pw_async2/pend_func_task_test.cc

// Copyright 2023 The Pigweed Authors
//
// 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 "pw_async2/pend_func_task.h"

#include "pw_async2/dispatcher.h"
#include "pw_unit_test/framework.h"

namespace {

using ::pw::async2::Context;
using ::pw::async2::Dispatcher;
using ::pw::async2::PendFuncTask;
using ::pw::async2::Pending;
using ::pw::async2::Poll;
using ::pw::async2::Ready;
using ::pw::async2::WaitReason;
using ::pw::async2::Waker;

TEST(PendFuncTask, PendDelegatesToFunc) {
  Dispatcher dispatcher;

  Waker waker;
  int poll_count = 0;
  bool allow_completion = false;

  PendFuncTask func_task([&](Context& cx) -> Poll<> {
    ++poll_count;
    if (allow_completion) {
      return Ready();
    }
    waker = cx.GetWaker(WaitReason::Unspecified());
    return Pending();
  });

  dispatcher.Post(func_task);

  EXPECT_EQ(poll_count, 0);
  EXPECT_EQ(dispatcher.RunUntilStalled(), Pending());
  EXPECT_EQ(poll_count, 1);

  // Unwoken task is not polled.
  EXPECT_EQ(dispatcher.RunUntilStalled(), Pending());
  EXPECT_EQ(poll_count, 1);

  std::move(waker).Wake();
  allow_completion = true;
  EXPECT_EQ(dispatcher.RunUntilStalled(), Ready());
  EXPECT_EQ(poll_count, 2);
}

}  // namespace