The validationTokenSource should be set to null right after ValidateAsync is called. Otherwise, if the token is canceled (token.IsCancellationRequested is true) and therefore validationTokenSource is not set to null, next call to ResetValidationTokenSource will crash at line validationTokenSource?.Cancel() because validationTokenSource object is already disposed (see the using statement that creates the token). (#1694)

Co-authored-by: Kyle Tran <[email protected]>
Co-authored-by: Gerald Versluis <[email protected]>

Author: 3 people

src/CommunityToolkit/Xamarin.CommunityToolkit/Behaviors/Validators/ValidationBehavior.shared.cs

@@ -279,11 +279,11 @@ async ValueTask UpdateStateAsync(bool isForced, CancellationToken? parentToken =
 				try
 				{
 					var isValid = await ValidateAsync(Decorate(Value), token).ConfigureAwait(false);
+					validationTokenSource = null;
 
 					if (token.IsCancellationRequested)
 						return;
 
-					validationTokenSource = null;
 					IsValid = isValid;
 					IsRunning = false;
 				}