ(0, client->numOnStateChangeCalled());
+
+    consumer->cancel();
+    EXPECT_TRUE(loader->isCancelled());
+    EXPECT_EQ(PublicState::Closed, consumer->getPublicState());
+    EXPECT_EQ(Result::Done, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_EQ(0, client->numOnStateChangeCalled());
+}
+
+TEST_F(BlobBytesConsumerTest, ReadLastChunkBeforeDidFinishLoadingArrives)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    TestClient* client = new TestClient();
+    consumer->setClient(client);
+    std::unique_ptr<ReplayingHandle> src = ReplayingHandle::create();
+    src->add(Command(Command::Data, "hello"));
+    src->add(Command(Command::Done));
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_FALSE(loader->isStarted());
+
+    char buffer[128];
+    size_t read = 0;
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+    EXPECT_EQ(0, client->numOnStateChangeCalled());
+
+    consumer->didReceiveResponse(0, ResourceResponse(), std::move(src));
+    EXPECT_EQ(1, client->numOnStateChangeCalled());
+    testing::runPendingTasks();
+    EXPECT_EQ(2, client->numOnStateChangeCalled());
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_EQ(Result::Ok, consumer->read(buffer, sizeof(buffer), &read));
+    ASSERT_EQ(5u, read);
+    EXPECT_EQ("hello", String(buffer, read));
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+
+    consumer->didFinishLoading(0, 0);
+    EXPECT_EQ(3, client->numOnStateChangeCalled());
+    EXPECT_EQ(PublicState::Closed, consumer->getPublicState());
+    EXPECT_EQ(Result::Done, consumer->read(buffer, sizeof(buffer), &read));
+}
+
+TEST_F(BlobBytesConsumerTest, ReadLastChunkAfterDidFinishLoadingArrives)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    TestClient* client = new TestClient();
+    consumer->setClient(client);
+    std::unique_ptr<ReplayingHandle> src = ReplayingHandle::create();
+    src->add(Command(Command::Data, "hello"));
+    src->add(Command(Command::Done));
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_FALSE(loader->isStarted());
+
+    char buffer[128];
+    size_t read = 0;
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+    EXPECT_EQ(0, client->numOnStateChangeCalled());
+
+    consumer->didReceiveResponse(0, ResourceResponse(), std::move(src));
+    EXPECT_EQ(1, client->numOnStateChangeCalled());
+    testing::runPendingTasks();
+    EXPECT_EQ(2, client->numOnStateChangeCalled());
+
+    consumer->didFinishLoading(0, 0);
+    testing::runPendingTasks();
+    EXPECT_EQ(2, client->numOnStateChangeCalled());
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_EQ(Result::Ok, consumer->read(buffer, sizeof(buffer), &read));
+    ASSERT_EQ(5u, read);
+    EXPECT_EQ("hello", String(buffer, read));
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_EQ(Result::Done, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_EQ(2, client->numOnStateChangeCalled());
+}
+
+TEST_F(BlobBytesConsumerTest, DrainAsBlobDataHandle)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_FALSE(loader->isStarted());
+
+    RefPtr<BlobDataHandle> result = consumer->drainAsBlobDataHandle(BytesConsumer::BlobSizePolicy::DisallowBlobWithInvalidSize);
+    ASSERT_TRUE(result);
+    EXPECT_FALSE(consumer->drainAsBlobDataHandle(BytesConsumer::BlobSizePolicy::DisallowBlobWithInvalidSize));
+    EXPECT_EQ(12345u, result->size());
+}
+
+
+TEST_F(BlobBytesConsumerTest, DrainAsBlobDataHandle_2)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), -1);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_FALSE(loader->isStarted());
+
+    RefPtr<BlobDataHandle> result = consumer->drainAsBlobDataHandle(BytesConsumer::BlobSizePolicy::AllowBlobWithInvalidSize);
+    ASSERT_TRUE(result);
+    EXPECT_FALSE(consumer->drainAsBlobDataHandle(BytesConsumer::BlobSizePolicy::AllowBlobWithInvalidSize));
+    EXPECT_EQ(UINT64_MAX, result->size());
+}
+
+TEST_F(BlobBytesConsumerTest, DrainAsBlobDataHandle_3)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), -1);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_FALSE(loader->isStarted());
+
+    EXPECT_FALSE(consumer->drainAsBlobDataHandle(BytesConsumer::BlobSizePolicy::DisallowBlobWithInvalidSize));
+}
+
+TEST_F(BlobBytesConsumerTest, DrainAsFormData)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    TestThreadableLoader* loader = new TestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+
+    EXPECT_EQ(PublicState::ReadableOrWaiting, consumer->getPublicState());
+    EXPECT_FALSE(loader->isStarted());
+
+    RefPtr<EncodedFormData> result = consumer->drainAsFormData();
+    ASSERT_TRUE(result);
+    ASSERT_EQ(1u, result->elements().size());
+    ASSERT_EQ(FormDataElement::encodedBlob, result->elements()[0].m_type);
+    ASSERT_TRUE(result->elements()[0].m_optionalBlobDataHandle);
+    EXPECT_EQ(12345u, result->elements()[0].m_optionalBlobDataHandle->size());
+    EXPECT_EQ(blobDataHandle->uuid(), result->elements()[0].m_blobUUID);
+}
+
+TEST_F(BlobBytesConsumerTest, LoaderShouldBeCancelled)
+{
+    {
+        RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+        TestThreadableLoader* loader = new TestThreadableLoader();
+        BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+
+        char buffer[3];
+        size_t read = 0;
+        EXPECT_EQ(Result::ShouldWait, consumer->read(buffer, sizeof(buffer), &read));
+        EXPECT_TRUE(loader->isStarted());
+        loader->setShouldBeCancelled();
+    }
+    ThreadState::current()->collectAllGarbage();
+}
+
+TEST_F(BlobBytesConsumerTest, SyncLoading)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    SyncErrorTestThreadableLoader* loader = new SyncErrorTestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    loader->setClient(consumer);
+    TestClient* client = new TestClient();
+    consumer->setClient(client);
+
+    char buffer[3];
+    size_t read = 0;
+    EXPECT_EQ(Result::Error, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+
+    EXPECT_EQ(0, client->numOnStateChangeCalled());
+    EXPECT_EQ(BytesConsumer::PublicState::Errored, consumer->getPublicState());
+}
+
+TEST_F(BlobBytesConsumerTest, SyncErrorDispatch)
+{
+    RefPtr<BlobDataHandle> blobDataHandle = BlobDataHandle::create(BlobData::create(), 12345);
+    SyncLoadingTestThreadableLoader* loader = new SyncLoadingTestThreadableLoader();
+    BlobBytesConsumer* consumer = BlobBytesConsumer::createForTesting(&document(), blobDataHandle, loader);
+    std::unique_ptr<ReplayingHandle> src = ReplayingHandle::create();
+    src->add(Command(Command::Data, "hello, "));
+    src->add(Command(Command::Wait));
+    src->add(Command(Command::Data, "world"));
+    src->add(Command(Command::Done));
+    loader->setClient(consumer);
+    loader->setHandle(std::move(src));
+    TestClient* client = new TestClient();
+    consumer->setClient(client);
+
+    char buffer[3];
+    size_t read = 0;
+    EXPECT_EQ(Result::Ok, consumer->read(buffer, sizeof(buffer), &read));
+    EXPECT_TRUE(loader->isStarted());
+    ASSERT_EQ(3u, read);
+    EXPECT_EQ("hel", String(buffer, read));
+
+    EXPECT_EQ(0, client->numOnStateChangeCalled());
+    EXPECT_EQ(BytesConsumer::PublicState::ReadableOrWaiting, consumer->getPublicState());
+}
+
+} // namespace
+
+} // namespace blink