Graph Editor: crashes on `could not find a nodedef for node`

[marwie]

Hello,

I'm currently working on generating MaterialX graphs and naturally produce some invalid results.

When selecting some of those falsely produced nodes the editor crashes. Below is an example graph that produces a crash

Expected: Invalid graph nodes are marked in the graph and can be selected without crashing the editor Actual: When selecting invalid / not found graph nodes the editor crashes

<?xml version="1.0"?>
<materialx name="" version="1.38" >
    <nodegraph name="needle_shadergraph" >
        <input name="_MyColor" type="color3" value="0.8962264, 0.2494215, 0.2494215, 1.0" />
    </nodegraph>
    <standard_surface name="needle_standard_surface" type="surfaceshader" >
        <input name="SurfaceDescription.BaseColor" interfacename="_MyColor" />
        <input name="SurfaceDescription.Smoothness" type="float" value="1.0" />
        <input name="SurfaceDescription.Metallic" type="float" value="1.0" />
    </standard_surface>
    <surfacematerial name="Default" type="material" >
        <input name="surfaceshader" type="surfaceshader" nodename="needle_standard_surface" />
    </surfacematerial>
</materialx>

[jstone-lucasfilm]

Great catch, @marwie, and I believe that we should follow the approach in MaterialXView and display a warning dialog when this exception is caught in the Graph Editor, so that invalid input data never triggers a crash.

[jstone-lucasfilm]

@marwie I'm testing this in a local build of the main branch, and it looks like this issue is now resolved, where the user can select and dive into the nodes of your example material without a crash. Let us know how this works for you in your local builds.