[wpinet] Move network portions of wpiutil into new wpinet library (#4077)

wpinet/src/test/native/cpp/uv/UvAsyncFunctionTest.cpp

@@ -0,0 +1,264 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include "wpinet/uv/AsyncFunction.h"  // NOLINT(build/include_order)
+
+#include "gtest/gtest.h"  // NOLINT(build/include_order)
+
+#include <thread>
+
+#include "wpinet/uv/Loop.h"
+#include "wpinet/uv/Prepare.h"
+
+namespace wpi::uv {
+
+TEST(UvAsyncFunctionTest, Basic) {
+  int prepare_cb_called = 0;
+  int async_cb_called[2] = {0, 0};
+  int close_cb_called = 0;
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async = AsyncFunction<int(int)>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  loop->error.connect([](Error) { FAIL(); });
+
+  prepare->error.connect([](Error) { FAIL(); });
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] {
+      auto call0 = async->Call(0);
+      auto call1 = async->Call(1);
+      ASSERT_EQ(call0.get(), 1);
+      ASSERT_EQ(call1.get(), 2);
+    });
+  });
+  prepare->Start();
+
+  async->error.connect([](Error) { FAIL(); });
+  async->closed.connect([&] { close_cb_called++; });
+  async->wakeup = [&](promise<int> out, int v) {
+    ++async_cb_called[v];
+    if (v == 1) {
+      async->Close();
+      prepare->Close();
+    }
+    out.set_value(v + 1);
+  };
+
+  loop->Run();
+
+  ASSERT_EQ(async_cb_called[0], 1);
+  ASSERT_EQ(async_cb_called[1], 1);
+  ASSERT_EQ(close_cb_called, 1);
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+TEST(UvAsyncFunctionTest, Ref) {
+  int prepare_cb_called = 0;
+  int val = 0;
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async = AsyncFunction<int(int, int&)>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] { ASSERT_EQ(async->Call(1, val).get(), 2); });
+  });
+  prepare->Start();
+
+  async->wakeup = [&](promise<int> out, int v, int& r) {
+    r = v;
+    async->Close();
+    prepare->Close();
+    out.set_value(v + 1);
+  };
+
+  loop->Run();
+
+  ASSERT_EQ(val, 1);
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+TEST(UvAsyncFunctionTest, Movable) {
+  int prepare_cb_called = 0;
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async =
+      AsyncFunction<std::unique_ptr<int>(std::unique_ptr<int>)>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] {
+      auto val = std::make_unique<int>(1);
+      auto val2 = async->Call(std::move(val)).get();
+      ASSERT_NE(val2, nullptr);
+      ASSERT_EQ(*val2, 1);
+    });
+  });
+  prepare->Start();
+
+  async->wakeup = [&](promise<std::unique_ptr<int>> out,
+                      std::unique_ptr<int> v) {
+    async->Close();
+    prepare->Close();
+    out.set_value(std::move(v));
+  };
+
+  loop->Run();
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+TEST(UvAsyncFunctionTest, CallIgnoreResult) {
+  int prepare_cb_called = 0;
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async =
+      AsyncFunction<std::unique_ptr<int>(std::unique_ptr<int>)>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] { async->Call(std::make_unique<int>(1)); });
+  });
+  prepare->Start();
+
+  async->wakeup = [&](promise<std::unique_ptr<int>> out,
+                      std::unique_ptr<int> v) {
+    async->Close();
+    prepare->Close();
+    out.set_value(std::move(v));
+  };
+
+  loop->Run();
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+TEST(UvAsyncFunctionTest, VoidCall) {
+  int prepare_cb_called = 0;
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async = AsyncFunction<void()>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] { async->Call(); });
+  });
+  prepare->Start();
+
+  async->wakeup = [&](promise<void> out) {
+    async->Close();
+    prepare->Close();
+    out.set_value();
+  };
+
+  loop->Run();
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+TEST(UvAsyncFunctionTest, WaitFor) {
+  int prepare_cb_called = 0;
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async = AsyncFunction<int()>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] {
+      ASSERT_FALSE(async->Call().wait_for(std::chrono::milliseconds(10)));
+    });
+  });
+  prepare->Start();
+
+  async->wakeup = [&](promise<int> out) {
+    async->Close();
+    prepare->Close();
+    std::this_thread::sleep_for(std::chrono::milliseconds(100));
+    out.set_value(1);
+  };
+
+  loop->Run();
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+TEST(UvAsyncFunctionTest, VoidWaitFor) {
+  int prepare_cb_called = 0;
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async = AsyncFunction<void()>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] {
+      ASSERT_FALSE(async->Call().wait_for(std::chrono::milliseconds(10)));
+    });
+  });
+  prepare->Start();
+
+  async->wakeup = [&](promise<void> out) {
+    async->Close();
+    prepare->Close();
+    std::this_thread::sleep_for(std::chrono::milliseconds(100));
+    out.set_value();
+  };
+
+  loop->Run();
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+}  // namespace wpi::uv

wpinet/src/test/native/cpp/uv/UvAsyncTest.cpp

@@ -0,0 +1,186 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "wpinet/uv/Async.h"  // NOLINT(build/include_order)
+
+#include "gtest/gtest.h"  // NOLINT(build/include_order)
+
+#include <atomic>
+#include <thread>
+
+#include <wpi/mutex.h>
+
+#include "wpinet/uv/Loop.h"
+#include "wpinet/uv/Prepare.h"
+
+namespace wpi::uv {
+
+TEST(UvAsyncTest, CallbackOnly) {
+  std::atomic_int async_cb_called{0};
+  int prepare_cb_called = 0;
+  int close_cb_called = 0;
+
+  wpi::mutex mutex;
+  mutex.lock();
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async = Async<>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  loop->error.connect([](Error) { FAIL(); });
+
+  prepare->error.connect([](Error) { FAIL(); });
+  prepare->closed.connect([&] { close_cb_called++; });
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] {
+      for (;;) {
+        mutex.lock();
+        int n = async_cb_called;
+        mutex.unlock();
+
+        if (n == 3) {
+          break;
+        }
+
+        async->Send();
+
+        std::this_thread::yield();
+      }
+    });
+    mutex.unlock();
+  });
+  prepare->Start();
+
+  async->error.connect([](Error) { FAIL(); });
+  async->closed.connect([&] { close_cb_called++; });
+  async->wakeup.connect([&] {
+    mutex.lock();
+    int n = ++async_cb_called;
+    mutex.unlock();
+
+    if (n == 3) {
+      async->Close();
+      prepare->Close();
+    }
+  });
+
+  loop->Run();
+
+  ASSERT_GT(prepare_cb_called, 0);
+  ASSERT_EQ(async_cb_called, 3);
+  ASSERT_EQ(close_cb_called, 2);
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+TEST(UvAsyncTest, Data) {
+  int prepare_cb_called = 0;
+  int async_cb_called[2] = {0, 0};
+  int close_cb_called = 0;
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async = Async<int, std::function<void(int)>>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  loop->error.connect([](Error) { FAIL(); });
+
+  prepare->error.connect([](Error) { FAIL(); });
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] {
+      async->Send(0, [&](int v) {
+        ASSERT_EQ(v, 0);
+        ++async_cb_called[0];
+      });
+      async->Send(1, [&](int v) {
+        ASSERT_EQ(v, 1);
+        ++async_cb_called[1];
+        async->Close();
+        prepare->Close();
+      });
+    });
+  });
+  prepare->Start();
+
+  async->error.connect([](Error) { FAIL(); });
+  async->closed.connect([&] { close_cb_called++; });
+  async->wakeup.connect([&](int v, std::function<void(int)> f) { f(v); });
+
+  loop->Run();
+
+  ASSERT_EQ(async_cb_called[0], 1);
+  ASSERT_EQ(async_cb_called[1], 1);
+  ASSERT_EQ(close_cb_called, 1);
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+TEST(UvAsyncTest, DataRef) {
+  int prepare_cb_called = 0;
+  int val = 0;
+
+  std::thread theThread;
+
+  auto loop = Loop::Create();
+  auto async = Async<int, int&>::Create(loop);
+  auto prepare = Prepare::Create(loop);
+
+  prepare->prepare.connect([&] {
+    if (prepare_cb_called++) {
+      return;
+    }
+    theThread = std::thread([&] { async->Send(1, val); });
+  });
+  prepare->Start();
+
+  async->wakeup.connect([&](int v, int& r) {
+    r = v;
+    async->Close();
+    prepare->Close();
+  });
+
+  loop->Run();
+
+  ASSERT_EQ(val, 1);
+
+  if (theThread.joinable()) {
+    theThread.join();
+  }
+}
+
+}  // namespace wpi::uv

wpinet/src/test/native/cpp/uv/UvBufferTest.cpp

@@ -0,0 +1,48 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include "wpinet/uv/Buffer.h"  // NOLINT(build/include_order)
+
+#include "gtest/gtest.h"  // NOLINT(build/include_order)
+
+namespace wpi::uv {
+
+TEST(UvSimpleBufferPoolTest, ConstructDefault) {
+  SimpleBufferPool<> pool;
+  auto buf1 = pool.Allocate();
+  ASSERT_EQ(buf1.len, 4096u);  // NOLINT
+  pool.Release({&buf1, 1});
+}
+
+TEST(UvSimpleBufferPoolTest, ConstructSize) {
+  SimpleBufferPool<4> pool{8192};
+  auto buf1 = pool.Allocate();
+  ASSERT_EQ(buf1.len, 8192u);  // NOLINT
+  pool.Release({&buf1, 1});
+}
+
+TEST(UvSimpleBufferPoolTest, ReleaseReuse) {
+  SimpleBufferPool<4> pool;
+  auto buf1 = pool.Allocate();
+  auto buf1copy = buf1;
+  auto origSize = buf1.len;
+  buf1.len = 8;
+  pool.Release({&buf1, 1});
+  ASSERT_EQ(buf1.base, nullptr);
+  auto buf2 = pool.Allocate();
+  ASSERT_EQ(buf1copy.base, buf2.base);
+  ASSERT_EQ(buf2.len, origSize);
+  pool.Release({&buf2, 1});
+}
+
+TEST(UvSimpleBufferPoolTest, ClearRemaining) {
+  SimpleBufferPool<4> pool;
+  auto buf1 = pool.Allocate();
+  pool.Release({&buf1, 1});
+  ASSERT_EQ(pool.Remaining(), 1u);
+  pool.Clear();
+  ASSERT_EQ(pool.Remaining(), 0u);
+}
+
+}  // namespace wpi::uv

wpinet/src/test/native/cpp/uv/UvGetAddrInfoTest.cpp

@@ -0,0 +1,109 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "wpinet/uv/GetAddrInfo.h"  // NOLINT(build/include_order)
+
+#include "gtest/gtest.h"  // NOLINT(build/include_order)
+
+#include "wpinet/uv/Loop.h"
+
+#define CONCURRENT_COUNT 10
+
+namespace wpi::uv {
+
+TEST(UvGetAddrInfoTest, BothNull) {
+  int fail_cb_called = 0;
+
+  auto loop = Loop::Create();
+  loop->error.connect([&](Error err) {
+    ASSERT_EQ(err.code(), UV_EINVAL);
+    fail_cb_called++;
+  });
+
+  GetAddrInfo(
+      loop, [](const addrinfo&) { FAIL(); }, "");
+  loop->Run();
+  ASSERT_EQ(fail_cb_called, 1);
+}
+
+TEST(UvGetAddrInfoTest, FailedLookup) {
+  int fail_cb_called = 0;
+
+  auto loop = Loop::Create();
+  loop->error.connect([&](Error err) {
+    ASSERT_EQ(fail_cb_called, 0);
+    ASSERT_LT(err.code(), 0);
+    fail_cb_called++;
+  });
+
+  // Use a FQDN by ending in a period
+  GetAddrInfo(
+      loop, [](const addrinfo&) { FAIL(); }, "xyzzy.xyzzy.xyzzy.");
+  loop->Run();
+  ASSERT_EQ(fail_cb_called, 1);
+}
+
+TEST(UvGetAddrInfoTest, Basic) {
+  int getaddrinfo_cbs = 0;
+
+  auto loop = Loop::Create();
+  loop->error.connect([](Error) { FAIL(); });
+
+  GetAddrInfo(
+      loop, [&](const addrinfo&) { getaddrinfo_cbs++; }, "localhost");
+
+  loop->Run();
+
+  ASSERT_EQ(getaddrinfo_cbs, 1);
+}
+
+#ifndef _WIN32
+TEST(UvGetAddrInfoTest, Concurrent) {
+  int getaddrinfo_cbs = 0;
+  int callback_counts[CONCURRENT_COUNT];
+
+  auto loop = Loop::Create();
+  loop->error.connect([](Error) { FAIL(); });
+
+  for (int i = 0; i < CONCURRENT_COUNT; i++) {
+    callback_counts[i] = 0;
+    GetAddrInfo(
+        loop,
+        [i, &callback_counts, &getaddrinfo_cbs](const addrinfo&) {
+          callback_counts[i]++;
+          getaddrinfo_cbs++;
+        },
+        "localhost");
+  }
+
+  loop->Run();
+
+  for (int i = 0; i < CONCURRENT_COUNT; i++) {
+    ASSERT_EQ(callback_counts[i], 1);
+  }
+}
+#endif
+
+}  // namespace wpi::uv

wpinet/src/test/native/cpp/uv/UvGetNameInfoTest.cpp

@@ -0,0 +1,74 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "wpinet/uv/GetNameInfo.h"  // NOLINT(build/include_order)
+
+#include "gtest/gtest.h"  // NOLINT(build/include_order)
+
+#include "wpinet/uv/Loop.h"
+
+namespace wpi::uv {
+
+TEST(UvGetNameInfoTest, BasicIp4) {
+  int getnameinfo_cbs = 0;
+
+  auto loop = Loop::Create();
+  loop->error.connect([](Error) { FAIL(); });
+
+  GetNameInfo4(
+      loop,
+      [&](const char* hostname, const char* service) {
+        ASSERT_NE(hostname, nullptr);
+        ASSERT_NE(service, nullptr);
+        getnameinfo_cbs++;
+      },
+      "127.0.0.1", 80);
+
+  loop->Run();
+
+  ASSERT_EQ(getnameinfo_cbs, 1);
+}
+
+TEST(UvGetNameInfoTest, BasicIp6) {
+  int getnameinfo_cbs = 0;
+
+  auto loop = Loop::Create();
+  loop->error.connect([](Error) { FAIL(); });
+
+  GetNameInfo6(
+      loop,
+      [&](const char* hostname, const char* service) {
+        ASSERT_NE(hostname, nullptr);
+        ASSERT_NE(service, nullptr);
+        getnameinfo_cbs++;
+      },
+      "::1", 80);
+
+  loop->Run();
+
+  ASSERT_EQ(getnameinfo_cbs, 1);
+}
+
+}  // namespace wpi::uv

wpinet/src/test/native/cpp/uv/UvLoopWalkTest.cpp

@@ -0,0 +1,69 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "wpinet/uv/Loop.h"  // NOLINT(build/include_order)
+
+#include "gtest/gtest.h"  // NOLINT(build/include_order)
+
+#include "wpinet/uv/Timer.h"
+
+namespace wpi::uv {
+
+TEST(UvLoopTest, Walk) {
+  int seen_timer_handle = 0;
+
+  auto loop = Loop::Create();
+  auto timer = Timer::Create(loop);
+
+  loop->error.connect([](Error) { FAIL(); });
+
+  timer->error.connect([](Error) { FAIL(); });
+
+  timer->timeout.connect([&, theTimer = timer.get()] {
+    theTimer->GetLoopRef().Walk([&](Handle& it) {
+      if (&it == timer.get()) {
+        seen_timer_handle++;
+      }
+    });
+    theTimer->Close();
+  });
+  timer->Start(Timer::Time{1});
+
+  // Start event loop, expect to see the timer handle
+  ASSERT_EQ(seen_timer_handle, 0);
+  loop->Run();
+  ASSERT_EQ(seen_timer_handle, 1);
+
+  // Loop is finished, should not see our timer handle
+  seen_timer_handle = 0;
+  loop->Walk([&](Handle& it) {
+    if (&it == timer.get()) {
+      seen_timer_handle++;
+    }
+  });
+  ASSERT_EQ(seen_timer_handle, 0);
+}
+
+}  // namespace wpi::uv

wpinet/src/test/native/cpp/uv/UvTimerTest.cpp

@@ -0,0 +1,69 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include "wpinet/uv/Timer.h"  // NOLINT(build/include_order)
+
+#include "gtest/gtest.h"
+
+namespace wpi::uv {
+
+TEST(UvTimerTest, StartAndStop) {
+  auto loop = Loop::Create();
+  auto handleNoRepeat = Timer::Create(loop);
+  auto handleRepeat = Timer::Create(loop);
+
+  bool checkTimerNoRepeatEvent = false;
+  bool checkTimerRepeatEvent = false;
+
+  handleNoRepeat->error.connect([](Error) { FAIL(); });
+  handleRepeat->error.connect([](Error) { FAIL(); });
+
+  handleNoRepeat->timeout.connect(
+      [&checkTimerNoRepeatEvent, handle = handleNoRepeat.get()] {
+        ASSERT_FALSE(checkTimerNoRepeatEvent);
+        checkTimerNoRepeatEvent = true;
+        handle->Stop();
+        handle->Close();
+        ASSERT_TRUE(handle->IsClosing());
+      });
+
+  handleRepeat->timeout.connect(
+      [&checkTimerRepeatEvent, handle = handleRepeat.get()] {
+        if (checkTimerRepeatEvent) {
+          handle->Stop();
+          handle->Close();
+          ASSERT_TRUE(handle->IsClosing());
+        } else {
+          checkTimerRepeatEvent = true;
+          ASSERT_FALSE(handle->IsClosing());
+        }
+      });
+
+  handleNoRepeat->Start(Timer::Time{0}, Timer::Time{0});
+  handleRepeat->Start(Timer::Time{0}, Timer::Time{1});
+
+  ASSERT_TRUE(handleNoRepeat->IsActive());
+  ASSERT_FALSE(handleNoRepeat->IsClosing());
+
+  ASSERT_TRUE(handleRepeat->IsActive());
+  ASSERT_FALSE(handleRepeat->IsClosing());
+
+  loop->Run();
+
+  ASSERT_TRUE(checkTimerNoRepeatEvent);
+  ASSERT_TRUE(checkTimerRepeatEvent);
+}
+
+TEST(UvTimerTest, Repeat) {
+  auto loop = Loop::Create();
+  auto handle = Timer::Create(loop);
+
+  handle->SetRepeat(Timer::Time{42});
+  ASSERT_EQ(handle->GetRepeat(), Timer::Time{42});
+  handle->Close();
+
+  loop->Run();  // forces close callback to run
+}
+
+}  // namespace wpi::uv