Replace abandoned tree-kill library (Issue with --watch on MacOS)

[gcstarr]

Is there an existing issue that is already proposing this?

• I have searched the existing issues

Is your feature request related to a problem? Please describe it

NestJS CLI uses tree-kill for its --watch functionality. The tree-kill library has been abandoned for 6 years and recently has started having issues running on MacOS v15+ (Sequoia and up), potentially more likely in mono-repos with large amounts of files (I'm unable to reproduce in a simple Hello World project). The issue is that when a change is detected, an EBADF error occurs when tree-kill tries to kill the running processes.

See this issue in the tree-kill repo, and this conversation with yaacov and @micalevisk in NestJS's Discord server.

Describe the solution you'd like

The main options are to use one of the forks of tree-kill that has had this issue patched, of course risking that the forked library will also be abandoned, or to remove the external dependency entirely. Both approaches work, I've provided examples here and tested that both resolve my issues on MacOS Sequoia 15.5:

Use forked tree-kill example: master...gcstarr:nest-cli:use-tree-kill-fork

Remove external dependency example (was AI assisted as I was looking for a quick feasibility check, though I have tested it in both MacOS and Linux, but not Windows yet): master...gcstarr:nest-cli:remove-tree-kill

Thoughts?

Teachability, documentation, adoption, migration strategy

No response

What is the motivation / use case for changing the behavior?

Removing abandoned dependency that is becoming more problematic.

[kamilmysliwiec]

Would you like to create a PR for this issue? I'd say bringing the code of this package into the @nestjs/cli would be ideal (instead of relying on other external libraries)

[gcstarr]

Yeah I can do that. I just need to do some review and cleaning up and check it on a Windows box. 👍

[gcstarr]

@kamilmysliwiec Now that I understand the code a bit better, I'm wondering if this could just be as simple as: ba183c0? The local tree-kill.ts you already have is using execSync which fixes the issue (The use of spawn in the original tree-kill library is what doesn't work well sometimes with newer MacOS builds).

[kamilmysliwiec]

Yeah this should be enough indeed, great catch

[gcstarr]

OK, I have the PR up. Unfortunately for me this ultimately doesn't resolve the issues I'm seeing with nest start --watch using TSC, file descriptors, EBADF errors, and a large mono-repo, but that ultimately may not be something that needs fixing in NestJS CLI itself as I investigate more. If it is I'll be back with another PR 😁. But hopefully pulling out the tree-kill dependency that's using spawn instead of execSync will make this issue less likely to happen for others.