nodejs / nodejs/node

test_runner: `t.after` should respect `the first-in-last-out` principle like Golang's defer

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feature request test_runner
Dominant language
JavaScript
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Avg merge
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Merged PRs (30d)
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Description

Version

v22.10.0

Platform

No response

Subsystem

No response

What steps will reproduce the bug?
1. Create a test file
import fs from 'node:fs'
import path from 'node:path'
import test from 'node:test'

test('basic', async (t) => {
    const testDir = path.join(import.meta.dirname, 'logs')

    fs.mkdirSync(testDir, { recursive: true })

    t.after(() => {
        console.log('remove test dir')
        fs.rmdirSync(testDir, { recursive: true })
    })

    fs.writeFileSync(path.join(testDir, 'test.log'), 'hello world!')

    t.after(() => {
        console.log('remove test file')
        fs.unlinkSync(path.join(testDir, 'test.log'))
    })

    // do staff...
})
How often does it reproduce? Is there a required condition?

None

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

t.after should follow the first-in, last-out principle

According to the above code, the file should be deleted first, then the directory

What do you see instead?
✖ basic (7.4021ms)
  Error: ENOENT: no such file or directory, unlink 'project\folder\logs\test.log'
      at Object.unlinkSync (node:fs:1871:11)
      at TestContext.<anonymous> (file:///path/to/test.test.mjs:19:12)
      at TestHook.runInAsyncScope (node:async_hooks:211:14)
      at TestHook.run (node:internal/test_runner/test:934:25)
      at TestHook.run (node:internal/test_runner/test:1225:18)
      at TestHook.run (node:internal/util:543:20)
      at node:internal/test_runner/test:853:20
      at async Test.runHook (node:internal/test_runner/test:851:7)
      at async after (node:internal/test_runner/test:893:9)
      at async Test.run (node:internal/test_runner/test:942:7) {
Additional information

the first-in-last-out principle is more reasonable and practical. It is useful in many scenarios.

I'm not sure why it was designed in the form of a queue. Is there anything special about it?

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Reproduce the behavior with the provided test case, then trace cleanup from the node:internal/test_runner stack frames, especially TestHook.run and after. Done means callbacks execute in reverse registration order so the file is removed before its directory, with coverage for the reported ordering.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript, node.js
Domain
testing-qa
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Quiet
Clarity
Mostly clear
Newbie friendliness
55/100

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