Directory symlink results in EISDIR failure

[ConradHughes]

Whenever my source tree contains a symlink to a directory, pretty-quick fails after trying to read a directory as if it were a file:

$ mkdir foo
$ ln -s foo bar
$ npx pretty-quick --staged --check
...
Error: EISDIR: illegal operation on a directory, read
    at Object.readSync (node:fs:741:18)
    at LineByLine._readChunk (file:///.../node_modules/prettier/index.mjs:9439:27)
    at LineByLine.next (file:///.../node_modules/prettier/index.mjs:9465:28)
    at getInterpreter (file:///.../node_modules/prettier/index.mjs:17230:29)
    at getLanguageByInterpreter (file:///.../node_modules/prettier/index.mjs:17271:23)
    at inferParser (file:///.../node_modules/prettier/index.mjs:17286:192)
    at getParser (file:///.../node_modules/prettier/index.mjs:17317:55)
    at async getFileInfo (file:///.../node_modules/prettier/index.mjs:17305:22)
    at async /.../node_modules/pretty-quick/lib/isSupportedExtension.js:8:22
    at async Promise.all (index 14) {
  errno: -21,
  code: 'EISDIR',
  syscall: 'read'

Running strace --follow-forks --output-separately -o fail.log npx pretty-quick ... helped pin down the offending syscall (grep the log files for = -1 EISDIR).

[JounQin]

It seems thrown from prettier?

Would you like to raise a PR instead?

pretty-quick/src/isSupportedExtension.ts

Line 13 in b5e00ba

const fileInfo = await getFileInfo(file, {

We should ensure wether it's a symlinked directory here.

[ConradHughes]

Hi @JounQin, in principle I think it just needs if (!fs.existsSync(file) || !fs.statSync(file)?.isFile()) return false; and some adjustments to tests, but even on a clean repo yarn test fails for me, so I'm not sure where to go from there, sorry..

$ yarn test
 PASS  test/pretty-quick.spec.ts
 PASS  test/isSupportedExtension.spec.ts
 FAIL  test/scm-hg.spec.ts
  ● with hg › calls onFoundChangedFiles with changed files

    ENOENT: no such file or directory, open '/foo.js'

      29 |       filepath: file,
      30 |     }
    > 31 |     const input = fs.readFileSync(file, 'utf8')
         |                      ^
      32 |
      33 |     if (check) {
      34 |       const isFormatted = await prettierCheck(input, options)

      at readFileSync (src/processFiles.ts:31:22)
      at Object.<anonymous>.module.exports (src/index.ts:78:3)
      at Object.<anonymous> (test/scm-hg.spec.ts:109:5)

[JounQin]

@ConradHughes Hi, I just upgraded some deps on master branch, and all tests run well on my machine and CI (node 20/22 added), can you pull and retry?

I'd prefer async fs.stat(file) instead.

[ConradHughes]

Hi @JounQin, how does this look to you? My first proposal (to return false if the file doesn't exist) broke all of the git and hg tests, and fixing them seemed pretty tricky, so I now only return false if the file exists and is a directory.