Add --fix-to-stdout back

[mantoni]

This includes the work from @DamienCassou made in #298 with more unit tests and documentation.

Fixes #295

[mantoni]

This is very frustrating. It's always the same integration test failing, always on some other version of eslint, and I cannot reproduce locally.

[L2jLiga]

and I cannot reproduce locally.

I think you can try clean linux environment? It's reproducible on my machine - this test fails with random eslint version

my setup is:
Ubuntu 24.04 server minimal
nodejs 22 installed with nvm

then I just cloned this branch, run npm ci, then npm test:integration -- --timeout 10000

[L2jLiga]

This is what I get from stderr:

 node:net:1296
    validatePort(port);
    ^

RangeError [ERR_SOCKET_BAD_PORT]: Port should be >= 0 and < 65536. Received type number (NaN).
    at lookupAndConnect (node:net:1296:5)
    at Socket.connect (node:net:1253:5)
    at Object.connect (node:net:236:17)
    at forwardToDaemon (file:///home/user/eslint_d.js/lib/forwarder.js:41:22)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async file:///home/user/eslint_d.js/bin/eslint_d.js:67:7 {
  code: 'ERR_SOCKET_BAD_PORT'
}

[L2jLiga]

config content: { token: '', port: NaN, pid: NaN, hash: undefined }

[L2jLiga]

I've added check here that port not valid, now seems to not having any issues with exactly this test:

eslint_d.js/bin/eslint_d.js

Line 61 in b34fea1

if (!config) {

but another appeared:

  1) integration tests
       v8.0.x
         stop:
     Error: Timeout of 100000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves. (/home/user/eslint_d.js/test/test.integration.js)
      at listOnTimeout (node:internal/timers:581:17)
      at process.processTimers (node:internal/timers:519:7)

[L2jLiga]

I've added check here that port not valid, now seems to not having any issues with exactly this test:

eslint_d.js/bin/eslint_d.js

Line 61 in b34fea1

if (!config) {

Well, just adding check didn't help, issue is really flaky, sometime it pass, sometime no, now it has no errors and still fails, I guess it might be that daemon / eslint crashes for some reasons and that's why there's no output 🤔

[RayGuo-ergou]

Weird I am also on linux but cannot reproduce the issue.

❯ cat /etc/lsb-release
───────┬────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
       │ File: /etc/lsb-release
───────┼────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   1   │ DISTRIB_ID=Ubuntu
   2   │ DISTRIB_RELEASE=22.04
   3   │ DISTRIB_CODENAME=jammy
   4   │ DISTRIB_DESCRIPTION="Ubuntu 22.04.4 LTS"
───────┴────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

❯ nr
✔ script to run › test:integration

> [email protected] test:integration
> mocha --bail --slow 1000 test/test.integration.js



  ..................................................

  50 passing (3s)

[L2jLiga]

Are you on correct branch?

this branch contains 70 tests, in your output only 50

$ npm run test:integration -- --timeout 100000

> [email protected] test:integration
> mocha --bail --slow 1000 test/test.integration.js --timeout 100000



  ......................................................................

  70 passing (51s)

[RayGuo-ergou]

🫠Was interrupted by something and forget to change branch.

Yeah got the same error in cli

❯ nr
✔ script to run › test:integration

> [email protected] test:integration
> mocha --bail --slow 1000 test/test.integration.js



  ......................................................!

  54 passing (4s)
  1 failing

  1) integration tests
       --fix-to-stdout
         v6.0.x
           when file only contains fixable problems
             prints input if no change is needed:

      AssertionError: [assert.equals] '' expected to be equal to "console.log('Hello eslint');"
      + expected - actual

      +console.log('Hello eslint');

      at Object.fail (node_modules/@sinonjs/referee/lib/create-fail.js:5:21)
      at Object.fail (node_modules/@sinonjs/referee/lib/define-assertion/index.js:47:17)
      at assertion (node_modules/@sinonjs/referee/lib/define-assertion/index.js:65:11)
      at referee.<computed>.<computed> [as equals] (node_modules/@sinonjs/referee/lib/define-assertion/index.js:92:22)
      at Context.<anonymous> (file:///home/ray/git/eslint_d.js/test/test.integration.js:209:20)
      at process.processTicksAndRejections (node:internal/process/task_queues:95:5)

[L2jLiga]

No problem, to see error you could swap assets in test this way:

assert.isNull(error);
assert.equals(stderr, '');
assert.equals(stdout, '');

[L2jLiga]

Also if you run tests several time then some of runs could be successful, really weird

[RayGuo-ergou]

Same here tried run 10 times succeed once.

The version failed for me only 5 or 6, but saw 8 in CI.

[L2jLiga]

As a quick-fix solution we could use retry feature from mocha, long term this flaky test should be fixed
https://mochajs.org/#retry-tests

[L2jLiga]

but another appeared:

  1) integration tests
       v8.0.x
         stop:
     Error: Timeout of 100000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves. (/home/user/eslint_d.js/test/test.integration.js)
      at listOnTimeout (node:internal/timers:581:17)
      at process.processTimers (node:internal/timers:519:7)

Regarding this issue, for some weird reasons it stucks on fs.unlink for very long time (maybe forever), as a solution I've replaced fs.unlink with fs.rm(file, { force:true })

[L2jLiga]

        context('when file only contains fixable problems', () => {
          it('prints input if no change is needed', async () => {

replacing with

        context('when file only contains fixable problems', () => {
          it('prints input if no change is needed', async function() {
            this.retries(2);

makes this test much more robust in my environment

[mantoni]

@L2jLiga @RayGuo-ergou Thank you so much for helping debug this. It turns out that the startup sequence with file watches is quite aggressive regarding timings, so as far as I understand it now, it can happen that the config file appears on the file system, but the readFile call returns an empty string. Apparently the file appears but is not yet fully written. A short delay and re-reading the file seems to fix it.

[RayGuo-ergou]

Happy to help and @L2jLiga did all the work 😄.

And Hi @mantoni and @DamienCassou , I really want to say thank you for make this happening!

[mantoni]

📦 Released in v14.0.2