Do nothing if the half edge array is empty.

[fire]

Let's see if this fixes the bug.

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[elalish]

What bug was this fixing? Can you add a test case to demonstrate?

[fire]

I don't have the test case on hard, it was with an empty manifold.

[elalish]

Can you please add a test so we know what problem we're fixing? You should be able to copy this one and tweak slightly: https://github.com/elalish/manifold/blob/master/test/mesh_test.cpp#L608

[fire]

I'm not able to work on this much because of siggraph 2022 this week.

[elalish]

Got it, no prob. I'm curious, mostly :)

[fire]

I wasn't able to get myself to work on this. Godot Engine 4 work has been tiring.