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task_environment.cc
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task_environment.cc
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// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/test/task_environment.h"
#include <algorithm>
#include <memory>
#include "base/bind_helpers.h"
#include "base/lazy_instance.h"
#include "base/location.h"
#include "base/logging.h"
#include "base/memory/ptr_util.h"
#include "base/message_loop/message_pump.h"
#include "base/message_loop/message_pump_type.h"
#include "base/no_destructor.h"
#include "base/run_loop.h"
#include "base/synchronization/condition_variable.h"
#include "base/synchronization/lock.h"
#include "base/task/post_task.h"
#include "base/task/sequence_manager/sequence_manager_impl.h"
#include "base/task/sequence_manager/time_domain.h"
#include "base/task/simple_task_executor.h"
#include "base/task/thread_pool/thread_pool_impl.h"
#include "base/task/thread_pool/thread_pool_instance.h"
#include "base/test/bind_test_util.h"
#include "base/test/test_mock_time_task_runner.h"
#include "base/test/test_timeouts.h"
#include "base/thread_annotations.h"
#include "base/threading/sequence_local_storage_map.h"
#include "base/threading/thread_local.h"
#include "base/threading/thread_restrictions.h"
#include "base/threading/thread_task_runner_handle.h"
#include "base/time/clock.h"
#include "base/time/tick_clock.h"
#include "base/time/time.h"
#include "base/time/time_override.h"
#include "testing/gtest/include/gtest/gtest.h"
#if defined(OS_POSIX) || defined(OS_FUCHSIA)
#include "base/files/file_descriptor_watcher_posix.h"
#endif
namespace base {
namespace test {
namespace {
ObserverList<TaskEnvironment::DestructionObserver>& GetDestructionObservers() {
static NoDestructor<ObserverList<TaskEnvironment::DestructionObserver>>
instance;
return *instance;
}
base::MessagePumpType GetMessagePumpTypeForMainThreadType(
TaskEnvironment::MainThreadType main_thread_type) {
switch (main_thread_type) {
case TaskEnvironment::MainThreadType::DEFAULT:
return MessagePumpType::DEFAULT;
case TaskEnvironment::MainThreadType::UI:
return MessagePumpType::UI;
case TaskEnvironment::MainThreadType::IO:
return MessagePumpType::IO;
}
NOTREACHED();
return MessagePumpType::DEFAULT;
}
std::unique_ptr<sequence_manager::SequenceManager>
CreateSequenceManagerForMainThreadType(
TaskEnvironment::MainThreadType main_thread_type) {
auto type = GetMessagePumpTypeForMainThreadType(main_thread_type);
return sequence_manager::CreateSequenceManagerOnCurrentThreadWithPump(
MessagePump::Create(type),
base::sequence_manager::SequenceManager::Settings::Builder()
.SetMessagePumpType(type)
.Build());
}
class TickClockBasedClock : public Clock {
public:
explicit TickClockBasedClock(const TickClock* tick_clock)
: tick_clock_(*tick_clock),
start_ticks_(tick_clock_.NowTicks()),
start_time_(Time::UnixEpoch()) {}
Time Now() const override {
return start_time_ + (tick_clock_.NowTicks() - start_ticks_);
}
private:
const TickClock& tick_clock_;
const TimeTicks start_ticks_;
const Time start_time_;
};
} // namespace
class TaskEnvironment::TestTaskTracker
: public internal::ThreadPoolImpl::TaskTrackerImpl {
public:
TestTaskTracker();
// Allow running tasks. Returns whether tasks were previously allowed to run.
bool AllowRunTasks();
// Disallow running tasks. Returns true on success; success requires there to
// be no tasks currently running. Returns false if >0 tasks are currently
// running. Prior to returning false, it will attempt to block until at least
// one task has completed (in an attempt to avoid callers busy-looping
// DisallowRunTasks() calls with the same set of slowly ongoing tasks). This
// block attempt will also have a short timeout (in an attempt to prevent the
// fallout of blocking: if the only task remaining is blocked on the main
// thread, waiting for it to complete results in a deadlock...).
bool DisallowRunTasks();
// Returns true if tasks are currently allowed to run.
bool TasksAllowedToRun() const;
private:
friend class TaskEnvironment;
// internal::ThreadPoolImpl::TaskTrackerImpl:
void RunTask(internal::Task task,
internal::TaskSource* sequence,
const TaskTraits& traits) override;
// Synchronizes accesses to members below.
mutable Lock lock_;
// True if running tasks is allowed.
bool can_run_tasks_ GUARDED_BY(lock_) = true;
// Signaled when |can_run_tasks_| becomes true.
ConditionVariable can_run_tasks_cv_ GUARDED_BY(lock_);
// Signaled when a task is completed.
ConditionVariable task_completed_cv_ GUARDED_BY(lock_);
// Number of tasks that are currently running.
int num_tasks_running_ GUARDED_BY(lock_) = 0;
DISALLOW_COPY_AND_ASSIGN(TestTaskTracker);
};
class TaskEnvironment::MockTimeDomain : public sequence_manager::TimeDomain,
public TickClock {
public:
explicit MockTimeDomain(sequence_manager::SequenceManager* sequence_manager)
: sequence_manager_(sequence_manager) {
DCHECK_EQ(nullptr, current_mock_time_domain_);
current_mock_time_domain_ = this;
}
~MockTimeDomain() override {
DCHECK_EQ(this, current_mock_time_domain_);
current_mock_time_domain_ = nullptr;
}
static MockTimeDomain* current_mock_time_domain_;
static Time GetTime() {
return Time::UnixEpoch() + (current_mock_time_domain_->Now() - TimeTicks());
}
static TimeTicks GetTimeTicks() { return current_mock_time_domain_->Now(); }
using TimeDomain::NextScheduledRunTime;
Optional<TimeTicks> NextScheduledRunTime() const {
// The TimeDomain doesn't know about immediate tasks, check if we have any.
if (!sequence_manager_->IsIdleForTesting())
return Now();
return TimeDomain::NextScheduledRunTime();
}
void AdvanceClock(TimeDelta delta) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
{
AutoLock lock(now_ticks_lock_);
now_ticks_ += delta;
}
if (thread_pool_)
thread_pool_->ProcessRipeDelayedTasksForTesting();
}
static std::unique_ptr<TaskEnvironment::MockTimeDomain> CreateAndRegister(
sequence_manager::SequenceManager* sequence_manager) {
auto mock_time_domain =
std::make_unique<TaskEnvironment::MockTimeDomain>(sequence_manager);
sequence_manager->RegisterTimeDomain(mock_time_domain.get());
return mock_time_domain;
}
void SetThreadPool(internal::ThreadPoolImpl* thread_pool,
const TestTaskTracker* thread_pool_task_tracker) {
DCHECK(!thread_pool_);
DCHECK(!thread_pool_task_tracker_);
thread_pool_ = thread_pool;
thread_pool_task_tracker_ = thread_pool_task_tracker;
}
// sequence_manager::TimeDomain:
sequence_manager::LazyNow CreateLazyNow() const override {
AutoLock lock(now_ticks_lock_);
return sequence_manager::LazyNow(now_ticks_);
}
TimeTicks Now() const override {
// This can be called from any thread.
AutoLock lock(now_ticks_lock_);
return now_ticks_;
}
Optional<TimeDelta> DelayTillNextTask(
sequence_manager::LazyNow* lazy_now) override {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
// Make sure TimeDomain::NextScheduledRunTime has taken canceled tasks into
// account, ReclaimMemory sweeps canceled delayed tasks.
sequence_manager()->ReclaimMemory();
Optional<TimeTicks> run_time = NextScheduledRunTime();
// Check if we've run out of tasks.
if (!run_time)
return base::nullopt;
// Check if we have a task that should be running now. Reading |now_ticks_|
// from the main thread doesn't require the lock.
if (run_time <= TS_UNCHECKED_READ(now_ticks_))
return base::TimeDelta();
// The next task is a future delayed task. Since we're using mock time, we
// don't want an actual OS level delayed wake up scheduled, so pretend we
// have no more work. This will result in appearing idle, TaskEnvironment
// will decide what to do based on that (return to caller or fast-forward
// time).
return base::nullopt;
}
// This method is called when the underlying message pump has run out of
// non-delayed work. Advances time to the next task unless
// |quit_when_idle_requested| or TaskEnvironment controls mock time.
bool MaybeFastForwardToNextTask(bool quit_when_idle_requested) override {
if (quit_when_idle_requested)
return false;
return FastForwardToNextTaskOrCap(TimeTicks::Max()) ==
NextTaskSource::kMainThread;
}
const char* GetName() const override { return "MockTimeDomain"; }
// TickClock implementation:
TimeTicks NowTicks() const override { return Now(); }
// Used by FastForwardToNextTaskOrCap() to return which task source time was
// advanced to.
enum class NextTaskSource {
// Out of tasks under |fast_forward_cap|.
kNone,
// There's now >=1 immediate task on the main thread.
kMainThread,
// There's now >=1 immediate task in the thread pool.
kThreadPool,
};
// Advances time to the first of : next main thread task, next thread pool
// task, or |fast_forward_cap| (if it's not Max()).
NextTaskSource FastForwardToNextTaskOrCap(TimeTicks fast_forward_cap) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
// We don't need to call ReclaimMemory here because
// DelayTillNextTask will have dealt with cancelled delayed tasks for us.
Optional<TimeTicks> next_main_thread_task_time = NextScheduledRunTime();
// Consider the next thread pool tasks iff they're running.
Optional<TimeTicks> next_thread_pool_task_time;
if (thread_pool_ && thread_pool_task_tracker_->TasksAllowedToRun()) {
next_thread_pool_task_time =
thread_pool_->NextScheduledRunTimeForTesting();
}
// Custom comparison logic to consider nullopt the largest rather than
// smallest value. Could consider using TimeTicks::Max() instead of nullopt
// to represent out-of-tasks?
Optional<TimeTicks> next_task_time;
if (!next_main_thread_task_time) {
next_task_time = next_thread_pool_task_time;
} else if (!next_thread_pool_task_time) {
next_task_time = next_main_thread_task_time;
} else {
next_task_time =
std::min(*next_main_thread_task_time, *next_thread_pool_task_time);
}
if (next_task_time && *next_task_time <= fast_forward_cap) {
{
AutoLock lock(now_ticks_lock_);
// It's possible for |next_task_time| to be in the past in the following
// scenario:
// Start with Now() == 100ms
// Thread A : Post 200ms delayed task T (construct and enqueue)
// Thread B : Construct 20ms delayed task U
// => |delayed_run_time| == 120ms.
// Thread A : FastForwardToNextTaskOrCap() => fast-forwards to T @
// 300ms (task U is not yet in queue).
// Thread B : Complete enqueue of task U.
// Thread A : FastForwardToNextTaskOrCap() => must stay at 300ms and run
// U, not go back to 120ms.
// Hence we need std::max() to protect again this because construction
// and enqueuing isn't atomic in time (LazyNow support in
// base/task/thread_pool could help).
now_ticks_ = std::max(now_ticks_, *next_task_time);
}
if (next_task_time == next_thread_pool_task_time) {
// Let the thread pool know that it should post its now ripe delayed
// tasks.
thread_pool_->ProcessRipeDelayedTasksForTesting();
return NextTaskSource::kThreadPool;
}
return NextTaskSource::kMainThread;
}
if (!fast_forward_cap.is_max()) {
AutoLock lock(now_ticks_lock_);
// It's possible that Now() is already beyond |fast_forward_cap| when the
// caller nests multiple FastForwardBy() calls.
now_ticks_ = std::max(now_ticks_, fast_forward_cap);
}
return NextTaskSource::kNone;
}
private:
SEQUENCE_CHECKER(sequence_checker_);
sequence_manager::SequenceManager* const sequence_manager_;
internal::ThreadPoolImpl* thread_pool_ = nullptr;
const TestTaskTracker* thread_pool_task_tracker_ = nullptr;
// Protects |now_ticks_|
mutable Lock now_ticks_lock_;
// Only ever written to from the main sequence. Start from real Now() instead
// of zero to give a more realistic view to tests.
TimeTicks now_ticks_ GUARDED_BY(now_ticks_lock_){
base::subtle::TimeTicksNowIgnoringOverride()};
};
TaskEnvironment::MockTimeDomain*
TaskEnvironment::MockTimeDomain::current_mock_time_domain_ = nullptr;
TaskEnvironment::TaskEnvironment(
TimeSource time_source,
MainThreadType main_thread_type,
ThreadPoolExecutionMode thread_pool_execution_mode,
ThreadingMode threading_mode,
ThreadPoolCOMEnvironment thread_pool_com_environment,
bool subclass_creates_default_taskrunner,
trait_helpers::NotATraitTag)
: main_thread_type_(main_thread_type),
thread_pool_execution_mode_(thread_pool_execution_mode),
threading_mode_(threading_mode),
thread_pool_com_environment_(thread_pool_com_environment),
subclass_creates_default_taskrunner_(subclass_creates_default_taskrunner),
sequence_manager_(
CreateSequenceManagerForMainThreadType(main_thread_type)),
mock_time_domain_(
time_source != TimeSource::SYSTEM_TIME
? MockTimeDomain::CreateAndRegister(sequence_manager_.get())
: nullptr),
time_overrides_(time_source == TimeSource::MOCK_TIME
? std::make_unique<subtle::ScopedTimeClockOverrides>(
&MockTimeDomain::GetTime,
&MockTimeDomain::GetTimeTicks,
nullptr)
: nullptr),
mock_clock_(mock_time_domain_ ? std::make_unique<TickClockBasedClock>(
mock_time_domain_.get())
: nullptr),
scoped_lazy_task_runner_list_for_testing_(
std::make_unique<internal::ScopedLazyTaskRunnerListForTesting>()),
// TODO(https://crbug.com/922098): Enable Run() timeouts even for
// instances created with TimeSource::MOCK_TIME.
run_loop_timeout_(
mock_time_domain_
? nullptr
: std::make_unique<ScopedRunLoopTimeout>(
FROM_HERE,
TestTimeouts::action_timeout(),
BindRepeating(&sequence_manager::SequenceManager::
DescribeAllPendingTasks,
Unretained(sequence_manager_.get())))) {
CHECK(!base::ThreadTaskRunnerHandle::IsSet());
// If |subclass_creates_default_taskrunner| is true then initialization is
// deferred until DeferredInitFromSubclass().
if (!subclass_creates_default_taskrunner) {
task_queue_ = sequence_manager_->CreateTaskQueue(
sequence_manager::TaskQueue::Spec("task_environment_default")
.SetTimeDomain(mock_time_domain_.get()));
task_runner_ = task_queue_->task_runner();
sequence_manager_->SetDefaultTaskRunner(task_runner_);
simple_task_executor_ = std::make_unique<SimpleTaskExecutor>(task_runner_);
CHECK(base::ThreadTaskRunnerHandle::IsSet())
<< "ThreadTaskRunnerHandle should've been set now.";
CompleteInitialization();
}
if (threading_mode_ != ThreadingMode::MAIN_THREAD_ONLY)
InitializeThreadPool();
if (thread_pool_execution_mode_ == ThreadPoolExecutionMode::QUEUED &&
task_tracker_) {
CHECK(task_tracker_->DisallowRunTasks());
}
}
void TaskEnvironment::InitializeThreadPool() {
CHECK(!ThreadPoolInstance::Get())
<< "Someone has already installed a ThreadPoolInstance. If nothing in "
"your test does so, then a test that ran earlier may have installed "
"one and leaked it. base::TestSuite will trap leaked globals, unless "
"someone has explicitly disabled it with "
"DisableCheckForLeakedGlobals().";
ThreadPoolInstance::InitParams init_params(kNumForegroundThreadPoolThreads);
init_params.suggested_reclaim_time = TimeDelta::Max();
#if defined(OS_WIN)
if (thread_pool_com_environment_ == ThreadPoolCOMEnvironment::COM_MTA) {
init_params.common_thread_pool_environment =
ThreadPoolInstance::InitParams::CommonThreadPoolEnvironment::COM_MTA;
}
#endif
auto task_tracker = std::make_unique<TestTaskTracker>();
task_tracker_ = task_tracker.get();
auto thread_pool = std::make_unique<internal::ThreadPoolImpl>(
std::string(), std::move(task_tracker));
if (mock_time_domain_)
mock_time_domain_->SetThreadPool(thread_pool.get(), task_tracker_);
ThreadPoolInstance::Set(std::move(thread_pool));
ThreadPoolInstance::Get()->Start(init_params);
}
void TaskEnvironment::CompleteInitialization() {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
#if defined(OS_POSIX) || defined(OS_FUCHSIA)
if (main_thread_type() == MainThreadType::IO) {
file_descriptor_watcher_ =
std::make_unique<FileDescriptorWatcher>(GetMainThreadTaskRunner());
}
#endif // defined(OS_POSIX) || defined(OS_FUCHSIA)
}
TaskEnvironment::TaskEnvironment(TaskEnvironment&& other) = default;
TaskEnvironment::~TaskEnvironment() {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
// If we've been moved then bail out.
if (!owns_instance_)
return;
for (auto& observer : GetDestructionObservers())
observer.WillDestroyCurrentTaskEnvironment();
DestroyThreadPool();
task_queue_ = nullptr;
NotifyDestructionObserversAndReleaseSequenceManager();
}
void TaskEnvironment::DestroyThreadPool() {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
if (threading_mode_ == ThreadingMode::MAIN_THREAD_ONLY)
return;
// Ideally this would RunLoop().RunUntilIdle() here to catch any errors or
// infinite post loop in the remaining work but this isn't possible right now
// because base::~MessageLoop() didn't use to do this and adding it here would
// make the migration away from MessageLoop that much harder.
// Without FlushForTesting(), DeleteSoon() and ReleaseSoon() tasks could be
// skipped, resulting in memory leaks.
task_tracker_->AllowRunTasks();
ThreadPoolInstance::Get()->FlushForTesting();
ThreadPoolInstance::Get()->Shutdown();
ThreadPoolInstance::Get()->JoinForTesting();
// Destroying ThreadPoolInstance state can result in waiting on worker
// threads. Make sure this is allowed to avoid flaking tests that have
// disallowed waits on their main thread.
ScopedAllowBaseSyncPrimitivesForTesting allow_waits_to_destroy_task_tracker;
ThreadPoolInstance::Set(nullptr);
}
sequence_manager::TimeDomain* TaskEnvironment::GetTimeDomain() const {
return mock_time_domain_ ? mock_time_domain_.get()
: sequence_manager_->GetRealTimeDomain();
}
sequence_manager::SequenceManager* TaskEnvironment::sequence_manager() const {
DCHECK(subclass_creates_default_taskrunner_);
return sequence_manager_.get();
}
void TaskEnvironment::DeferredInitFromSubclass(
scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
task_runner_ = std::move(task_runner);
sequence_manager_->SetDefaultTaskRunner(task_runner_);
CompleteInitialization();
}
void TaskEnvironment::NotifyDestructionObserversAndReleaseSequenceManager() {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
// A derived classes may call this method early.
if (!sequence_manager_)
return;
if (mock_time_domain_)
sequence_manager_->UnregisterTimeDomain(mock_time_domain_.get());
sequence_manager_.reset();
}
scoped_refptr<base::SingleThreadTaskRunner>
TaskEnvironment::GetMainThreadTaskRunner() {
DCHECK(task_runner_);
return task_runner_;
}
bool TaskEnvironment::MainThreadIsIdle() const {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
sequence_manager::internal::SequenceManagerImpl* sequence_manager_impl =
static_cast<sequence_manager::internal::SequenceManagerImpl*>(
sequence_manager_.get());
// ReclaimMemory sweeps canceled delayed tasks.
sequence_manager_impl->ReclaimMemory();
return sequence_manager_impl->IsIdleForTesting();
}
void TaskEnvironment::RunUntilIdle() {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
if (threading_mode_ == ThreadingMode::MAIN_THREAD_ONLY) {
RunLoop(RunLoop::Type::kNestableTasksAllowed).RunUntilIdle();
return;
}
// TODO(gab): This can be heavily simplified to essentially:
// bool HasMainThreadTasks() {
// if (message_loop_)
// return !message_loop_->IsIdleForTesting();
// return mock_time_task_runner_->NextPendingTaskDelay().is_zero();
// }
// while (task_tracker_->HasIncompleteTasks() || HasMainThreadTasks()) {
// base::RunLoop().RunUntilIdle();
// // Avoid busy-looping.
// if (task_tracker_->HasIncompleteTasks())
// PlatformThread::Sleep(TimeDelta::FromMilliSeconds(1));
// }
// Update: This can likely be done now that MessageLoop::IsIdleForTesting()
// checks all queues.
//
// Other than that it works because once |task_tracker_->HasIncompleteTasks()|
// is false we know for sure that the only thing that can make it true is a
// main thread task (TaskEnvironment owns all the threads). As such we can't
// racily see it as false on the main thread and be wrong as if it the main
// thread sees the atomic count at zero, it's the only one that can make it go
// up. And the only thing that can make it go up on the main thread are main
// thread tasks and therefore we're done if there aren't any left.
//
// This simplification further allows simplification of DisallowRunTasks().
//
// This can also be simplified even further once TaskTracker becomes directly
// aware of main thread tasks. https://crbug.com/660078.
const bool could_run_tasks = task_tracker_->AllowRunTasks();
for (;;) {
task_tracker_->AllowRunTasks();
// First run as many tasks as possible on the main thread in parallel with
// tasks in ThreadPool. This increases likelihood of TSAN catching
// threading errors and eliminates possibility of hangs should a
// ThreadPool task synchronously block on a main thread task
// (ThreadPoolInstance::FlushForTesting() can't be used here for that
// reason).
RunLoop(RunLoop::Type::kNestableTasksAllowed).RunUntilIdle();
// Then halt ThreadPool. DisallowRunTasks() failing indicates that there
// were ThreadPool tasks currently running. In that case, try again from
// top when DisallowRunTasks() yields control back to this thread as they
// may have posted main thread tasks.
if (!task_tracker_->DisallowRunTasks())
continue;
// Once ThreadPool is halted. Run any remaining main thread tasks (which
// may have been posted by ThreadPool tasks that completed between the
// above main thread RunUntilIdle() and ThreadPool DisallowRunTasks()).
// Note: this assumes that no main thread task synchronously blocks on a
// ThreadPool tasks (it certainly shouldn't); this call could otherwise
// hang.
RunLoop(RunLoop::Type::kNestableTasksAllowed).RunUntilIdle();
// The above RunUntilIdle() guarantees there are no remaining main thread
// tasks (the ThreadPool being halted during the last RunUntilIdle() is
// key as it prevents a task being posted to it racily with it determining
// it had no work remaining). Therefore, we're done if there is no more work
// on ThreadPool either (there can be ThreadPool work remaining if
// DisallowRunTasks() preempted work and/or the last RunUntilIdle() posted
// more ThreadPool tasks).
// Note: this last |if| couldn't be turned into a |do {} while();|. A
// conditional loop makes it such that |continue;| results in checking the
// condition (not unconditionally loop again) which would be incorrect for
// the above logic as it'd then be possible for a ThreadPool task to be
// running during the DisallowRunTasks() test, causing it to fail, but then
// post to the main thread and complete before the loop's condition is
// verified which could result in HasIncompleteUndelayedTasksForTesting()
// returning false and the loop erroneously exiting with a pending task on
// the main thread.
if (!task_tracker_->HasIncompleteTaskSourcesForTesting())
break;
}
// The above loop always ends with running tasks being disallowed. Re-enable
// parallel execution before returning if it was allowed at the beginning of
// this call.
if (could_run_tasks)
task_tracker_->AllowRunTasks();
}
void TaskEnvironment::FastForwardBy(TimeDelta delta) {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
DCHECK(mock_time_domain_);
DCHECK_GE(delta, TimeDelta());
const bool could_run_tasks = task_tracker_ && task_tracker_->AllowRunTasks();
const TimeTicks fast_forward_until = mock_time_domain_->NowTicks() + delta;
do {
RunUntilIdle();
} while (mock_time_domain_->FastForwardToNextTaskOrCap(fast_forward_until) !=
MockTimeDomain::NextTaskSource::kNone);
if (task_tracker_ && !could_run_tasks)
task_tracker_->DisallowRunTasks();
}
void TaskEnvironment::FastForwardUntilNoTasksRemain() {
// TimeTicks::operator+(TimeDelta) uses saturated arithmetic so it's safe to
// pass in TimeDelta::Max().
FastForwardBy(TimeDelta::Max());
}
void TaskEnvironment::AdvanceClock(TimeDelta delta) {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
DCHECK(mock_time_domain_);
DCHECK_GE(delta, TimeDelta());
mock_time_domain_->AdvanceClock(delta);
}
const TickClock* TaskEnvironment::GetMockTickClock() const {
DCHECK(mock_time_domain_);
return mock_time_domain_.get();
}
base::TimeTicks TaskEnvironment::NowTicks() const {
DCHECK(mock_time_domain_);
return mock_time_domain_->Now();
}
const Clock* TaskEnvironment::GetMockClock() const {
DCHECK(mock_clock_);
return mock_clock_.get();
}
size_t TaskEnvironment::GetPendingMainThreadTaskCount() const {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
// ReclaimMemory sweeps canceled delayed tasks.
sequence_manager_->ReclaimMemory();
return sequence_manager_->GetPendingTaskCountForTesting();
}
TimeDelta TaskEnvironment::NextMainThreadPendingTaskDelay() const {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
// ReclaimMemory sweeps canceled delayed tasks.
sequence_manager_->ReclaimMemory();
DCHECK(mock_time_domain_);
Optional<TimeTicks> run_time = mock_time_domain_->NextScheduledRunTime();
if (run_time)
return *run_time - mock_time_domain_->Now();
return TimeDelta::Max();
}
bool TaskEnvironment::NextTaskIsDelayed() const {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
TimeDelta delay = NextMainThreadPendingTaskDelay();
return !delay.is_zero() && !delay.is_max();
}
void TaskEnvironment::DescribePendingMainThreadTasks() const {
DCHECK_CALLED_ON_VALID_THREAD(main_thread_checker_);
LOG(INFO) << sequence_manager_->DescribeAllPendingTasks();
}
// static
void TaskEnvironment::AddDestructionObserver(DestructionObserver* observer) {
GetDestructionObservers().AddObserver(observer);
}
// static
void TaskEnvironment::RemoveDestructionObserver(DestructionObserver* observer) {
GetDestructionObservers().RemoveObserver(observer);
}
TaskEnvironment::TestTaskTracker::TestTaskTracker()
: internal::ThreadPoolImpl::TaskTrackerImpl(std::string()),
can_run_tasks_cv_(&lock_),
task_completed_cv_(&lock_) {
// Consider threads blocked on these as idle (avoids instantiating
// ScopedBlockingCalls and confusing some //base internals tests).
can_run_tasks_cv_.declare_only_used_while_idle();
task_completed_cv_.declare_only_used_while_idle();
}
bool TaskEnvironment::TestTaskTracker::AllowRunTasks() {
AutoLock auto_lock(lock_);
const bool could_run_tasks = can_run_tasks_;
can_run_tasks_ = true;
can_run_tasks_cv_.Broadcast();
return could_run_tasks;
}
bool TaskEnvironment::TestTaskTracker::TasksAllowedToRun() const {
AutoLock auto_lock(lock_);
return can_run_tasks_;
}
bool TaskEnvironment::TestTaskTracker::DisallowRunTasks() {
AutoLock auto_lock(lock_);
// Can't disallow run task if there are tasks running.
if (num_tasks_running_ > 0) {
// Attempt to wait a bit so that the caller doesn't busy-loop with the same
// set of pending work. A short wait is required to avoid deadlock
// scenarios. See DisallowRunTasks()'s declaration for more details.
task_completed_cv_.TimedWait(TimeDelta::FromMilliseconds(1));
return false;
}
can_run_tasks_ = false;
return true;
}
void TaskEnvironment::TestTaskTracker::RunTask(internal::Task task,
internal::TaskSource* sequence,
const TaskTraits& traits) {
{
AutoLock auto_lock(lock_);
while (!can_run_tasks_)
can_run_tasks_cv_.Wait();
++num_tasks_running_;
}
{
// Using TimeTicksNowIgnoringOverride() because in tests that mock time,
// Now() can advance very far very fast, and that's not a problem. This is
// watching for tests that have actually long running tasks which cause our
// test suites to run slowly.
base::TimeTicks before = base::subtle::TimeTicksNowIgnoringOverride();
internal::ThreadPoolImpl::TaskTrackerImpl::RunTask(std::move(task),
sequence, traits);
base::TimeTicks after = base::subtle::TimeTicksNowIgnoringOverride();
if ((after - before) > TestTimeouts::action_max_timeout()) {
ADD_FAILURE() << "TaskEnvironment: RunTask took more than "
<< TestTimeouts::action_max_timeout().InSeconds()
<< " seconds. "
<< "Posted from " << task.posted_from.ToString();
}
}
{
AutoLock auto_lock(lock_);
CHECK_GT(num_tasks_running_, 0);
CHECK(can_run_tasks_);
--num_tasks_running_;
task_completed_cv_.Broadcast();
}
}
} // namespace test
} // namespace base