Unity Muse Graph unable to open after upgrading from 22.3.4 to 22.3.17f1

[ChrisKurhan]

This morning I created a relatively simple behavior graph in Unity 2022.3.4. After upgrading editor version to 2022.3.17, the graph no longer can be edited (shows an empty graph window) and I get the following 2 errors in console:

Exception thrown while invoking [OnOpenAssetAttribute] method ‘Unity.Muse.Behavior.BehaviorAuthoringGraph:step1 (int,int)’ : NullReferenceException: Object reference not set to an instance of an object
Unity.Muse.Behavior.EventNodeModel.EnsureFieldValuesAreUpToDate () (at ./Library/PackageCache/com.unity.muse.behavior@0.5.11/Runtime/Asset/Models/EventNodeModel.cs:58)
Unity.Muse.Behavior.BehaviorGraphNodeModel.OnValidate () (at ./Library/PackageCache/com.unity.muse.behavior@0.5.11/Runtime/Asset/Models/BehaviorGraphNodeModel.cs:50)
Graph.GraphAsset.OnValidate () (at ./Library/PackageCache/com.unity.muse.behavior@0.5.11/Tools/Graph/Asset/GraphAsset.cs:83)
Unity.Muse.Behavior.BehaviorAuthoringGraph.OnValidate () (at ./Library/PackageCache/com.unity.muse.behavior@0.5.11/Runtime/Asset/BehaviorAuthoringGraph.cs:68)
Graph.GraphEditor.Load (Graph.GraphAsset asset) (at ./Library/PackageCache/com.unity.muse.behavior@0.5.11/GraphEditor.cs:90)
…truncated
[Worker0] NullReferenceException: Object reference not set to an instance of an object
Unity.Muse.Behavior.EventNodeModel.EnsureFieldValuesAreUpToDate () (at ./Library/PackageCache/com.unity.muse.behavior@0.5.11/Runtime/Asset/Models/EventNodeModel.cs:58)
Unity.Muse.Behavior.BehaviorGraphNodeModel.OnValidate () (at ./Library/PackageCache/com.unity.muse.behavior@0.5.11/Runtime/Asset/Models/BehaviorGraphNodeModel.cs:50)
Graph.GraphAsset.OnValidate () (at ./Library/PackageCache/com.unity.muse.behavior@0.5.11/Tools/Graph/Asset/GraphAsset.cs:83)
Unity.Muse.Behavior.BehaviorAuthoringGraph.OnValidate () (at ./Library/PackageCache/com.unity.muse.behavior@0.5.11/Runtime/Asset/BehaviorAuthoringGraph.cs:68)

Unclear if it’s related to the version upgrade or not, but that’s the only thing that changed.
Happy to provide a .unitypackage with the graph and related scripts

[ShaneeNishry]

Hey Chris!

Thank you for reporting this. Does the error go away if you revert back to 2022.3.4? I’m going to try and make a graph and update between these 2 specific versions although I’ve been upgrading versions quite a bit (mostly in the 2023.2 line) without this issue, so it’d be good to find a reliable repro.

Also, do you have any new nodes in this graph or is it all nodes that come with the package?

Thanks!

[ChrisKurhan]

I don’t think this is related to the upgrade, but I’ve sent over that .unitypackage via Phillip so hopefully that provides a concrete example that can lead to a fix. Sounds like the asset somehow got corrupted.