Implemented submittable_executor and some other missed files

A file was named wrong. It was changed.

internal/platform/implementation/linux/device_info_test.cc

@@ -0,0 +1,129 @@
+// Copyright 2021 Google LLC
+//
+// 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
+//
+//     https://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 "internal/platform/implementation/linux/device_info.h"
+
+#include <functional>
+#include <string>
+
+#include "gtest/gtest.h"
+#include "absl/synchronization/notification.h"
+#include "internal/platform/implementation/device_info.h"
+
+namespace nearby {
+namespace linux {
+namespace {
+
+TEST(DeviceInfo, DISABLED_GetComputerName) {
+  EXPECT_TRUE(DeviceInfo().GetOsDeviceName().has_value());
+}
+
+TEST(DeviceInfo, DISABLED_GetDeviceType) {
+  EXPECT_EQ(DeviceInfo().GetDeviceType(), api::DeviceInfo::DeviceType::kLaptop);
+}
+
+TEST(DeviceInfo, GetOsType) {
+  EXPECT_EQ(DeviceInfo().GetOsType(), api::DeviceInfo::OsType::kLinux);
+}
+
+TEST(DeviceInfo, DISABLED_GetFullName) {
+  EXPECT_TRUE(DeviceInfo().GetFullName().has_value());
+}
+
+TEST(DeviceInfo, DISABLED_GetGivenName) {
+  EXPECT_TRUE(DeviceInfo().GetGivenName().has_value());
+}
+
+TEST(DeviceInfo, DISABLED_GetLastName) {
+  EXPECT_TRUE(DeviceInfo().GetLastName().has_value());
+}
+
+TEST(DeviceInfo, DISABLED_GetProfileUserName) {
+  EXPECT_TRUE(DeviceInfo().GetProfileUserName().has_value());
+}
+
+TEST(DeviceInfo, DISABLED_GetLocalAppDataPath) {
+  EXPECT_TRUE(DeviceInfo().GetLocalAppDataPath().has_value());
+}
+
+TEST(DeviceInfo, DISABLED_GetDownloadPath) {
+  EXPECT_TRUE(DeviceInfo().GetDownloadPath().has_value());
+}
+
+TEST(DeviceInfo, DISABLED_GetTemporaryPath) {
+  EXPECT_TRUE(DeviceInfo().GetTemporaryPath().has_value());
+}
+
+TEST(DeviceInfo, DISABLED_IsScreenLocked) {
+  EXPECT_FALSE(DeviceInfo().IsScreenLocked());
+}
+
+TEST(DeviceInfo, DISABLED_RegisterScreenLockedListener) {
+  std::function<void(api::DeviceInfo::ScreenStatus)> listener_1 =
+      [](api::DeviceInfo::ScreenStatus) {};
+  std::function<void(api::DeviceInfo::ScreenStatus)> listener_2 =
+      [](api::DeviceInfo::ScreenStatus) {};
+
+  DeviceInfo device_info;
+  EXPECT_EQ(device_info.screen_locked_listeners_.size(), 0);
+
+  device_info.RegisterScreenLockedListener("listener_1", listener_1);
+  EXPECT_EQ(device_info.screen_locked_listeners_.size(), 1);
+
+  device_info.RegisterScreenLockedListener("listener_2", listener_2);
+  EXPECT_EQ(device_info.screen_locked_listeners_.size(), 2);
+}
+
+TEST(DeviceInfo, DISABLED_UnregisterScreenLockedListener) {
+  std::function<void(api::DeviceInfo::ScreenStatus)> listener_1 =
+      [](api::DeviceInfo::ScreenStatus) {};
+  std::function<void(api::DeviceInfo::ScreenStatus)> listener_2 =
+      [](api::DeviceInfo::ScreenStatus) {};
+
+  DeviceInfo device_info;
+  EXPECT_EQ(device_info.screen_locked_listeners_.size(), 0);
+
+  device_info.RegisterScreenLockedListener("listener_1", listener_1);
+  device_info.RegisterScreenLockedListener("listener_2", listener_2);
+  EXPECT_EQ(device_info.screen_locked_listeners_.size(), 2);
+
+  device_info.UnregisterScreenLockedListener("listener_1");
+  EXPECT_EQ(device_info.screen_locked_listeners_.size(), 1);
+
+  device_info.UnregisterScreenLockedListener("listener_2");
+  EXPECT_EQ(device_info.screen_locked_listeners_.size(), 0);
+}
+
+TEST(DeviceInfo, DISABLED_UpdateScreenLockedListener) {
+  absl::Notification notification;
+
+  api::DeviceInfo::ScreenStatus screen_locked_tracker =
+      api::DeviceInfo::ScreenStatus::kUndetermined;
+
+  std::function<void(api::DeviceInfo::ScreenStatus)> listener =
+      [&screen_locked_tracker,
+       &notification](api::DeviceInfo::ScreenStatus status) {
+        screen_locked_tracker = api::DeviceInfo::ScreenStatus::kLocked;
+        notification.Notify();
+      };
+
+  DeviceInfo device_info;
+  device_info.RegisterScreenLockedListener("listener", listener);
+  EXPECT_TRUE(notification.WaitForNotificationWithTimeout(absl::Seconds(5)));
+  EXPECT_EQ(screen_locked_tracker, api::DeviceInfo::ScreenStatus::kLocked);
+}
+
+}  // namespace
+}  // namespace linux
+}  // namespace nearby

internal/platform/implementation/linux/scheduled_executor_test.cc

@@ -0,0 +1,179 @@
+// Copyright 2021 Google LLC
+//
+// 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
+//
+//     https://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 "internal/platform/implementation/linux/scheduled_executor.h"
+
+#include <memory>
+#include <utility>
+
+#include "gtest/gtest.h"
+#include "absl/synchronization/notification.h"
+#include "absl/time/clock.h"
+#include "absl/time/time.h"
+#include "internal/platform/implementation/linux/test_data.h"
+
+namespace nearby {
+namespace linux {
+namespace {
+
+TEST(ScheduledExecutorTests, ExecuteSucceeds) {
+  absl::Notification notification;
+  // Arrange
+  std::string expected(RUNNABLE_0_TEXT.c_str());
+
+  auto submittableExecutor = std::make_unique<ScheduledExecutor>();
+  std::string output = std::string();
+  // Container to note threads that ran
+  std::unique_ptr<std::vector<std::thread::id>> threadIds =
+      std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  // Act
+  submittableExecutor->Execute([&]() {
+    threadIds->push_back(std::this_thread::get_id());
+    output.append(RUNNABLE_0_TEXT.c_str());
+    notification.Notify();
+  });
+
+  ASSERT_TRUE(
+      notification.WaitForNotificationWithTimeout(absl::Milliseconds(200)));
+  submittableExecutor->Shutdown();
+
+  //  Assert
+  //  We should've run 1 time on the main thread, and 1 times on the
+  //  workerThread
+  ASSERT_EQ(threadIds->size(), 2);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  ASSERT_EQ(output, expected);
+}
+
+TEST(ScheduledExecutorTests, ScheduleSucceeds) {
+  absl::Notification notification;
+  // Arrange
+  std::string expected(RUNNABLE_0_TEXT.c_str());
+
+  auto submittableExecutor = std::make_unique<ScheduledExecutor>();
+  std::string output = std::string();
+  // Container to note threads that ran
+  std::unique_ptr<std::vector<std::thread::id>> threadIds =
+      std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  std::chrono::system_clock::time_point timeNow =
+      std::chrono::system_clock::now();
+  std::chrono::system_clock::time_point timeExecuted;
+
+  // Act
+  submittableExecutor->Schedule(
+      [&]() {
+        timeExecuted = std::chrono::system_clock::now();
+        threadIds->push_back(std::this_thread::get_id());
+        output.append(RUNNABLE_0_TEXT.c_str());
+        notification.Notify();
+      },
+      absl::Milliseconds(50));
+
+  ASSERT_TRUE(
+      notification.WaitForNotificationWithTimeout(absl::Milliseconds(200)));
+  submittableExecutor->Shutdown();
+
+  ASSERT_EQ(threadIds->size(), 2);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  ASSERT_EQ(output, expected);
+}
+
+TEST(ScheduledExecutorTests, CancelSucceeds) {
+  absl::Notification notification;
+  // Arrange
+  std::string expected("");
+
+  auto submittableExecutor = std::make_unique<ScheduledExecutor>();
+  std::string output = std::string();
+  // Container to note threads that ran
+  std::unique_ptr<std::vector<std::thread::id>> threadIds =
+      std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  // Act
+  auto cancelable = submittableExecutor->Schedule(
+      [&]() {
+        threadIds->push_back(std::this_thread::get_id());
+        output.append(RUNNABLE_0_TEXT.c_str());
+        notification.Notify();
+      },
+      absl::Milliseconds(1000));
+
+  auto actual = cancelable->Cancel();
+
+  EXPECT_FALSE(
+      notification.WaitForNotificationWithTimeout(absl::Milliseconds(2000)));
+  submittableExecutor->Shutdown();
+
+  // Assert
+  ASSERT_TRUE(actual);
+  ASSERT_EQ(threadIds->size(), 1);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  ASSERT_EQ(output, expected);
+}
+
+TEST(ScheduledExecutorTests, CancelAfterStartedFails) {
+  absl::Notification notification;
+  // Arrange
+  std::string expected(RUNNABLE_0_TEXT.c_str());
+
+  auto submittableExecutor = std::make_unique<ScheduledExecutor>();
+  std::string output = std::string();
+  // Container to note threads that ran
+  std::unique_ptr<std::vector<std::thread::id>> threadIds =
+      std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  // Act
+  auto cancelable = submittableExecutor->Schedule(
+      [&]() {
+        threadIds->push_back(std::this_thread::get_id());
+        output.append(RUNNABLE_0_TEXT.c_str());
+        notification.Notify();
+      },
+      absl::Milliseconds(100));
+
+  absl::SleepFor(absl::Milliseconds(200));
+  auto actual = cancelable->Cancel();
+
+  ASSERT_TRUE(
+      notification.WaitForNotificationWithTimeout(absl::Milliseconds(2000)));
+  submittableExecutor->Shutdown();
+
+  // Assert
+  ASSERT_FALSE(actual);
+  ASSERT_EQ(threadIds->size(), 2);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  ASSERT_EQ(output, expected);
+}
+
+}  // namespace
+}  // namespace linux
+}  // namespace nearby

internal/platform/implementation/linux/submittable_executor.cc

@@ -0,0 +1,63 @@
+// Copyright 2021 Google LLC
+//
+// 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
+//
+//     https://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 "internal/platform/implementation/linux/submittable_executor.h"
+
+#include "internal/platform/implementation/linux/executor.h"
+#include "internal/platform/logging.h"
+
+namespace nearby {
+namespace linux {
+
+SubmittableExecutor::SubmittableExecutor() : SubmittableExecutor(1) {}
+
+SubmittableExecutor::SubmittableExecutor(int32_t max_concurrancy)
+    : executor_(std::make_unique<nearby::linux::Executor>(max_concurrancy)),
+      shut_down_(false) {}
+
+bool SubmittableExecutor::DoSubmit(Runnable&& wrapped_callable) {
+  if (!shut_down_) {
+    executor_->Execute(std::move(wrapped_callable));
+    return true;
+  }
+
+  NEARBY_LOGS(ERROR) << "Error: " << __func__
+                     << ": Attempt to DoSubmit on a shutdown executor.";
+
+  return false;
+}
+
+// https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/Executor.html#execute-java.lang.Runnable-
+void SubmittableExecutor::Execute(Runnable&& runnable) {
+  if (!shut_down_) {
+    executor_->Execute(std::move(runnable));
+  } else {
+    NEARBY_LOGS(ERROR) << "Error: " << __func__
+                       << ": Attempt to Execute on a shutdown executor.";
+  }
+}
+
+// https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html#shutdown--
+void SubmittableExecutor::Shutdown() {
+  if (!shut_down_) {
+    executor_->Shutdown();
+    shut_down_ = true;
+  }
+
+  NEARBY_LOGS(ERROR) << "Error: " << __func__
+                     << ": Attempt to Shutdown on a shutdown executor.";
+}
+
+}  // namespace linux
+}  // namespace nearby

internal/platform/implementation/linux/submittable_executor.h

@@ -0,0 +1,53 @@
+// Copyright 2020 Google LLC
+//
+// 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
+//
+//     https://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.
+
+#ifndef PLATFORM_IMPL_LINUX_SUBMITTABLE_EXECUTOR_H_
+#define PLATFORM_IMPL_LINUX_SUBMITTABLE_EXECUTOR_H_
+
+#include "internal/platform/implementation/submittable_executor.h"
+#include "internal/platform/implementation/linux/executor.h"
+
+namespace nearby {
+namespace linux {
+
+// Main interface to be used by platform as a base class for
+// - MultiThreadExecutorWrapper
+// - SingleThreadExecutorWrapper
+// Platform must override bool submit(absl::AnyInvocable<void()>) method.
+class SubmittableExecutor : public api::SubmittableExecutor {
+ public:
+  SubmittableExecutor();
+  SubmittableExecutor(int32_t maxConcurrancy);
+  ~SubmittableExecutor() override = default;
+
+  // Submit a callable (with no delay).
+  // Returns true, if callable was submitted, false otherwise.
+  // Callable is not submitted if shutdown is in progress.
+  bool DoSubmit(Runnable&& wrapped_callable) override;
+
+  // https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/Executor.html#execute-java.lang.Runnable-
+  void Execute(Runnable&& runnable) override;
+
+  // https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html#shutdown--
+  void Shutdown() override;
+
+ private:
+  std::unique_ptr<nearby::linux::Executor> executor_;
+  std::atomic_bool shut_down_ = false;
+};
+
+}  // namespace linux
+}  // namespace nearby
+
+#endif  // PLATFORM_IMPL_LINUX_SUBMITTABLE_EXECUTOR_H_

internal/platform/implementation/linux/submittable_executor_test.cc

@@ -0,0 +1,250 @@
+// Copyright 2021 Google LLC
+//
+// 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
+//
+//     https://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 "internal/platform/implementation/linux/submittable_executor.h"
+
+#include <utility>
+#include <thread>
+
+#include "gtest/gtest.h"
+#include "absl/synchronization/blocking_counter.h"
+#include "absl/synchronization/notification.h"
+#include "absl/time/time.h"
+#include "internal/platform/implementation/linux/test_data.h"
+
+namespace nearby {
+namespace linux {
+namespace {
+
+constexpr absl::Duration kWaitTimeout = absl::Milliseconds(200);
+
+TEST(SubmittableExecutorTests, SingleThreadedExecuteSucceeds) {
+  absl::Notification notification;
+  // Arrange
+  std::string expected(RUNNABLE_0_TEXT.c_str());
+
+  auto submittableExecutor = std::make_unique<SubmittableExecutor>();
+  std::string output = std::string();
+  // Container to note threads that ran
+  auto threadIds = std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  // Act
+  submittableExecutor->Execute([&]() {
+    threadIds->push_back(std::this_thread::get_id());
+    output.append(RUNNABLE_0_TEXT.c_str());
+    notification.Notify();
+  });
+
+  ASSERT_TRUE(notification.WaitForNotificationWithTimeout(kWaitTimeout));
+  submittableExecutor->Shutdown();
+
+  //  Assert
+  //  We should've run 1 time on the main thread, and 1 times on the
+  //  workerThread
+  ASSERT_EQ(threadIds->size(), 2);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  ASSERT_EQ(output, expected);
+}
+
+TEST(SubmittableExecutorTests, SingleThreadedExecuteAfterShutdownFails) {
+  // Arrange
+  std::string expected("");
+
+  auto submittableExecutor = std::make_unique<SubmittableExecutor>();
+  std::string output = std::string();
+  // Container to note threads that ran
+  auto threadIds = std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  submittableExecutor->Shutdown();
+
+  // Act
+  submittableExecutor->Execute([&output, &threadIds]() {
+    threadIds->push_back(std::this_thread::get_id());
+    output.append(RUNNABLE_0_TEXT.c_str());
+  });
+
+  //  Assert
+  //  We should've run 1 time on the main thread, and 0 times on the
+  //  workerThread
+  ASSERT_EQ(threadIds->size(), 1);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  ASSERT_EQ(output, expected);
+}
+
+TEST(SubmittableExecutorTests, SingleThreadedDoSubmitSucceeds) {
+  absl::Notification notification;
+  // Arrange
+  std::string expected(RUNNABLE_0_TEXT.c_str());
+
+  auto submittableExecutor = std::make_unique<SubmittableExecutor>();
+  std::string output = std::string();
+  // Container to note threads that ran
+  auto threadIds = std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  // Act
+  auto result = submittableExecutor->DoSubmit([&]() {
+    threadIds->push_back(std::this_thread::get_id());
+    output.append(RUNNABLE_0_TEXT.c_str());
+    notification.Notify();
+  });
+
+  ASSERT_TRUE(notification.WaitForNotificationWithTimeout(kWaitTimeout));
+  submittableExecutor->Shutdown();
+
+  //  Assert
+  //  We should've said we were going to run this one
+  ASSERT_TRUE(result);
+  //  We should've run 1 time on the main thread, and 1 times on the
+  //  workerThread
+  ASSERT_EQ(threadIds->size(), 2);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  ASSERT_EQ(output, expected);
+}
+
+TEST(SubmittableExecutorTests,
+     SingleThreadedDoSubmitAfterShutdownReturnsFalse) {
+  // Arrange
+  std::string expected("");
+
+  auto submittableExecutor = std::make_unique<SubmittableExecutor>();
+  std::unique_ptr<std::string> output = std::make_unique<std::string>();
+  // Container to note threads that ran
+  auto threadIds = std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  submittableExecutor->Shutdown();
+
+  // Act
+  auto result = submittableExecutor->DoSubmit([&output, &threadIds]() {
+    threadIds->push_back(std::this_thread::get_id());
+    output->append(RUNNABLE_0_TEXT.c_str());
+  });
+
+  //  Assert
+  //  We should've said we were going to run this one
+  ASSERT_FALSE(result);
+  //  We should've run 1 time on the main thread, and 1 times on the
+  //  workerThread
+  ASSERT_EQ(threadIds->size(), 1);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  ASSERT_EQ(*output.get(), expected);
+}
+
+TEST(SubmittableExecutorTests, SingleThreadedExecuteMultipleTasksSucceeds) {
+  absl::BlockingCounter blocking_counter(5);
+
+  // Arrange
+  std::string expected(RUNNABLE_ALL_TEXT.c_str());
+
+  auto submittableExecutor = std::make_unique<SubmittableExecutor>();
+  std::unique_ptr<std::string> output = std::make_unique<std::string>();
+  // Container to note threads that ran
+  auto threadIds = std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  // Act
+  for (int index = 0; index < 5; index++) {
+    submittableExecutor->Execute([&, index]() {
+      threadIds->push_back(std::this_thread::get_id());
+      char buffer[128];
+      snprintf(buffer, sizeof(buffer), "%s%d, ", RUNNABLE_TEXT.c_str(), index);
+      output->append(std::string(buffer));
+      blocking_counter.DecrementCount();
+    });
+  }
+
+  blocking_counter.Wait();
+  submittableExecutor->Shutdown();
+
+  //  Assert
+  //  We should've run 1 time on the main thread, and 5 times on the
+  //  workerThread
+  ASSERT_EQ(threadIds->size(), 6);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  auto workerThreadId = threadIds->at(1);
+  for (int index = 1; index < threadIds->size(); index++) {
+    ASSERT_EQ(threadIds->at(index), workerThreadId);
+  }
+
+  //  We should of run them in the order submitted
+  ASSERT_EQ(*output.get(), expected);
+}
+
+TEST(SubmittableExecutorTests, SingleThreadedDoSubmitMultipleTasksSucceeds) {
+  absl::BlockingCounter blocking_counter(5);
+
+  // Arrange
+  std::string expected(RUNNABLE_ALL_TEXT.c_str());
+
+  auto submittableExecutor = std::make_unique<SubmittableExecutor>();
+  std::unique_ptr<std::string> output = std::make_unique<std::string>();
+  // Container to note threads that ran
+  auto threadIds = std::make_unique<std::vector<std::thread::id>>();
+
+  threadIds->push_back(std::this_thread::get_id());
+
+  // Act
+  bool result = true;
+  for (int index = 0; index < 5; index++) {
+    result &= submittableExecutor->DoSubmit([&, index]() {
+      threadIds->push_back(std::this_thread::get_id());
+      char buffer[128];
+      snprintf(buffer, sizeof(buffer), "%s%d, ", RUNNABLE_TEXT.c_str(), index);
+      output->append(std::string(buffer));
+      blocking_counter.DecrementCount();
+    });
+  }
+
+  blocking_counter.Wait();
+  submittableExecutor->Shutdown();
+
+  //  Assert
+  //  All of these should have submitted
+  ASSERT_TRUE(result);
+  //  We should've run 1 time on the main thread, and 5 times on the
+  //  workerThread
+  ASSERT_EQ(threadIds->size(), 6);
+  //  We should still be on the main thread
+  ASSERT_EQ(std::this_thread::get_id(), threadIds->at(0));
+  //  We should've run all runnables on the worker thread
+  auto workerThreadId = threadIds->at(1);
+  for (int index = 1; index < threadIds->size(); index++) {
+    ASSERT_EQ(threadIds->at(index), workerThreadId);
+  }
+
+  //  We should of run them in the order submitted
+  ASSERT_EQ(*output.get(), expected);
+}
+
+}  // namespace
+}  // namespace linux
+}  // namespace nearby

internal/platform/implementation/linux/thread_pool_test.cc

@@ -0,0 +1,71 @@
+// Copyright 2022 Google LLC
+//
+// 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
+//
+//     https://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 "internal/platform/implementation/linux/thread_pool.h"
+
+#include <vector>
+
+#include "gtest/gtest.h"
+#include "absl/synchronization/blocking_counter.h"
+#include "absl/synchronization/notification.h"
+#include "absl/time/clock.h"
+#include "absl/time/time.h"
+
+namespace nearby {
+namespace linux {
+namespace {
+
+constexpr int kTaskCount = 10;
+
+TEST(ThreadPool, TasksInSingleThreadRunInSequence) {
+  absl::BlockingCounter blocking_counter(kTaskCount);
+  auto pool = ThreadPool::Create(1);
+  std::vector<int> completed_tasks;
+  std::vector<int> expected_tasks;
+
+  for (int i = 0; i < kTaskCount; ++i) {
+    expected_tasks.push_back(i);
+    pool->Run([&, i]() {
+      absl::SleepFor(absl::Milliseconds(200));
+      completed_tasks.push_back(i);
+      blocking_counter.DecrementCount();
+    });
+  }
+
+  blocking_counter.Wait();
+  EXPECT_EQ(completed_tasks, expected_tasks);
+  pool->ShutDown();
+}
+
+TEST(ThreadPool, TasksInMultipleThreadsRunInParallel) {
+  absl::BlockingCounter blocking_counter(kTaskCount);
+  absl::Time start_time = absl::Now();
+
+  auto pool = ThreadPool::Create(2);
+
+  for (int i = 0; i < kTaskCount; ++i) {
+    pool->Run([&]() {
+      absl::SleepFor(absl::Milliseconds(200));
+      blocking_counter.DecrementCount();
+    });
+  }
+
+  blocking_counter.Wait();
+  EXPECT_TRUE(absl::Now() - start_time < absl::Milliseconds(1500));
+  pool->ShutDown();
+}
+
+}  // namespace
+}  // namespace linux
+}  // namespace nearby