public void WriteLock_should_be_exclusive()
{
var lockId = Guid.NewGuid().ToString();
using var readWriteLock1 = new TinyReadWriteLock(lockId, 2, TimeSpan.FromMilliseconds(0));
using var readWriteLock2 = new TinyReadWriteLock(lockId, 2, TimeSpan.FromMilliseconds(0));
// Aquire the first lock
readWriteLock1.AcquireWriteLock();
// The second lock should now throw TimeoutException
Should.Throw <TimeoutException>(() => readWriteLock2.AcquireWriteLock());
// Make sure the expected locks are held
readWriteLock1.IsWriterLockHeld.ShouldBeTrue();
readWriteLock2.IsWriterLockHeld.ShouldBeFalse();
// By releasing the first lock, the second lock should now be able to be held
readWriteLock1.ReleaseWriteLock();
readWriteLock2.AcquireWriteLock();
// Make sure the expected locks are held
readWriteLock1.IsWriterLockHeld.ShouldBeFalse();
readWriteLock2.IsWriterLockHeld.ShouldBeTrue();
}
public void Calling_ReleaseWriteLock_should_release_locks()
{
using var readWriteLock = new TinyReadWriteLock(Guid.NewGuid().ToString(), 2);
readWriteLock.AcquireWriteLock();
readWriteLock.IsWriterLockHeld.ShouldBeTrue();
readWriteLock.ReleaseWriteLock();
readWriteLock.IsWriterLockHeld.ShouldBeFalse();
}
public void Calling_AcquireWriteLock_then_AquireReadLock_should_wait_for_other_lock()
{
var lockId = Guid.NewGuid().ToString();
using var readWriteLock1 = new TinyReadWriteLock(lockId, 2);
using var readWriteLock2 = new TinyReadWriteLock(lockId, 2);
readWriteLock1.AcquireWriteLock();
var readLockTask = Task.Run(() => readWriteLock2.AcquireReadLock());
WaitForTaskToStart(readLockTask);
readWriteLock1.IsWriterLockHeld.ShouldBeTrue();
readWriteLock2.IsReaderLockHeld.ShouldBeFalse();
readWriteLock1.ReleaseWriteLock();
readLockTask.Wait();
readWriteLock1.IsWriterLockHeld.ShouldBeFalse();
readWriteLock2.IsReaderLockHeld.ShouldBeTrue();
}
public void Calling_ReleaseWriteLock_without_any_lock_held_should_throw()
{
using var readWriteLock = new TinyReadWriteLock(Guid.NewGuid().ToString(), 1);
Should.Throw <SemaphoreFullException>(() => readWriteLock.ReleaseWriteLock());
}