[BUG] Incorrect use of "?." operator causes exceptions.

[guyboots_thunderbroParticipant]

The exception:

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MissingReferenceException: The object of type 'MonoManager' has been destroyed but you are still trying to access it. Your script should either check if it is null or you should not destroy the object.

The source:

Node.cs#416, Task.cs#219, Task.cs#320,

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public Coroutine StartCoroutine(IEnumerator routine) {             return MonoManager.current?.StartCoroutine(routine);         }           ///Nodes can use coroutine as normal through MonoManager.         public void StopCoroutine(Coroutine routine) {             MonoManager.current?.StopCoroutine(routine);         }

The problem:

C#’s ?. operator doesn’t work with Unity Objects (UnityEngine.Object). So instead of backing off if MonoManager.current is null, this code is executed anyway, then triggers the UnityException above.

Note:

The list of problem areas isn’t exhaustive. Just what I noticed; I think a more thorough approach (EG “Find All”) is a good idea.

[guyboots_thunderbroParticipant]

Left this out of the original post, but: this only happens when Unity is unloading everything when exiting play mode, so it causes a flood of exceptions in the console that don’t mean anything but can hide other errors none-the-less.

[GavalakisKeymaster]

Hello again,

I will change those to normal null checks and do some further testing.

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///Tasks can start coroutine through MonoManager         protected Coroutine StartCoroutine(IEnumerator routine) {             return MonoManager.current != null ? MonoManager.current.StartCoroutine(routine) : null;         }           ///Tasks can start coroutine through MonoManager         protected void StopCoroutine(Coroutine routine) {             if ( MonoManager.current != null ) { MonoManager.current.StopCoroutine(routine); }         }

Thank you.

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