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It looks like the unit test failures are related.

Yes, and failure means that the updates to run_test are enabling metal validation.

Neat, I didn't think to enable this on a per test basis.

These tests are passing on an M1 but not on the CI x64 machines, need to figure out whether we can suppor tthis API in that configuration or not.

Oh goodness Iw as looking at the wrong test.

Unfortunately, the updated env vars to run_tests.py do not trigger failures without this change. However, adding the ones that Xcode uses trigger many other failures that seem not quite right.

I'm going to land this to at least get the existing tests working on development machines. Maybe we can figure out how to make this work across architectures and on CI separate from this patch.