Add unit tests for HintSessionWrapper

This patch adds several unit tests for HintSessionWrapper, including
one specifically for a recent race condition memory leak.

It also refactors HintSessionWrapper to better support testing, and
creates a macro to shorten the dlsym bindings.

Bug: 299541959
Test: hwuiunit

Change-Id: I05ed15cdbd157b109667563d30627cfc4ae83777
diff --git a/libs/hwui/tests/unit/HintSessionWrapperTests.cpp b/libs/hwui/tests/unit/HintSessionWrapperTests.cpp
new file mode 100644
index 0000000..623be1e
--- /dev/null
+++ b/libs/hwui/tests/unit/HintSessionWrapperTests.cpp
@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+#include <private/performance_hint_private.h>
+#include <renderthread/HintSessionWrapper.h>
+#include <utils/Log.h>
+
+#include <chrono>
+
+#include "Properties.h"
+
+using namespace testing;
+using namespace std::chrono_literals;
+
+APerformanceHintManager* managerPtr = reinterpret_cast<APerformanceHintManager*>(123);
+APerformanceHintSession* sessionPtr = reinterpret_cast<APerformanceHintSession*>(456);
+int uiThreadId = 1;
+int renderThreadId = 2;
+
+namespace android::uirenderer::renderthread {
+
+class HintSessionWrapperTests : public testing::Test {
+public:
+    void SetUp() override;
+    void TearDown() override;
+
+protected:
+    std::shared_ptr<HintSessionWrapper> mWrapper;
+
+    class MockHintSessionBinding : public HintSessionWrapper::HintSessionBinding {
+    public:
+        void init() override;
+
+        MOCK_METHOD(APerformanceHintManager*, fakeGetManager, ());
+        MOCK_METHOD(APerformanceHintSession*, fakeCreateSession,
+                    (APerformanceHintManager*, const int32_t*, size_t, int64_t));
+        MOCK_METHOD(void, fakeCloseSession, (APerformanceHintSession*));
+        MOCK_METHOD(void, fakeUpdateTargetWorkDuration, (APerformanceHintSession*, int64_t));
+        MOCK_METHOD(void, fakeReportActualWorkDuration, (APerformanceHintSession*, int64_t));
+        MOCK_METHOD(void, fakeSendHint, (APerformanceHintSession*, int32_t));
+    };
+
+    // Must be static so it can have function pointers we can point to with static methods
+    static std::shared_ptr<MockHintSessionBinding> sMockBinding;
+
+    // Must be static so we can point to them as normal fn pointers with HintSessionBinding
+    static APerformanceHintManager* stubGetManager() { return sMockBinding->fakeGetManager(); };
+    static APerformanceHintSession* stubCreateSession(APerformanceHintManager* manager,
+                                                      const int32_t* ids, size_t idsSize,
+                                                      int64_t initialTarget) {
+        return sMockBinding->fakeCreateSession(manager, ids, idsSize, initialTarget);
+    }
+    static APerformanceHintSession* stubSlowCreateSession(APerformanceHintManager* manager,
+                                                          const int32_t* ids, size_t idsSize,
+                                                          int64_t initialTarget) {
+        std::this_thread::sleep_for(50ms);
+        return sMockBinding->fakeCreateSession(manager, ids, idsSize, initialTarget);
+    }
+    static void stubCloseSession(APerformanceHintSession* session) {
+        sMockBinding->fakeCloseSession(session);
+    };
+    static void stubUpdateTargetWorkDuration(APerformanceHintSession* session,
+                                             int64_t workDuration) {
+        sMockBinding->fakeUpdateTargetWorkDuration(session, workDuration);
+    }
+    static void stubReportActualWorkDuration(APerformanceHintSession* session,
+                                             int64_t workDuration) {
+        sMockBinding->fakeReportActualWorkDuration(session, workDuration);
+    }
+    static void stubSendHint(APerformanceHintSession* session, int32_t hintId) {
+        sMockBinding->fakeSendHint(session, hintId);
+    };
+    void waitForWrapperReady() { mWrapper->mHintSessionFuture.wait(); }
+};
+
+std::shared_ptr<HintSessionWrapperTests::MockHintSessionBinding>
+        HintSessionWrapperTests::sMockBinding;
+
+void HintSessionWrapperTests::SetUp() {
+    // Pretend it's supported even if we're in an emulator
+    Properties::useHintManager = true;
+    sMockBinding = std::make_shared<NiceMock<MockHintSessionBinding>>();
+    mWrapper = std::make_shared<HintSessionWrapper>(uiThreadId, renderThreadId);
+    mWrapper->mBinding = sMockBinding;
+    EXPECT_CALL(*sMockBinding, fakeGetManager).WillOnce(Return(managerPtr));
+    ON_CALL(*sMockBinding, fakeCreateSession).WillByDefault(Return(sessionPtr));
+}
+
+void HintSessionWrapperTests::MockHintSessionBinding::init() {
+    sMockBinding->getManager = &stubGetManager;
+    if (sMockBinding->createSession == nullptr) {
+        sMockBinding->createSession = &stubCreateSession;
+    }
+    sMockBinding->closeSession = &stubCloseSession;
+    sMockBinding->updateTargetWorkDuration = &stubUpdateTargetWorkDuration;
+    sMockBinding->reportActualWorkDuration = &stubReportActualWorkDuration;
+    sMockBinding->sendHint = &stubSendHint;
+}
+
+void HintSessionWrapperTests::TearDown() {
+    mWrapper = nullptr;
+    sMockBinding = nullptr;
+}
+
+TEST_F(HintSessionWrapperTests, destructorClosesBackgroundSession) {
+    EXPECT_CALL(*sMockBinding, fakeCloseSession(sessionPtr)).Times(1);
+    sMockBinding->createSession = stubSlowCreateSession;
+    mWrapper->init();
+    mWrapper = nullptr;
+}
+
+TEST_F(HintSessionWrapperTests, sessionInitializesCorrectly) {
+    EXPECT_CALL(*sMockBinding, fakeCreateSession(managerPtr, _, Gt(1), _)).Times(1);
+    mWrapper->init();
+    waitForWrapperReady();
+}
+
+TEST_F(HintSessionWrapperTests, loadUpHintsSendCorrectly) {
+    EXPECT_CALL(*sMockBinding,
+                fakeSendHint(sessionPtr, static_cast<int32_t>(SessionHint::CPU_LOAD_UP)))
+            .Times(1);
+    mWrapper->init();
+    waitForWrapperReady();
+    mWrapper->sendLoadIncreaseHint();
+}
+
+TEST_F(HintSessionWrapperTests, loadResetHintsSendCorrectly) {
+    EXPECT_CALL(*sMockBinding,
+                fakeSendHint(sessionPtr, static_cast<int32_t>(SessionHint::CPU_LOAD_RESET)))
+            .Times(1);
+    mWrapper->init();
+    waitForWrapperReady();
+    mWrapper->sendLoadResetHint();
+}
+
+}  // namespace android::uirenderer::renderthread
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