fix(optimizer): check .vite/deps directory existence before removing

[jeromehan]

Potential fix for #9986

[benmccann]

This workaround still seems susceptible to race conditions even if it causes them to occur less frequently

[bluwy]

This workaround still seems susceptible to race conditions even if it causes them to occur less frequently

Are you referring to the race condition within the optimizer in general? I think @patak-dev solved that one before. This fix seems like the likely reason why it still happens even with Patak's fix though.

[benmccann]

I believe the root cause of #9986 is that the optimizer can run twice in parallel and so trying to do the rename twice fails (#9986 (comment)). I think there'd still be some possibility for that to occur even after this PR. It seems like this code can't be written in a way that's fully blocking because gracefulRename calls setTimeout which will invoke the event loop. Because processing is handed off to the event loop, the other optimizer job can attempt the rename at the same time causing a failure.

I think the real fix would be to prevent the optimizer from running twice in parallel. That seems like it would also be better for performance as well if we can cancel the initial job (evanw/esbuild#2725). It's also a more involved fix though

I'm not sure what fix of @patak-dev's you're referring to. As far as I know, nothing has been fixed, but I don't follow development nearly as closely as you do, so very well may have missed it.

[patak-dev]

This is the PR that @bluwy is referencing:

• fix: properly close optimizer on server restart #10028

I think we can still merge this PR, but avoid closing the linked issue. Let's first review avoiding running the optimizer in parallel.