services/surfaceflinger/tests/unittests/TransactionApplicationTest.cpp

/*
 * Copyright 2019 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#undef LOG_TAG
#define LOG_TAG "CompositionTest"

#include <compositionengine/Display.h>
#include <compositionengine/mock/DisplaySurface.h>
#include <gmock/gmock.h>
#include <gtest/gtest.h>
#include <gui/LayerState.h>
#include <gui/SurfaceComposerClient.h>
#include <gui/fake/BufferData.h>
#include <log/log.h>
#include <ui/MockFence.h>
#include <utils/String8.h>
#include <vector>
#include <binder/Binder.h>

#include "FrontEnd/TransactionHandler.h"
#include "TestableSurfaceFlinger.h"
#include "TransactionState.h"

namespace android {

using testing::_;
using testing::Return;

using frontend::TransactionHandler;

constexpr nsecs_t TRANSACTION_TIMEOUT = s2ns(5);
class TransactionApplicationTest : public testing::Test {
public:
    TransactionApplicationTest() {
        const ::testing::TestInfo* const test_info =
                ::testing::UnitTest::GetInstance()->current_test_info();
        ALOGD("**** Setting up for %s.%s\n", test_info->test_case_name(), test_info->name());

        mFlinger.setupComposer(std::make_unique<Hwc2::mock::Composer>());
        mFlinger.setupMockScheduler();
        mFlinger.flinger()->addTransactionReadyFilters();
    }

    ~TransactionApplicationTest() {
        const ::testing::TestInfo* const test_info =
                ::testing::UnitTest::GetInstance()->current_test_info();
        ALOGD("**** Tearing down after %s.%s\n", test_info->test_case_name(), test_info->name());
    }

    TestableSurfaceFlinger mFlinger;

    struct TransactionInfo {
        Vector<ComposerState> states;
        Vector<DisplayState> displays;
        uint32_t flags = 0;
        sp<IBinder> applyToken = IInterface::asBinder(TransactionCompletedListener::getIInstance());
        InputWindowCommands inputWindowCommands;
        int64_t desiredPresentTime = 0;
        bool isAutoTimestamp = true;
        FrameTimelineInfo frameTimelineInfo;
        std::vector<client_cache_t> uncacheBuffers;
        uint64_t id = static_cast<uint64_t>(-1);
        std::vector<uint64_t> mergedTransactionIds;
        static_assert(0xffffffffffffffff == static_cast<uint64_t>(-1));
    };

    void checkEqual(TransactionInfo info, TransactionState state) {
        EXPECT_EQ(0u, info.states.size());
        EXPECT_EQ(0u, state.states.size());

        EXPECT_EQ(0u, info.displays.size());
        EXPECT_EQ(0u, state.displays.size());
        EXPECT_EQ(info.flags, state.flags);
        EXPECT_EQ(info.desiredPresentTime, state.desiredPresentTime);
    }

    void setupSingle(TransactionInfo& transaction, uint32_t flags, int64_t desiredPresentTime,
                     bool isAutoTimestamp, const FrameTimelineInfo& frameTimelineInfo) {
        mTransactionNumber++;
        transaction.flags |= flags;
        transaction.desiredPresentTime = desiredPresentTime;
        transaction.isAutoTimestamp = isAutoTimestamp;
        transaction.frameTimelineInfo = frameTimelineInfo;
    }

    void NotPlacedOnTransactionQueue(uint32_t flags) {
        ASSERT_TRUE(mFlinger.getTransactionQueue().isEmpty());
        EXPECT_CALL(*mFlinger.scheduler(), scheduleFrame()).Times(1);
        TransactionInfo transaction;
        setupSingle(transaction, flags,
                    /*desiredPresentTime*/ systemTime(), /*isAutoTimestamp*/ true,
                    FrameTimelineInfo{});
        nsecs_t applicationTime = systemTime();
        mFlinger.setTransactionState(transaction.frameTimelineInfo, transaction.states,
                                     transaction.displays, transaction.flags,
                                     transaction.applyToken, transaction.inputWindowCommands,
                                     transaction.desiredPresentTime, transaction.isAutoTimestamp,
                                     transaction.uncacheBuffers, mHasListenerCallbacks, mCallbacks,
                                     transaction.id, transaction.mergedTransactionIds);

        // If transaction is synchronous, SF applyTransactionState should time out (5s) wating for
        // SF to commit the transaction. If this is animation, it should not time out waiting.
        nsecs_t returnedTime = systemTime();
        EXPECT_LE(returnedTime, applicationTime + TRANSACTION_TIMEOUT);
        // Each transaction should have been placed on the transaction queue
        auto& transactionQueue = mFlinger.getTransactionQueue();
        EXPECT_FALSE(transactionQueue.isEmpty());
    }

    void PlaceOnTransactionQueue(uint32_t flags) {
        ASSERT_TRUE(mFlinger.getTransactionQueue().isEmpty());
        EXPECT_CALL(*mFlinger.scheduler(), scheduleFrame()).Times(1);

        // first check will see desired present time has not passed,
        // but afterwards it will look like the desired present time has passed
        nsecs_t time = systemTime();
        TransactionInfo transaction;
        setupSingle(transaction, flags, /*desiredPresentTime*/ time + s2ns(1), false,
                    FrameTimelineInfo{});
        nsecs_t applicationSentTime = systemTime();
        mFlinger.setTransactionState(transaction.frameTimelineInfo, transaction.states,
                                     transaction.displays, transaction.flags,
                                     transaction.applyToken, transaction.inputWindowCommands,
                                     transaction.desiredPresentTime, transaction.isAutoTimestamp,
                                     transaction.uncacheBuffers, mHasListenerCallbacks, mCallbacks,
                                     transaction.id, transaction.mergedTransactionIds);

        nsecs_t returnedTime = systemTime();
        EXPECT_LE(returnedTime, applicationSentTime + TRANSACTION_TIMEOUT);
        // This transaction should have been placed on the transaction queue
        auto& transactionQueue = mFlinger.getTransactionQueue();
        EXPECT_FALSE(transactionQueue.isEmpty());
    }

    void BlockedByPriorTransaction(uint32_t flags) {
        ASSERT_TRUE(mFlinger.getTransactionQueue().isEmpty());
        nsecs_t time = systemTime();
        EXPECT_CALL(*mFlinger.scheduler(), scheduleFrame()).Times(2);

        // transaction that should go on the pending thread
        TransactionInfo transactionA;
        setupSingle(transactionA, /*flags*/ 0, /*desiredPresentTime*/ time + s2ns(1), false,
                    FrameTimelineInfo{});

        // transaction that would not have gone on the pending thread if not
        // blocked
        TransactionInfo transactionB;
        setupSingle(transactionB, flags, /*desiredPresentTime*/ systemTime(),
                    /*isAutoTimestamp*/ true, FrameTimelineInfo{});

        nsecs_t applicationSentTime = systemTime();
        mFlinger.setTransactionState(transactionA.frameTimelineInfo, transactionA.states,
                                     transactionA.displays, transactionA.flags,
                                     transactionA.applyToken, transactionA.inputWindowCommands,
                                     transactionA.desiredPresentTime, transactionA.isAutoTimestamp,
                                     transactionA.uncacheBuffers, mHasListenerCallbacks, mCallbacks,
                                     transactionA.id, transactionA.mergedTransactionIds);

        // This thread should not have been blocked by the above transaction
        // (5s is the timeout period that applyTransactionState waits for SF to
        // commit the transaction)
        EXPECT_LE(systemTime(), applicationSentTime + TRANSACTION_TIMEOUT);
        // transaction that would goes to pending transaciton queue.
        mFlinger.flushTransactionQueues();

        applicationSentTime = systemTime();
        mFlinger.setTransactionState(transactionB.frameTimelineInfo, transactionB.states,
                                     transactionB.displays, transactionB.flags,
                                     transactionB.applyToken, transactionB.inputWindowCommands,
                                     transactionB.desiredPresentTime, transactionB.isAutoTimestamp,
                                     transactionB.uncacheBuffers, mHasListenerCallbacks, mCallbacks,
                                     transactionB.id, transactionB.mergedTransactionIds);

        // this thread should have been blocked by the above transaction
        // if this is an animation, this thread should be blocked for 5s
        // in setTransactionState waiting for transactionA to flush.  Otherwise,
        // the transaction should be placed on the pending queue
        EXPECT_LE(systemTime(), applicationSentTime + TRANSACTION_TIMEOUT);

        // transaction that would goes to pending transaciton queue.
        mFlinger.flushTransactionQueues();

        // check that the transaction was applied.
        auto transactionQueue = mFlinger.getPendingTransactionQueue();
        EXPECT_EQ(0u, transactionQueue.size());
    }

    void modulateVsync() {
        static_cast<void>(
                mFlinger.mutableScheduler().vsyncModulator().onRefreshRateChangeInitiated());
    }

    bool mHasListenerCallbacks = false;
    std::vector<ListenerCallbacks> mCallbacks;
    int mTransactionNumber = 0;
};

TEST_F(TransactionApplicationTest, AddToPendingQueue) {
    ASSERT_TRUE(mFlinger.getTransactionQueue().isEmpty());
    EXPECT_CALL(*mFlinger.scheduler(), scheduleFrame()).Times(1);

    TransactionInfo transactionA; // transaction to go on pending queue
    setupSingle(transactionA, /*flags*/ 0, /*desiredPresentTime*/ s2ns(1), false,
                FrameTimelineInfo{});
    mFlinger.setTransactionState(transactionA.frameTimelineInfo, transactionA.states,
                                 transactionA.displays, transactionA.flags, transactionA.applyToken,
                                 transactionA.inputWindowCommands, transactionA.desiredPresentTime,
                                 transactionA.isAutoTimestamp, transactionA.uncacheBuffers,
                                 mHasListenerCallbacks, mCallbacks, transactionA.id,
                                 transactionA.mergedTransactionIds);

    auto& transactionQueue = mFlinger.getTransactionQueue();
    ASSERT_FALSE(transactionQueue.isEmpty());

    auto transactionState = transactionQueue.pop().value();
    checkEqual(transactionA, transactionState);
}

TEST_F(TransactionApplicationTest, Flush_RemovesFromQueue) {
    ASSERT_TRUE(mFlinger.getTransactionQueue().isEmpty());
    EXPECT_CALL(*mFlinger.scheduler(), scheduleFrame()).Times(1);

    TransactionInfo transactionA; // transaction to go on pending queue
    setupSingle(transactionA, /*flags*/ 0, /*desiredPresentTime*/ s2ns(1), false,
                FrameTimelineInfo{});
    mFlinger.setTransactionState(transactionA.frameTimelineInfo, transactionA.states,
                                 transactionA.displays, transactionA.flags, transactionA.applyToken,
                                 transactionA.inputWindowCommands, transactionA.desiredPresentTime,
                                 transactionA.isAutoTimestamp, transactionA.uncacheBuffers,
                                 mHasListenerCallbacks, mCallbacks, transactionA.id,
                                 transactionA.mergedTransactionIds);

    auto& transactionQueue = mFlinger.getTransactionQueue();
    ASSERT_FALSE(transactionQueue.isEmpty());

    // because flushing uses the cached expected present time, we send an empty
    // transaction here (sending a null applyToken to fake it as from a
    // different process) to re-query and reset the cached expected present time
    TransactionInfo empty;
    empty.applyToken = sp<IBinder>();
    mFlinger.setTransactionState(empty.frameTimelineInfo, empty.states, empty.displays, empty.flags,
                                 empty.applyToken, empty.inputWindowCommands,
                                 empty.desiredPresentTime, empty.isAutoTimestamp,
                                 empty.uncacheBuffers, mHasListenerCallbacks, mCallbacks, empty.id,
                                 empty.mergedTransactionIds);

    // flush transaction queue should flush as desiredPresentTime has
    // passed
    mFlinger.flushTransactionQueues();

    EXPECT_TRUE(mFlinger.getTransactionQueue().isEmpty());
}

TEST_F(TransactionApplicationTest, NotPlacedOnTransactionQueue_SyncInputWindows) {
    NotPlacedOnTransactionQueue(/*flags*/ 0);
}

TEST_F(TransactionApplicationTest, PlaceOnTransactionQueue_SyncInputWindows) {
    PlaceOnTransactionQueue(/*flags*/ 0);
}

TEST_F(TransactionApplicationTest, FromHandle) {
    sp<IBinder> badHandle;
    auto ret = mFlinger.fromHandle(badHandle);
    EXPECT_EQ(nullptr, ret.get());
}

class FakeExternalTexture : public renderengine::ExternalTexture {
    const sp<GraphicBuffer> mEmptyBuffer = nullptr;
    uint32_t mWidth;
    uint32_t mHeight;
    uint64_t mId;
    PixelFormat mPixelFormat;
    uint64_t mUsage;

public:
    FakeExternalTexture(BufferData& bufferData)
          : mWidth(bufferData.getWidth()),
            mHeight(bufferData.getHeight()),
            mId(bufferData.getId()),
            mPixelFormat(bufferData.getPixelFormat()),
            mUsage(bufferData.getUsage()) {}
    const sp<GraphicBuffer>& getBuffer() const { return mEmptyBuffer; }
    bool hasSameBuffer(const renderengine::ExternalTexture& other) const override {
        return getId() == other.getId();
    }
    uint32_t getWidth() const override { return mWidth; }
    uint32_t getHeight() const override { return mHeight; }
    uint64_t getId() const override { return mId; }
    PixelFormat getPixelFormat() const override { return mPixelFormat; }
    uint64_t getUsage() const override { return mUsage; }
    void remapBuffer() override {}
    ~FakeExternalTexture() = default;
};

class LatchUnsignaledTest : public TransactionApplicationTest {
public:
    void TearDown() override {
        // Clear all transaction queues to release all transactions we sent
        // in the tests. Otherwise, gmock complains about memory leaks.
        while (!mFlinger.getTransactionQueue().isEmpty()) {
            mFlinger.getTransactionQueue().pop();
        }
        mFlinger.getPendingTransactionQueue().clear();
        mFlinger.commitTransactionsLocked(eTransactionMask);
        mFlinger.mutableCurrentState().layersSortedByZ.clear();
        mFlinger.mutableDrawingState().layersSortedByZ.clear();
    }

    static sp<Fence> fence(Fence::Status status) {
        const auto fence = sp<mock::MockFence>::make();
        EXPECT_CALL(*fence, getStatus()).WillRepeatedly(Return(status));
        return fence;
    }

    ComposerState createComposerState(int layerId, sp<Fence> fence, uint64_t what,
                                      std::optional<sp<IBinder>> layerHandle = std::nullopt) {
        ComposerState state;
        state.state.bufferData =
                std::make_shared<fake::BufferData>(/* bufferId */ 123L, /* width */ 1,
                                                   /* height */ 2, /* pixelFormat */ 0,
                                                   /* outUsage */ 0);
        state.state.bufferData->acquireFence = std::move(fence);
        state.state.layerId = layerId;
        state.state.surface = layerHandle.value_or(
                sp<Layer>::make(LayerCreationArgs(mFlinger.flinger(), nullptr, "TestLayer", 0, {}))
                        ->getHandle());
        state.state.bufferData->flags = BufferData::BufferDataChange::fenceChanged;

        state.state.what = what;
        if (what & layer_state_t::eCropChanged) {
            state.state.crop = Rect(1, 2, 3, 4);
        }
        if (what & layer_state_t::eFlagsChanged) {
            state.state.flags = layer_state_t::eEnableBackpressure;
            state.state.mask = layer_state_t::eEnableBackpressure;
        }

        return state;
    }

    TransactionInfo createTransactionInfo(const sp<IBinder>& applyToken,
                                          const std::vector<ComposerState>& states) {
        TransactionInfo transaction;
        const uint32_t kFlags = 0;
        const nsecs_t kDesiredPresentTime = systemTime();
        const bool kIsAutoTimestamp = true;
        const auto kFrameTimelineInfo = FrameTimelineInfo{};

        setupSingle(transaction, kFlags, kDesiredPresentTime, kIsAutoTimestamp, kFrameTimelineInfo);
        transaction.applyToken = applyToken;
        for (const auto& state : states) {
            transaction.states.push_back(state);
        }

        return transaction;
    }

    void setTransactionStates(const std::vector<TransactionInfo>& transactions,
                              size_t expectedTransactionsPending) {
        EXPECT_TRUE(mFlinger.getTransactionQueue().isEmpty());
        EXPECT_EQ(0u, mFlinger.getPendingTransactionQueue().size());

        for (auto transaction : transactions) {
            std::vector<ResolvedComposerState> resolvedStates;
            resolvedStates.reserve(transaction.states.size());
            for (auto& state : transaction.states) {
                ResolvedComposerState resolvedState;
                resolvedState.state = std::move(state.state);
                resolvedState.externalTexture =
                        std::make_shared<FakeExternalTexture>(*resolvedState.state.bufferData);
                resolvedStates.emplace_back(resolvedState);
            }

            TransactionState transactionState(transaction.frameTimelineInfo, resolvedStates,
                                              transaction.displays, transaction.flags,
                                              transaction.applyToken,
                                              transaction.inputWindowCommands,
                                              transaction.desiredPresentTime,
                                              transaction.isAutoTimestamp, {}, systemTime(),
                                              mHasListenerCallbacks, mCallbacks, getpid(),
                                              static_cast<int>(getuid()), transaction.id,
                                              transaction.mergedTransactionIds);
            mFlinger.setTransactionStateInternal(transactionState);
        }
        mFlinger.flushTransactionQueues();
        EXPECT_TRUE(mFlinger.getTransactionQueue().isEmpty());
        EXPECT_EQ(expectedTransactionsPending, mFlinger.getPendingTransactionCount());
    }
};

class LatchUnsignaledAutoSingleLayerTest : public LatchUnsignaledTest {
public:
    void SetUp() override {
        LatchUnsignaledTest::SetUp();
        SurfaceFlinger::enableLatchUnsignaledConfig = LatchUnsignaledConfig::AutoSingleLayer;
    }
};

TEST_F(LatchUnsignaledAutoSingleLayerTest, Flush_RemovesSingleSignaledFromTheQueue) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 0u;

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {createComposerState(kLayerId, fence(Fence::Status::Signaled),
                                                       layer_state_t::eBufferChanged)});
    setTransactionStates({signaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, Flush_RemovesSingleUnSignaledFromTheQueue) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 0u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, Flush_KeepsUnSignaledInTheQueue_NonBufferCropChange) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eCropChanged |
                                                                      layer_state_t::
                                                                              eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, Flush_KeepsUnSignaledInTheQueue_NonBufferChangeClubed) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eCropChanged |
                                                                      layer_state_t::
                                                                              eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, Flush_KeepsInTheQueueSameApplyTokenMultiState) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 1u;

    const auto mixedTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({mixedTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, Flush_KeepsInTheQueue_MultipleStateTransaction) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 1u;

    const auto mixedTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({mixedTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, Flush_RemovesSignaledFromTheQueue) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 0u;

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto signaledTransaction2 =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({signaledTransaction, signaledTransaction2}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest,
       UnsignaledNotAppliedWhenThereAreSignaled_UnsignaledFirst) {
    const sp<IBinder> kApplyToken1 =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const sp<IBinder> kApplyToken2 = sp<BBinder>::make();
    const sp<IBinder> kApplyToken3 = sp<BBinder>::make();
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken1,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken2,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto signaledTransaction2 =
            createTransactionInfo(kApplyToken3,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });

    setTransactionStates({unsignaledTransaction, signaledTransaction, signaledTransaction2},
                         kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, Flush_KeepsTransactionInTheQueueSameApplyToken) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto signaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction, signaledTransaction},
                         kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, Flush_KeepsTransactionInTheQueue) {
    const sp<IBinder> kApplyToken1 =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const sp<IBinder> kApplyToken2 = sp<BBinder>::make();
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken1,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto unsignaledTransaction2 =
            createTransactionInfo(kApplyToken2,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction, unsignaledTransaction2},
                         kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, DontLatchUnsignaledWhenEarlyOffset) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });

    modulateVsync();
    setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAutoSingleLayerTest, UnsignaledNotAppliedWhenThereAreSignaled_SignaledFirst) {
    const sp<IBinder> kApplyToken1 =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const sp<IBinder> kApplyToken2 = sp<BBinder>::make();
    const sp<IBinder> kApplyToken3 = sp<BBinder>::make();
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 1u;

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken1,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto signaledTransaction2 =
            createTransactionInfo(kApplyToken2,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken3,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });

    setTransactionStates({signaledTransaction, signaledTransaction2, unsignaledTransaction},
                         kExpectedTransactionsPending);
}

class LatchUnsignaledDisabledTest : public LatchUnsignaledTest {
public:
    void SetUp() override {
        LatchUnsignaledTest::SetUp();
        SurfaceFlinger::enableLatchUnsignaledConfig = LatchUnsignaledConfig::Disabled;
    }
};

TEST_F(LatchUnsignaledDisabledTest, Flush_RemovesSignaledFromTheQueue) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 0u;

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {createComposerState(kLayerId, fence(Fence::Status::Signaled),
                                                       layer_state_t::eBufferChanged)});
    setTransactionStates({signaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledDisabledTest, Flush_KeepsInTheQueue) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledDisabledTest, Flush_KeepsInTheQueueSameLayerId) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledDisabledTest, Flush_KeepsInTheQueueDifferentLayerId) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledDisabledTest, Flush_RemovesSignaledFromTheQueue_MultipleLayers) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 0u;

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto signaledTransaction2 =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({signaledTransaction, signaledTransaction2}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledDisabledTest, Flush_KeepInTheQueueDifferentApplyToken) {
    const sp<IBinder> kApplyToken1 =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const sp<IBinder> kApplyToken2 = sp<BBinder>::make();
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 1u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken1,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto signaledTransaction =
            createTransactionInfo(kApplyToken2,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction, signaledTransaction},
                         kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledDisabledTest, Flush_KeepInTheQueueSameApplyToken) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 1u;

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({signaledTransaction, unsignaledTransaction},
                         kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledDisabledTest, Flush_KeepInTheUnsignaledTheQueue) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 2u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto unsignaledTransaction2 =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction, unsignaledTransaction2},
                         kExpectedTransactionsPending);
}

class LatchUnsignaledAlwaysTest : public LatchUnsignaledTest {
public:
    void SetUp() override {
        LatchUnsignaledTest::SetUp();
        SurfaceFlinger::enableLatchUnsignaledConfig = LatchUnsignaledConfig::Always;
    }
};

TEST_F(LatchUnsignaledAlwaysTest, Flush_RemovesSignaledFromTheQueue) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 0u;

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {createComposerState(kLayerId, fence(Fence::Status::Signaled),
                                                       layer_state_t::eBufferChanged)});
    setTransactionStates({signaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAlwaysTest, Flush_RemovesFromTheQueue) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 0u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {createComposerState(kLayerId, fence(Fence::Status::Unsignaled),
                                                       layer_state_t::eBufferChanged)});
    setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAlwaysTest, Flush_RemovesFromTheQueueSameLayerId) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 0u;

    const auto mixedTransaction =
            createTransactionInfo(kApplyToken,
                                  {createComposerState(kLayerId, fence(Fence::Status::Unsignaled),
                                                       layer_state_t::eBufferChanged),
                                   createComposerState(kLayerId, fence(Fence::Status::Signaled),
                                                       layer_state_t::eBufferChanged)});
    setTransactionStates({mixedTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAlwaysTest, Flush_RemovesFromTheQueueDifferentLayerId) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 0u;

    const auto mixedTransaction =
            createTransactionInfo(kApplyToken,
                                  {createComposerState(kLayerId1, fence(Fence::Status::Unsignaled),
                                                       layer_state_t::eBufferChanged),
                                   createComposerState(kLayerId2, fence(Fence::Status::Signaled),
                                                       layer_state_t::eBufferChanged)});
    setTransactionStates({mixedTransaction}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAlwaysTest, Flush_RemovesSignaledFromTheQueue_MultipleLayers) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 0u;

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto signaledTransaction2 =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({signaledTransaction, signaledTransaction2}, kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAlwaysTest, Flush_RemovesFromTheQueueDifferentApplyToken) {
    const sp<IBinder> kApplyToken1 =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const sp<IBinder> kApplyToken2 = sp<BBinder>::make();
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 0u;

    const auto signaledTransaction =
            createTransactionInfo(kApplyToken1,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken2,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({signaledTransaction, unsignaledTransaction},
                         kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAlwaysTest, Flush_RemovesUnsignaledFromTheQueueSameApplyToken) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 0u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto signaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Signaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction, signaledTransaction},
                         kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAlwaysTest, Flush_RemovesUnsignaledFromTheQueue) {
    const sp<IBinder> kApplyToken1 =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const sp<IBinder> kApplyToken2 = sp<BBinder>::make();
    const auto kLayerId1 = 1;
    const auto kLayerId2 = 2;
    const auto kExpectedTransactionsPending = 0u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken1,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    const auto unsignaledTransaction2 =
            createTransactionInfo(kApplyToken2,
                                  {
                                          createComposerState(kLayerId2,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });
    setTransactionStates({unsignaledTransaction, unsignaledTransaction2},
                         kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAlwaysTest, RespectsBackPressureFlag) {
    const sp<IBinder> kApplyToken1 =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const sp<IBinder> kApplyToken2 = sp<BBinder>::make();
    const auto kLayerId1 = 1;
    const auto kExpectedTransactionsPending = 1u;
    auto layer =
            sp<Layer>::make(LayerCreationArgs(mFlinger.flinger(), nullptr, "TestLayer", 0, {}));
    auto layerHandle = layer->getHandle();
    const auto setBackPressureFlagTransaction =
            createTransactionInfo(kApplyToken1,
                                  {createComposerState(kLayerId1, fence(Fence::Status::Unsignaled),
                                                       layer_state_t::eBufferChanged |
                                                               layer_state_t::eFlagsChanged,
                                                       {layerHandle})});
    setTransactionStates({setBackPressureFlagTransaction}, 0u);

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken1,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged,
                                                              {layerHandle}),
                                  });
    const auto unsignaledTransaction2 =
            createTransactionInfo(kApplyToken1,
                                  {
                                          createComposerState(kLayerId1,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged,
                                                              {layerHandle}),
                                  });
    setTransactionStates({unsignaledTransaction, unsignaledTransaction2},
                         kExpectedTransactionsPending);
}

TEST_F(LatchUnsignaledAlwaysTest, LatchUnsignaledWhenEarlyOffset) {
    const sp<IBinder> kApplyToken =
            IInterface::asBinder(TransactionCompletedListener::getIInstance());
    const auto kLayerId = 1;
    const auto kExpectedTransactionsPending = 0u;

    const auto unsignaledTransaction =
            createTransactionInfo(kApplyToken,
                                  {
                                          createComposerState(kLayerId,
                                                              fence(Fence::Status::Unsignaled),
                                                              layer_state_t::eBufferChanged),
                                  });

    modulateVsync();
    setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
}

TEST(TransactionHandlerTest, QueueTransaction) {
    TransactionHandler handler;
    TransactionState transaction;
    transaction.applyToken = sp<BBinder>::make();
    transaction.id = 42;
    handler.queueTransaction(std::move(transaction));
    handler.collectTransactions();
    std::vector<TransactionState> transactionsReadyToBeApplied = handler.flushTransactions();

    EXPECT_EQ(transactionsReadyToBeApplied.size(), 1u);
    EXPECT_EQ(transactionsReadyToBeApplied.front().id, 42u);
}

TEST(TransactionHandlerTest, TransactionsKeepTrackOfDirectMerges) {
    SurfaceComposerClient::Transaction transaction1, transaction2, transaction3, transaction4;

    uint64_t transaction2Id = transaction2.getId();
    uint64_t transaction3Id = transaction3.getId();
    EXPECT_NE(transaction2Id, transaction3Id);

    transaction1.merge(std::move(transaction2));
    transaction1.merge(std::move(transaction3));

    EXPECT_EQ(transaction1.getMergedTransactionIds().size(), 2u);
    EXPECT_EQ(transaction1.getMergedTransactionIds()[0], transaction3Id);
    EXPECT_EQ(transaction1.getMergedTransactionIds()[1], transaction2Id);
}

TEST(TransactionHandlerTest, TransactionsKeepTrackOfIndirectMerges) {
    SurfaceComposerClient::Transaction transaction1, transaction2, transaction3, transaction4;

    uint64_t transaction2Id = transaction2.getId();
    uint64_t transaction3Id = transaction3.getId();
    uint64_t transaction4Id = transaction4.getId();
    EXPECT_NE(transaction2Id, transaction3Id);
    EXPECT_NE(transaction2Id, transaction4Id);
    EXPECT_NE(transaction3Id, transaction4Id);

    transaction4.merge(std::move(transaction2));
    transaction4.merge(std::move(transaction3));

    EXPECT_EQ(transaction4.getMergedTransactionIds().size(), 2u);
    EXPECT_EQ(transaction4.getMergedTransactionIds()[0], transaction3Id);
    EXPECT_EQ(transaction4.getMergedTransactionIds()[1], transaction2Id);

    transaction1.merge(std::move(transaction4));

    EXPECT_EQ(transaction1.getMergedTransactionIds().size(), 3u);
    EXPECT_EQ(transaction1.getMergedTransactionIds()[0], transaction4Id);
    EXPECT_EQ(transaction1.getMergedTransactionIds()[1], transaction3Id);
    EXPECT_EQ(transaction1.getMergedTransactionIds()[2], transaction2Id);
}

TEST(TransactionHandlerTest, TransactionMergesAreCleared) {
    SurfaceComposerClient::Transaction transaction1, transaction2, transaction3;

    transaction1.merge(std::move(transaction2));
    transaction1.merge(std::move(transaction3));

    EXPECT_EQ(transaction1.getMergedTransactionIds().size(), 2u);

    transaction1.clear();

    EXPECT_EQ(transaction1.getMergedTransactionIds().empty(), true);
}

TEST(TransactionHandlerTest, TransactionMergesAreCapped) {
    SurfaceComposerClient::Transaction transaction;
    std::vector<uint64_t> mergedTransactionIds;

    for (uint i = 0; i < 20u; i++) {
        SurfaceComposerClient::Transaction transactionToMerge;
        mergedTransactionIds.push_back(transactionToMerge.getId());
        transaction.merge(std::move(transactionToMerge));
    }

    // Keeps latest 10 merges in order of merge recency
    EXPECT_EQ(transaction.getMergedTransactionIds().size(), 10u);
    for (uint i = 0; i < 10u; i++) {
        EXPECT_EQ(transaction.getMergedTransactionIds()[i],
                  mergedTransactionIds[mergedTransactionIds.size() - 1 - i]);
    }
}

TEST(TransactionHandlerTest, KeepsMergesFromMoreRecentMerge) {
    SurfaceComposerClient::Transaction transaction1, transaction2, transaction3;
    std::vector<uint64_t> mergedTransactionIds1, mergedTransactionIds2, mergedTransactionIds3;
    uint64_t transaction2Id = transaction2.getId();
    uint64_t transaction3Id = transaction3.getId();

    for (uint i = 0; i < 20u; i++) {
        SurfaceComposerClient::Transaction transactionToMerge;
        mergedTransactionIds1.push_back(transactionToMerge.getId());
        transaction1.merge(std::move(transactionToMerge));
    }

    for (uint i = 0; i < 5u; i++) {
        SurfaceComposerClient::Transaction transactionToMerge;
        mergedTransactionIds2.push_back(transactionToMerge.getId());
        transaction2.merge(std::move(transactionToMerge));
    }

    transaction1.merge(std::move(transaction2));
    EXPECT_EQ(transaction1.getMergedTransactionIds().size(), 10u);
    EXPECT_EQ(transaction1.getMergedTransactionIds()[0], transaction2Id);
    for (uint i = 0; i < 5u; i++) {
        EXPECT_EQ(transaction1.getMergedTransactionIds()[i + 1u],
                  mergedTransactionIds2[mergedTransactionIds2.size() - 1 - i]);
    }
    for (uint i = 0; i < 4u; i++) {
        EXPECT_EQ(transaction1.getMergedTransactionIds()[i + 6u],
                  mergedTransactionIds1[mergedTransactionIds1.size() - 1 - i]);
    }

    for (uint i = 0; i < 20u; i++) {
        SurfaceComposerClient::Transaction transactionToMerge;
        mergedTransactionIds3.push_back(transactionToMerge.getId());
        transaction3.merge(std::move(transactionToMerge));
    }

    transaction1.merge(std::move(transaction3));
    EXPECT_EQ(transaction1.getMergedTransactionIds().size(), 10u);
    EXPECT_EQ(transaction1.getMergedTransactionIds()[0], transaction3Id);
    for (uint i = 0; i < 9u; i++) {
        EXPECT_EQ(transaction1.getMergedTransactionIds()[i + 1],
                  mergedTransactionIds3[mergedTransactionIds3.size() - 1 - i]);
    }
}

TEST(TransactionHandlerTest, CanAddTransactionWithFullMergedIds) {
    SurfaceComposerClient::Transaction transaction1, transaction2;
    for (uint i = 0; i < 20u; i++) {
        SurfaceComposerClient::Transaction transactionToMerge;
        transaction1.merge(std::move(transactionToMerge));
    }

    EXPECT_EQ(transaction1.getMergedTransactionIds().size(), 10u);

    auto transaction1Id = transaction1.getId();
    transaction2.merge(std::move(transaction1));
    EXPECT_EQ(transaction2.getMergedTransactionIds().size(), 10u);
    auto mergedTransactionIds = transaction2.getMergedTransactionIds();
    EXPECT_TRUE(std::count(mergedTransactionIds.begin(), mergedTransactionIds.end(),
                           transaction1Id) > 0);
}

} // namespace android