Better handle signals in tsc CLI

[Jake Bailey (jakebailey)]

See also #4592
Fixes microsoft/TypeScript#63856

[Daniel Rosenwasser (DanielRosenwasser)]

Wasn't part of the original intent for handling signals to do something special during profiling?

[Copilot]

Pull request overview

Restores default OS signal handling for the tsc CLI so SIGINT and SIGTERM terminate immediately.

Changes:

• Removes CLI signal interception.
• Uses a background context for compilation; API and LSP handling remain unchanged.

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[Jake Bailey (jakebailey)]

Yeah.... but the only way that would work is if we profile watch mode. Otherwise we'd just let it go to exit.

I don't think it's worth it for now if it hangs Ctrl+C; we can invent a mode which does cancellation if profiling isn't running or add our own exit hooks (like Go does!). But that's more complicated.

[Luke Sandberg (lukesandberg)]

per my testing (see comment: #4592 (comment)) this will cause odd panics if you ctrl-c a watch mode build

here is my attempt at this same idea that avoids the 'all goroutines are blocked' issue

main...lukesandberg:typescript-go:lukesandberg/no_signal_handler_for_compile

[Jake Bailey (jakebailey)]

That's plausible, but that platform code would belong in osutil.

[Jake Bailey (jakebailey)]

Feel free to open it, I just assumed you wouldn't reply so quickly 😄

[Luke Sandberg (lukesandberg)]

I don't have permissions to open PRs anymore

[Jake Bailey (jakebailey)]

If you restore the branch in #4592, I can reopen it

[Luke Sandberg (lukesandberg)]

dd5868e is on a different branch
you can just cherry pick it if you want it

[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

Suppressed comments (1)

internal/execute/tsc.go:126

• This new signal/watch path has no regression coverage. Because this change fixes a process-level interruption bug, add subprocess tests that send SIGINT/SIGTERM and verify normal compilation, watch mode, and profiling terminate promptly without the watch deadlock and that profiling flushes its output before exit.

	if buildCommand.CompilerOptions.Watch.IsTrue() && !profiled && options.WatchContext != nil {
		var stop context.CancelFunc
		ctx, stop = options.WatchContext(ctx)
		defer stop()

[Jake Bailey (jakebailey)]

I'm going to just defer this until after the repo move.

[Ryan Cavanaugh (RyanCavanaugh)]

Thank you for contributing to the TypeScript native port!

Development has moved from this repository back to the main microsoft/TypeScript repository. GitHub does not have PR transfer functionality, so we're closing this PR here.

If this change is still relevant, please reopen it as a new pull request in microsoft/TypeScript. We'd appreciate your help carrying the contribution over, and we apologize for the extra work.

See microsoft/typescript-go#4918 for more information about the move.