public void Unlocked_PermitsMultipleReaderLocks()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
await rwl.ReaderLockAsync();
await rwl.ReaderLockAsync();
});
}
public void WriteLocked_PreventsReaderLock()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
await rwl.WriterLockAsync();
var task = rwl.ReaderLockAsync().AsTask();
await AssertEx.NeverCompletesAsync(task);
});
}
public void ReaderKey_MultiDispose_DoesNothing()
{
AsyncContext.Run(async () =>
{
var rwl = new AsyncReaderWriterLock();
var key = await rwl.ReaderLockAsync();
key.Dispose();
key.Dispose();
await rwl.ReaderLockAsync();
});
}
public void ReaderLocked_UpgradableReaderReleased_UpgradableReaderWaiting_ReleasesUpgrableReader()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
Task upgradableReadLock;
using (await rwl.ReaderLockAsync())
using (await rwl.UpgradeableReaderLockAsync())
{
upgradableReadLock = rwl.UpgradeableReaderLockAsync().AsTask();
Assert.IsFalse(upgradableReadLock.IsCompleted);
}
await upgradableReadLock;
});
}
public void UpgradeableKey_MultiUpgradeWhenFirstUpgradeIsIncomplete_ThrowsSynchronousException()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
await rwl.ReaderLockAsync();
var key = await rwl.UpgradeableReaderLockAsync();
var _ = key.UpgradeAsync();
AssertEx.ThrowsException<InvalidOperationException>(() => key.UpgradeAsync());
});
}
public void ReaderLocked_ReaderReleased_ReaderAndWriterWaiting_DoesNotReleaseReaderOrWriter()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
Task readLock, writeLock;
await rwl.ReaderLockAsync();
using (await rwl.ReaderLockAsync())
{
writeLock = rwl.WriterLockAsync().AsTask();
readLock = rwl.ReaderLockAsync().AsTask();
}
await TaskShim.WhenAll(AssertEx.NeverCompletesAsync(writeLock),
AssertEx.NeverCompletesAsync(readLock));
});
}
public void ReaderLocked_ReaderReleased_ReaderAndUpgradingReaderWaiting_DoesNotReleaseReaderOrUpgradingReader()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
Task readLock, upgradingReadLock;
await rwl.ReaderLockAsync();
using (await rwl.ReaderLockAsync())
{
var upgradeableReadLock = await rwl.UpgradeableReaderLockAsync();
upgradingReadLock = upgradeableReadLock.UpgradeAsync().AsTask();
readLock = rwl.ReaderLockAsync().AsTask();
}
await TaskShim.WhenAll(AssertEx.NeverCompletesAsync(upgradingReadLock),
AssertEx.NeverCompletesAsync(readLock));
});
}
public void LockReleased_WriteTakesPriorityOverRead()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
Task writeLock, readLock;
using (await rwl.WriterLockAsync())
{
readLock = rwl.ReaderLockAsync().AsTask();
writeLock = rwl.WriterLockAsync().AsTask();
}
await writeLock;
await AssertEx.NeverCompletesAsync(readLock);
});
}
public void LockReleased_AllowsUpgradeableReadAndMultipleReaders()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
Task upgradeableReadLock, readLock1, readLock2;
using (await rwl.WriterLockAsync())
{
upgradeableReadLock = rwl.UpgradeableReaderLockAsync().AsTask();
readLock1 = rwl.ReaderLockAsync().AsTask();
readLock2 = rwl.ReaderLockAsync().AsTask();
}
await TaskShim.WhenAll(upgradeableReadLock, readLock1, readLock2);
});
}
public void ReadLocked_PreventsWriterLock()
{
AsyncContext.Run(async () =>
{
var rwl = new AsyncReaderWriterLock();
await rwl.ReaderLockAsync();
var task = rwl.WriterLockAsync();
await AssertEx.NeverCompletesAsync(task);
});
}
public void WriteLocked_ReaderLockCancelled_DoesNotTakeLockWhenUnlocked()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
using (await rwl.WriterLockAsync())
{
var cts = new CancellationTokenSource();
var task = rwl.ReaderLockAsync(cts.Token).AsTask();
cts.Cancel();
await AssertEx.ThrowsExceptionAsync<OperationCanceledException>(() => task);
}
await rwl.ReaderLockAsync();
});
}
public void ReaderLock_PreCancelled_LockAvailable_SynchronouslyTakesLock()
{
var rwl = new AsyncReaderWriterLock();
var token = new CancellationToken(true);
var task = rwl.ReaderLockAsync(token).AsTask();
Assert.IsTrue(task.IsCompleted);
Assert.IsFalse(task.IsCanceled);
Assert.IsFalse(task.IsFaulted);
}
public void Upgrade_PreCancelled_LockNotAvailable_SynchronouslyCancels()
{
var rwl = new AsyncReaderWriterLock();
var token = new CancellationToken(true);
var key = rwl.UpgradeableReaderLockAsync().AsTask().Result;
rwl.ReaderLockAsync();
var task = key.UpgradeAsync(token).AsTask();
Assert.IsTrue(task.IsCompleted);
Assert.IsTrue(task.IsCanceled);
Assert.IsFalse(task.IsFaulted);
}
public void UpgradeableReadLocked_Downgrade_AllowsReaderLock()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
var key = await rwl.UpgradeableReaderLockAsync();
var upgradeKey = await key.UpgradeAsync();
upgradeKey.Dispose();
await rwl.ReaderLockAsync();
});
}
public void UpgradeableReadAndReadLocked_UpgradeAborted_CompletesAsCanceled()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
var readLockTaken = new TaskCompletionSource();
var task = TaskShim.Run(async () =>
{
using (await rwl.ReaderLockAsync())
{
readLockTaken.SetResult();
await TaskConstants.Never;
}
});
await readLockTaken.Task;
Task upgradeTask;
using (var key = await rwl.UpgradeableReaderLockAsync())
{
upgradeTask = key.UpgradeAsync().AsTask();
Assert.IsFalse(key.Upgraded);
}
await AssertEx.ThrowsExceptionAsync<OperationCanceledException>(upgradeTask);
});
}
public void UpgradeableReadAndReadLocked_Upgrade_WaitsForReaderLockToUnlock()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
var readLockTaken = new TaskCompletionSource();
var releaseReadLock = new TaskCompletionSource();
var task = TaskShim.Run(async () =>
{
using (await rwl.ReaderLockAsync())
{
readLockTaken.SetResult();
await releaseReadLock.Task;
}
});
await readLockTaken.Task;
using (var key = await rwl.UpgradeableReaderLockAsync())
{
Assert.IsFalse(key.Upgraded);
var lockTask = key.UpgradeAsync().AsTask();
Assert.IsFalse(lockTask.IsCompleted);
releaseReadLock.SetResult();
await lockTask;
Assert.IsTrue(key.Upgraded);
}
});
}
public void UpgradeableReadLocked_AllowsMultipleReaderLocks()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
var key = await rwl.UpgradeableReaderLockAsync();
Assert.IsFalse(key.Upgraded);
await rwl.ReaderLockAsync();
await rwl.ReaderLockAsync();
});
}
public void ReadLocked_AllowsUpgradeableReaderLock()
{
Test.Async(async () =>
{
var rwl = new AsyncReaderWriterLock();
await rwl.ReaderLockAsync();
await rwl.UpgradeableReaderLockAsync();
});
}