npm outdated unable to be run programmatically from child_process.execSync

[jrtitus]

Version

16.20.0, 18.6.0, 20.3.0

Platform

Linux --- 5.15.90.1-microsoft-standard-WSL2 nodejs/node#1 SMP Fri Jan 27 02:56:13 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

Subsystem

child_process

What steps will reproduce the bug?

const { execSync } = require('node:child_process');
const out = execSync('npm outdated --omit=dev --json');

How often does it reproduce? Is there a required condition?

Always. This also occurs with a request of execSync('npm outdated') (without flags).

What is the expected behavior? Why is that the expected behavior?

A Buffer including the results of npm outdated.

The example I'm using should have this output:

{
  "octokit": {
    "current": "2.0.19",
    "wanted": "2.0.21",
    "latest": "2.0.21",
    "dependent": "---",
    "location": "/home/---/src/---/node_modules/octokit"
  }
}

What do you see instead?

Uncaught Error: Command failed: npm outdated --omit=dev --json
    at __node_internal_genericNodeError (node:internal/errors:857:15)
    at checkExecSyncError (node:child_process:861:11)
    at execSync (node:child_process:932:15) {
  status: 1,
  signal: null,
  output: [
    null,
    <Buffer 7b 0a 20 20 22 6f 63 74 6f 6b 69 74 22 3a 20 7b 0a 20 20 20 20 22 63 75 72 72 65 6e 74 22 3a 20 22 32 2e 30 2e 31 39 22 2c 0a 20 20 20 20 22 77 61 6e ... 138 more bytes>,
    <Buffer >
  ],
  pid: 6610,
  stdout: <Buffer 7b 0a 20 20 22 6f 63 74 6f 6b 69 74 22 3a 20 7b 0a 20 20 20 20 22 63 75 72 72 65 6e 74 22 3a 20 22 32 2e 30 2e 31 39 22 2c 0a 20 20 20 20 22 77 61 6e ... 138 more bytes>,
  stderr: <Buffer >
}

Additional information

1. If you translate the stdout buffer from hex to ascii, it does have the correct data, but the call fails for some reason.
2. Other commands such as execSync('npm i'), execSync('npm audit'), execSync('npm config list --json'), etc. will succeed.

[richardlau]

cc @nodejs/npm

I believe this is working as designed. npm outdated exits with a non-zero exit code (status: 1 in the output) which causes execSync to throw an error.

Looks like there's some discussion about the npm behaviour in npm/rfcs#473.

[jrtitus]

@richardlau Thank you for the response.

At least now I understand how I can work around this. I didn't even consider that a non-zero exit code was expected when outdated packages are found because the command succeeds in retrieving information about them.

[github-actions]

It seems there has been no activity on this issue for a while, and it is being closed in 30 days. If you believe this issue should remain open, please leave a comment.
If you need further assistance or have questions, you can also search for similar issues on Stack Overflow.
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[github-actions]

It seems there has been no activity on this issue for a while, and it is being closed. If you believe this issue should remain open, please leave a comment.
If you need further assistance or have questions, you can also search for similar issues on Stack Overflow.
Make sure to look at the README file for the most updated links.