[BUG] npm not handling process signals

Is there an existing issue for this?

• I have searched the existing issues

NOTE: I originally posted this issue on nodejs/node but was redirected here.

This issue exists in the latest npm version

• I am using the latest npm

Current Behavior

npm doesn't handle SIGTERM like it used to. I noticed this issue specifically when updating node from v20.2.0 to v20.3.0 (npm 9.6.7 to 9.8.1).

Expected Behavior

Expected that the below program exits with code 0 (i.e., npm is aborted by the signal and the script handles the signal as well)

Steps To Reproduce

The below script sends a SIGTERM to the npm process that spawned it. Run npm run test with:

In package.json

    {
      "name": "test",
      "version": "0.0.0",
      "type": "module",
      "scripts": {
        "test": "node test.js"
      }
    }

In test.js

    import { execSync } from 'child_process';

    process.on('SIGTERM', () => {
        console.log('Received SIGTERM. Exiting...');
        process.exit(0);
    });

    const output = execSync('ps -e | grep npm').toString().split(/\s+/).filter(Boolean);
    const pid = Number(output[0]);
    process.kill(pid)

    setTimeout(() => {
        console.log('Fatal: Signal was not received. Exiting... ');
        process.exit(1)
    }, 2000);

Environment

• npm: 9.8.0
• Node.js: v20.5.0
• OS Name: Linux nixos 5.15.93 x86_64 GNU/Linux
• System Model Name:
• npm config:

; node bin location = /nix/store/1gnvy2dhh311c900hzyw6ppjdhnir2s5-nodejs-20.5.0/bin/node
; node version = v20.5.0
; npm local prefix = /build
; npm version = 9.8.0
; cwd = /build
; HOME = /homeless-shelter
; Run `npm config ls -l` to show all defaults.

Start by running npm run test with the package.json and test.js reproduction on Linux, then trace how the npm process handles the SIGTERM sent by the script. Done means npm is aborted by the signal, the script's SIGTERM handler logs its message, and the program exits with code 0.