@tus/s3-store: ensure promise rejection isn't uncaught

[itslenny]

This PR fixes a fairly rare uncaught exception issue that I've had occur in production resulting in a fatal error / node crash. I can reproduce this locally by doing TUS uploads and intentionally disrupting traffic to S3.

This issue occurs when one of the deferred promises throws before getting to the Promise.all which node identifies as an uncaught exception. This only happens if pendingChunkFilepath is not null in the catch block which causes the async operation await fsProm.rm(pendingChunkFilepath) to run which advances the event loop causing node to recognize the uncaught exception before Promise.all is awaited.

I've also added a test that reproduces the issue consistently. You can comment out my fix and run the new test to see the uncaught exception.

[changeset-bot]

🦋 Changeset detected

Latest commit: f983077

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@tus/s3-store	Patch

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[coderabbitai]

Walkthrough

Changes were made to prevent unhandled promise rejections in the S3Store's uploadParts method by adding a .catch() handler to deferred promises. A new test case verifies that no unhandled rejections occur when uploads fail, and a changeset file documents the patch version bump.

Changes

Cohort / File(s)	Summary
Metadata .changeset/modern-spoons-behave.md	Added changeset entry for @tus/s3-store with patch version bump documenting deferred promise rejection handling.
Promise Rejection Handling packages/s3-store/src/index.ts	Added .catch(() => { /\* ignore \*/ }) handler to per-chunk deferred promises in uploadParts to prevent unhandled rejections before the later Promise.all* call.
Test Coverage packages/s3-store/src/test/index.ts	Added test case verifying no unhandledRejection event is triggered when an upload fails quickly, using stubbed uploadPart method and a self-destroying readable stream.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• @tus/s3-store: fix unhandled promise rejection #728 — Modifies the same packages/s3-store/src/index.ts file with related promise rejection handling and failing upload test coverage.

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description check	✅ Passed	The PR description provides clear context about the issue (uncaught exception in production), root cause (deferred promise rejection before Promise.all, with async operation advancing event loop), and solution, plus mentions a test that reproduces the issue.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Title check	✅ Passed	The PR title clearly and specifically describes the main change: preventing uncaught promise rejections in the S3 store implementation, which matches the primary objective of fixing a fatal Node process crash caused by unhandled promise rejections.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[Murderlon]

Nice catch! Thanks