Makes me think that we might want to add a CI check that would git diff --exit-code to ensure that vendored modules were correctly generated, whenever anything in vendors or src/poetry/core/_vendor is updated, as a safety measure.

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I'm not sure I follow how such a check would work -- re-run the vendoring and check there is no diff?

I'm not sure I follow how such a check would work -- re-run the vendoring and check there is no diff?

Yep, that would be the main idea. I'd be happy to set up a quick POC for this.

I think at this point, go ahead and do it -- when my long-running CI rework comes to fruition for each repo, I can just incorporate it.