Bug when running lint-staged in git worktree

[bantic]

Description

Reproduced using version 10.0.4.

The lint-staged "prepare" step fails when it is run inside a git worktree because the worktree doesn't have a local .git directory, it has a .git file instead. When the "prepare" step runs it fails with a message like:

$ git commit -m 'test'
husky > pre-commit (node v10.18.1)
  ✖ Preparing...
    → fatal: could not open '/Volumes/code/the-worktree-dir/.git/lint-staged_unstaged.patch' for writing: Not a directory
  ↓ Running tasks... [skipped]
    → Skipped because of previous git error.
  ↓ Applying modifications... [skipped]
    → Skipped because of previous git error.
  ↓ Cleaning up... [skipped]
    → Skipped because of previous git error.

  ✖ lint-staged failed due to a git error.
  Any lost modifications can be restored from a git stash:

    > git stash list
    stash@{0}: On master: automatic lint-staged backup
    > git stash pop stash@{0}

fatal: could not open '/Volumes/code/the-worktree-dir/.git/lint-staged_unstaged.patch' for writing: Not a directory

Steps to reproduce

The following steps should reproduce this for any checked-out repo that is set up with lint-staged:

• create a worktree: git worktree add ../some-other-path
• cd ../some-other-path
• Install deps, etc. npm install
• Edit a file then attempt to commit it

I created an example repo that serves as a minimal reproduction: https://github.com/bantic/try-lint-staged

Debug Logs

expand to view

git commit -m 'test'
husky > pre-commit (node v10.18.1)
  lint-staged:bin Running `lint-staged@10.0.4` +0ms
  lint-staged:bin Options parsed from command-line: { allowEmpty: false,
  concurrent: true,
  configPath: undefined,
  debug: true,
  maxArgLength: 131072,
  quiet: false,
  relative: false,
  shell: false } +2ms
  lint-staged Loading config using `cosmiconfig` +0ms
  lint-staged Successfully loaded config from `/Volumes/code/other-page/lint-staged.config.js`:
  lint-staged { '*.js': 'eslint --fix' } +12ms
  lint-staged:cfg Validating config +0ms
Running lint-staged with the following config:
{
  '*.js': 'eslint --fix'
}
  lint-staged:run Running all linter scripts +0ms
  lint-staged:git Running git command [ 'rev-parse', '--show-toplevel' ] +0ms
  lint-staged:git Running git command [ 'rev-parse', '--show-superproject-working-tree' ] +12ms
  lint-staged:run Resolved git directory to be `/Volumes/code/other-page` +24ms
  lint-staged:run Resolved git config directory to be `/Volumes/code/other-page/.git` +1ms
  lint-staged:git Running git command [ 'diff', '--staged', '--diff-filter=ACMR', '--name-only' ] +12ms
  lint-staged:run Loaded list of staged files in git:
  lint-staged:run [ 'abc.js', 'package.json' ] +7ms
  lint-staged:chunkFiles Resolved an argument string length of 69 characters from 2 files +0ms
  lint-staged:chunkFiles Creating 1 chunks for maxArgLength of 131072 +0ms
  lint-staged:gen-tasks Generating linter tasks +0ms
  lint-staged:gen-tasks Generated task:
  lint-staged:gen-tasks { pattern: '*.js',
  lint-staged:gen-tasks   commands: 'eslint --fix',
  lint-staged:gen-tasks   fileList: [ '/Volumes/code/other-page/abc.js' ] } +2ms
  lint-staged:make-cmd-tasks Creating listr tasks for commands 'eslint --fix' +0ms
  lint-staged:task cmd: eslint +0ms
  lint-staged:task args: [ '--fix' ] +0ms
  lint-staged:task execaOptions: { preferLocal: true, reject: false, shell: false } +0ms
Preparing... [started]
  lint-staged:git Backing up original state... +0ms
  lint-staged:git Backing up merge state... +1ms
  lint-staged:file Reading buffer from file `/Volumes/code/other-page/.git/MERGE_HEAD` +0ms
  lint-staged:file Reading buffer from file `/Volumes/code/other-page/.git/MERGE_MODE` +0ms
  lint-staged:file Reading buffer from file `/Volumes/code/other-page/.git/MERGE_MSG` +0ms
  lint-staged:file Done reading buffer from file `/Volumes/code/other-page/.git/MERGE_HEAD`! +1ms
  lint-staged:file Done reading buffer from file `/Volumes/code/other-page/.git/MERGE_MODE`! +0ms
  lint-staged:file Done reading buffer from file `/Volumes/code/other-page/.git/MERGE_MSG`! +0ms
  lint-staged:git Done backing up merge state! +1ms
  lint-staged:git Running git command [ 'stash',
  'save',
  '--include-untracked',
  '--keep-index',
  'lint-staged automatic backup' ] +16ms
  lint-staged:git Restoring merge state... +66ms
  lint-staged:git Done restoring merge state! +0ms
  lint-staged:git Running git command [ 'ls-files', '--others', '--exclude-standard' ] +66ms
  lint-staged:git Running git command [ 'stash', 'list' ] +7ms
  lint-staged:git Running git command [ 'diff',
  '--binary',
  '--unified=0',
  '--no-color',
  '--no-ext-diff',
  '--patch',
  '--output=/Volumes/code/other-page/.git/lint-staged_unstaged.patch',
  'stash@{0}',
  '-R' ] +16ms
Preparing... [failed]
→ fatal: could not open '/Volumes/code/other-page/.git/lint-staged_unstaged.patch' for writing: Not a directory
Running tasks... [started]
Running tasks... [skipped]
→ Skipped because of previous git error.
Applying modifications... [started]
Applying modifications... [skipped]
→ Skipped because of previous git error.
Cleaning up... [started]
Cleaning up... [skipped]
→ Skipped because of previous git error.

  ✖ lint-staged failed due to a git error.
  Any lost modifications can be restored from a git stash:

    > git stash list
    stash@{0}: On master: automatic lint-staged backup
    > git stash pop stash@{0}

fatal: could not open '/Volumes/code/other-page/.git/lint-staged_unstaged.patch' for writing: Not a directory
husky > pre-commit hook failed (add --no-verify to bypass)

Environment

• OS: macOS Mojave v10.14.6
• Node.js: v10.18.1
• lint-staged: v10.0.4

[iiroj]

Thanks for the report! We do a similar thing for the submodules. I guess some reading is in order to find the correct location: https://git-scm.com/docs/git-worktree#_details

[bantic]

Thanks for the quick reply! Yes, the contents of the .git dir in the worktree point to the location in the $GIT_COMMON_DIR, like so:

$ pwd
/absolute/path/to/my-repo
$ git worktree add ../other-path
$ cd ../other-path
$ cat .git
gitdir: /absolute/path/to/my-repo/.git/worktrees/other-path

I was looking at the code and looks like the fix may be as straightforward as modifying the gitConfigDir argument — for cases where the .git is a file and not a directory — when instantiating a GitWorkflow: https://github.com/okonet/lint-staged/blob/master/lib/gitWorkflow.js#L44

[iiroj]

I opened a PR #784 that fixes this issue by always parsing the gitConfigDir by reading from .git when it's a file.

[okonet]

🎉 This issue has been resolved in version 10.0.5 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[bantic]

👏 I'm impressed how quickly this was fixed. Thank you!

[okonet]

@bantic thanks! You can express how impressed you are here https://opencollective.com/lint-staged ;)