fix(optimizer): prevent hang if server closed quickly

[bluwy]

Description

In a specific case where a Vite server is started up progammatically and quickly closed, if new dependencies were discovered while so, server.close() promise will hang because the discovered dependency promises were never resolved, particularly here (which hangs _pendingRequests):

vite/packages/vite/src/node/plugins/optimizedDeps.ts

Lines 49 to 52 in 088d24b

	try {
	// This is an entry point, it may still not be bundled
	await info.processing
	} catch {

I found the issue that resolveEnqueuedProcessingPromises() wasn't called after the server is closing, so I called it. However there's another issue where if it also started a new discovered batch:

vite/packages/vite/src/node/optimizer/optimizer.ts

Lines 291 to 301 in 088d24b

	function startNextDiscoveredBatch() {
	newDepsDiscovered = false
	// Add the current depOptimizationProcessing to the queue, these
	// promises are going to be resolved once a rerun is committed
	depOptimizationProcessingQueue.push(depOptimizationProcessing)
	// Create a new promise for the next rerun, discovered missing
	// dependencies will be assigned this promise from this point
	depOptimizationProcessing = promiseWithResolvers()
	}

The new depOptimizationProcessing wasn't being resolved since it's not added to depOptimizationProcessingQueue. So I flipped line 296 and 300.

---

After these changes, it seem to fix the issue, however it's hard for me to create a test for this scenario 😅 I tested this on the Astro test fixtures: withastro/astro@0b3f1ac (#10833)

I'm not familiar with this area of code, let me know if I had misunderstood the flow and depOptimizationProcessingQueue's usecase.

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[bluwy]

Hmm I don't quite understand why the tests is failing (as it worked locally for me). I'll try to investigate soon but if not, I don't think it's a big need to get this fixed.

[bluwy]

Closing for now