public async Task TestReleaseThenReAcquireWithConcurrentAccess()
{
var sut = new FastAsyncLock();
using (var otherThread = new AsyncTestRunner(OtherThread))
{
await otherThread.AdvanceTo(1);
Assert.IsTrue(otherThread.HasLock());
await otherThread.AdvanceTo(2);
Assert.IsFalse(otherThread.HasLock());
using (await sut.LockAsync(CancellationToken.None))
{
await Task.Yield();
await otherThread.AdvanceAndFreezeBefore(3);
Assert.IsFalse(otherThread.HasLock());
}
await otherThread.AdvanceTo(4);
Assert.IsTrue(otherThread.HasLock());
}
async Task OtherThread(CancellationToken ct, AsyncTestRunner r)
{
using (await sut.LockAsync(CancellationToken.None))
{
await Task.Yield();
r.HasLock(true);
r.Sync(position: 1);
}
await Task.Yield();
r.HasLock(false);
r.Sync(position: 2);
using (await sut.LockAsync(CancellationToken.None))
{
await Task.Yield();
r.HasLock(true);
r.Sync(position: 3);
r.Sync(position: 4);
}
await Task.Yield();
r.HasLock(false);
}
}
public async Task TestExitFromAnotherExecutionContext()
{
var sut = new FastAsyncLock();
var locking = default(IDisposable);
var entryContext = default(AsyncTestContext);
using (var externalThread = new AsyncTestRunner(ExternalThread))
{
entryContext = AsyncTestContext.Current;
locking = await sut.LockAsync(CancellationToken.None);
await externalThread.AdvanceTo(1);
Assert.IsTrue(externalThread.HasLock());
await externalThread.AdvanceToEnd();
}
async Task ExternalThread(CancellationToken ct, AsyncTestRunner r)
{
Assert.AreNotEqual(entryContext, AsyncTestContext.Current);
locking.Dispose();
// Try to relock from the external execution context to validate that the lock was effectively released
using (await sut.LockAsync(ct))
{
r.HasLock(true);
r.Sync(position: 1);
await Task.Yield();
}
r.HasLock(false);
}
}
[Ignore] // https://github.com/nventive/Uno.Core/issues/48
public async Task TestUnlockReleaseNextSynchronously()
{
Console.WriteLine($"Running on thread {Thread.CurrentThread.ManagedThreadId}");
var sut = new FastAsyncLock();
var thread1ExitingThread = -1;
var thread2LockingTask = default(Task <IDisposable>);
var thread1 = new AsyncTestRunner(Thread1);
var thread2 = new AsyncTestRunner();
thread2.Run(Thread2);
using (thread1)
using (thread2)
{
// Acquire the lock on thread 1
await thread1.AdvanceTo(1);
// Wait for the thread 2 to be stuck to acquire the lock
var thread2Locking = thread2.AdvanceTo(1);
while (thread2LockingTask == null)
{
await Task.Yield();
}
// Make sure that the thread 2 is really awaiting the thread2LockingTask before requesting thread1 to continue
await Task.Delay(100);
Assert.AreEqual(TaskStatus.WaitingForActivation, thread2LockingTask.Status);
// Relase the thread 1 and make sure that the thread 2 is able to acquire the lock
var thread1Release = thread1.AdvanceTo(2);
await thread2Locking;
}
async Task Thread1(CancellationToken ct, AsyncTestRunner r)
{
Console.WriteLine($"Thread 1: {Thread.CurrentThread.ManagedThreadId}");
var ctx = AsyncTestContext.Current;
using (await sut.LockAsync(ct))
{
Console.WriteLine($"Acquired lock for Thread1 on thread: {Thread.CurrentThread.ManagedThreadId}");
ctx.Validate();
await Task.Yield();
r.Sync(position: 1);
thread1ExitingThread = Thread.CurrentThread.ManagedThreadId;
Console.WriteLine($"Releasing lock from Thread1 on thread: {Thread.CurrentThread.ManagedThreadId}");
}
Console.WriteLine($"Released lock from Thread1 on thread: {Thread.CurrentThread.ManagedThreadId}");
// This must have run synchronously when lock got released (disposed).
Assert.AreEqual(TaskStatus.RanToCompletion, thread2LockingTask.Status);
r.Sync(position: 2);
}
async Task Thread2(CancellationToken ct, AsyncTestRunner r)
{
Console.WriteLine($"Thread 2: {Thread.CurrentThread.ManagedThreadId}");
var ctx = AsyncTestContext.Current;
thread2LockingTask = sut.LockAsync(ct);
// Validate that we are running on thread 2
Assert.AreEqual(thread2.ThreadId, Thread.CurrentThread.ManagedThreadId);
Console.WriteLine("Thread 2 is waiting for lock");
using (await thread2LockingTask)
{
Console.WriteLine($"Acquired lock for Thread2 on thread: {Thread.CurrentThread.ManagedThreadId}");
// Here we should run on the thread 1 since the lock is released synchronously from thread 1
Assert.AreEqual(thread1ExitingThread, Thread.CurrentThread.ManagedThreadId);
// But we should have kept the ExecutionContext from the thread 2
ctx.Validate();
await Task.Yield();
r.Sync(position: 1);
Console.WriteLine($"Releasing lock from Thread2 on thread: {Thread.CurrentThread.ManagedThreadId}");
}
Console.WriteLine($"Released lock from Thread2 on thread: {Thread.CurrentThread.ManagedThreadId}");
r.Sync(position: 2);
}
}
public async Task TestReEntrencyWithConcurrentAccess()
{
var sut = new FastAsyncLock();
using (var thread2 = new AsyncTestRunner(Thread2))
using (var thread1 = new AsyncTestRunner(Thread1))
{
// Enter from main thread
await thread1.AdvanceTo(1);
// Try enter from second thread
var thread2Locking = thread2.AdvanceTo(2);
await Task.Delay(100);
Assert.AreEqual(TaskStatus.WaitingForActivation, thread2Locking.Status);
// ReEnter
await thread1.AdvanceTo(2);
// Exit once
await thread1.AdvanceTo(3);
Assert.AreEqual(TaskStatus.WaitingForActivation, thread2Locking.Status);
// Final exit
thread1.AdvanceTo(4);
await thread2Locking;
}
async Task Thread1(CancellationToken ct, AsyncTestRunner r)
{
using (await sut.LockAsync(CancellationToken.None))
{
await Task.Yield();
r.HasLock(true);
r.Sync(position: 1);
using (await sut.LockAsync(CancellationToken.None))
{
await Task.Yield();
r.Sync(position: 2);
}
r.Sync(position: 3);
}
r.HasLock(false);
r.Sync(position: 4);
}
async Task Thread2(CancellationToken ct, AsyncTestRunner r)
{
using (await sut.LockAsync(ct))
{
r.HasLock(true);
r.Sync(position: 1);
}
r.HasLock(false);
r.Sync(position: 2);
}
}
public async Task TestConcurrentCancelSecondWithThird()
{
var sut = new FastAsyncLock();
var ct = new CancellationTokenSource();
var thread2LockingTask = default(Task <IDisposable>);
using (var thread1 = new AsyncTestRunner(Thread1))
using (var thread2 = new AsyncTestRunner(Thread2))
using (var thread3 = new AsyncTestRunner(Thread3))
{
// Acquire the lock on thread 1 THEN
await thread1.AdvanceTo(1);
Assert.IsTrue(thread1.HasLock());
// Try to acquire the lock from this async context
await thread2.AdvanceAndFreezeBefore(1);
//var locking = sut.LockAsync(ct.Token);
Assert.AreEqual(TaskStatus.WaitingForActivation, thread2LockingTask.Status);
Assert.IsFalse(thread2.HasLock());
// Try to acquire it on thread 3
var t3Locked = thread3.AdvanceTo(1);
await thread3.IsFrozen();
Assert.IsFalse(thread3.HasLock());
// But cancel before the other async context completes
ct.Cancel();
Assert.AreEqual(TaskStatus.Canceled, thread2LockingTask.Status);
// Release the lock from thread1, and wait for thread 3 to acquire the lock
await thread1.AdvanceAndFreezeBefore(2); // will freeze in continuation of thread 3
await t3Locked;
//Assert.IsFalse(thread1.HasLock()); // flag not set yet: the thread 1 is dead locked by the continuation of thread 3
Assert.IsTrue(thread3.HasLock());
await thread3.AdvanceToEnd();
//await thread1.AdvanceToEnd();
await Task.Delay(500);
Assert.IsFalse(thread1.HasLock());
Assert.IsFalse(thread3.HasLock());
}
async Task Thread1(CancellationToken ct2, AsyncTestRunner r)
{
using (await sut.LockAsync(ct2))
{
r.HasLock(true);
r.Sync(position: 1);
}
r.HasLock(false);
r.Sync(position: 2);
};
async Task Thread2(CancellationToken ct2, AsyncTestRunner r)
{
thread2LockingTask = sut.LockAsync(ct.Token);
using (await thread2LockingTask)
{
r.HasLock(true);
r.Sync(position: 1);
}
r.HasLock(false);
r.Sync(position: 2);
}
async Task Thread3(CancellationToken ct2, AsyncTestRunner r)
{
using (await sut.LockAsync(ct2))
{
r.HasLock(true);
r.Sync(position: 1);
}
r.HasLock(false);
r.Sync(position: 2);
};
}