Add Unit Tests (facebook#53913)

Summary:
Pull Request resolved: facebook#53913

Changelog: [Internal]

Reviewed By: rshest

Differential Revision: D83091947

fbshipit-source-id: 63baf543b180070591d4779b1203909359aec132

Author: christophpurrer

packages/react-native/ReactCxxPlatform/react/threading/TaskDispatchThread.cpp

@@ -73,6 +73,9 @@ void TaskDispatchThread::runAsync(
 }
 
 void TaskDispatchThread::runSync(TaskFn&& task) noexcept {
+  if (!running_) {
+    return;
+  }
   std::promise<void> promise;
   runAsync([&]() {
     if (running_) {

packages/react-native/ReactCxxPlatform/react/threading/tests/.clang-tidy

@@ -0,0 +1,5 @@
+---
+InheritParentConfig: true
+Checks: '
+-facebook-hte-BadCall-sleep_for,
+'

packages/react-native/ReactCxxPlatform/react/threading/tests/TaskDispatchThreadTests.cpp

@@ -0,0 +1,130 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include <gtest/gtest.h>
+#include <react/threading/TaskDispatchThread.h>
+#include <atomic>
+#include <chrono>
+#include <thread>
+
+namespace facebook::react {
+
+class TaskDispatchThreadTest : public ::testing::Test {
+ protected:
+  TaskDispatchThread dispatcher;
+};
+
+// Test: isOnThread returns true inside the looper thread
+TEST_F(TaskDispatchThreadTest, IsOnThreadReturnsTrueInLooper) {
+  bool result = false;
+  dispatcher.runSync([&] { result = dispatcher.isOnThread(); });
+  EXPECT_TRUE(result);
+}
+
+// Test: isRunning returns true before quit, false after
+TEST_F(TaskDispatchThreadTest, IsRunningFlag) {
+  EXPECT_TRUE(dispatcher.isRunning());
+  dispatcher.quit();
+  EXPECT_FALSE(dispatcher.isRunning());
+}
+
+// Test: runAsync executes the task
+TEST_F(TaskDispatchThreadTest, RunAsyncExecutesTask) {
+  std::atomic<int> counter{0};
+  dispatcher.runAsync([&] { counter++; });
+  // Wait for task to complete
+  std::this_thread::sleep_for(std::chrono::milliseconds(50));
+  EXPECT_EQ(counter.load(), 1);
+}
+
+// Test: runSync executes the task and blocks until done
+TEST_F(TaskDispatchThreadTest, RunSyncExecutesTask) {
+  std::atomic<int> counter{0};
+  dispatcher.runSync([&] { counter++; });
+  EXPECT_EQ(counter.load(), 1);
+}
+
+// Test: runAsync with delay
+TEST_F(TaskDispatchThreadTest, RunAsyncWithDelay) {
+  std::atomic<int> counter{0};
+  dispatcher.runAsync([&] { counter++; }, std::chrono::milliseconds(100));
+  std::this_thread::sleep_for(std::chrono::milliseconds(50));
+  EXPECT_EQ(counter.load(), 0); // Not yet executed
+  std::this_thread::sleep_for(std::chrono::milliseconds(70));
+  EXPECT_EQ(counter.load(), 1); // Should be executed now
+}
+
+// Test: Multiple delayed tasks execute in order
+TEST_F(TaskDispatchThreadTest, MultipleDelayedTasksOrder) {
+  std::vector<int> results;
+  dispatcher.runAsync(
+      [&] { results.push_back(1); }, std::chrono::milliseconds(50));
+  dispatcher.runAsync(
+      [&] { results.push_back(2); }, std::chrono::milliseconds(100));
+  std::this_thread::sleep_for(std::chrono::milliseconds(120));
+  ASSERT_EQ(results.size(), 2);
+  EXPECT_EQ(results[0], 1);
+  EXPECT_EQ(results[1], 2);
+}
+
+// Test: runSync blocks until task is done
+TEST_F(TaskDispatchThreadTest, RunSyncBlocksUntilDone) {
+  std::atomic<bool> started{false};
+  std::atomic<bool> finished{false};
+  dispatcher.runAsync([&] {
+    started = true;
+    std::this_thread::sleep_for(std::chrono::milliseconds(50));
+    finished = true;
+  });
+  dispatcher.runSync([&] {
+    EXPECT_TRUE(started);
+    EXPECT_TRUE(finished);
+  });
+}
+
+// Test: quit prevents further tasks from running
+TEST_F(TaskDispatchThreadTest, QuitPreventsFurtherTasks) {
+  dispatcher.quit();
+  std::atomic<int> counter{0};
+  dispatcher.runAsync([&] { counter++; });
+  std::this_thread::sleep_for(std::chrono::milliseconds(50));
+  EXPECT_EQ(counter.load(), 0);
+}
+
+// Test: Multiple runSync tasks execute serially
+TEST_F(TaskDispatchThreadTest, MultipleRunSyncSerialExecution) {
+  std::vector<int> results;
+  dispatcher.runSync([&] { results.push_back(1); });
+  dispatcher.runSync([&] { results.push_back(2); });
+  EXPECT_EQ(results.size(), 2);
+  EXPECT_EQ(results[0], 1);
+  EXPECT_EQ(results[1], 2);
+}
+
+// Test: Edge case - runSync after quit should not execute
+TEST_F(TaskDispatchThreadTest, RunSyncAfterQuitDoesNotExecute) {
+  dispatcher.quit();
+  std::atomic<int> counter{0};
+  dispatcher.runSync([&] { counter++; });
+  EXPECT_EQ(counter.load(), 0);
+}
+
+// Test: Thread safety - runAsync from multiple threads
+TEST_F(TaskDispatchThreadTest, RunAsyncFromMultipleThreads) {
+  std::atomic<int> counter{0};
+  auto task = [&] { dispatcher.runAsync([&] { counter++; }); };
+  std::thread t1(task);
+  std::thread t2(task);
+  std::thread t3(task);
+  t1.join();
+  t2.join();
+  t3.join();
+  std::this_thread::sleep_for(std::chrono::milliseconds(100));
+  EXPECT_EQ(counter.load(), 3);
+}
+
+} // namespace facebook::react