"IndexError: list index out of range" on all files in folder

[adamklaff]

I'm running black via pipx, and I am getting this on every file I run black on in my project folder. If I move the file outside my project folder, it will process. Any ideas?

Traceback (most recent call last):
File "/Users/user1/.local/bin/black", line 8, in
sys.exit(patched_main())
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/black/init.py", line 1128, in patched_main
main()
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/click/core.py", line 1137, in call
return self.main(*args, **kwargs)
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/click/core.py", line 1062, in main
rv = self.invoke(ctx)
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/click/core.py", line 1404, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/click/core.py", line 763, in invoke
return __callback(*args, **kwargs)
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/click/decorators.py", line 26, in new_func
return f(get_current_context(), *args, **kwargs)
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/black/init.py", line 410, in main
sources = get_sources(
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/black/init.py", line 476, in get_sources
gitignore = get_gitignore(root)
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/black/files.py", line 123, in get_gitignore
return PathSpec.from_lines("gitwildmatch", lines)
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/pathspec/pathspec.py", line 95, in from_lines
lines = [pattern_factory(line) for line in lines if line]
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/pathspec/pathspec.py", line 95, in
lines = [pattern_factory(line) for line in lines if line]
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/pathspec/pattern.py", line 83, in init
regex, include = self.pattern_to_regex(pattern)
File "/Users/user1/.local/pipx/venvs/black/lib/python3.9/site-packages/pathspec/patterns/gitwildmatch.py", line 112, in pattern_to_regex
if not pattern_segs[-1] and len(pattern_segs) > 1:
IndexError: list index out of range

[adamklaff]

This was due to a misconfigured .gitignore file. Fixed.

[ichard26]

It's great you were able to fix the issue on your own @adamklaff but that uncaught exception + traceback probably wasn't the most easy thing to debug I can imagine! For that I've opened a new issue asking for a more user-friendly error to be emitted when the .gitignore related code blows up :) #2359

Thanks for the report and therefore idea!

[SebastiaanZ]

@adamklaff I was looking into your bug and I wasn't able to reproduce it. Do you happen to have the fragment of your .gitignore file that triggers the exception? I want to provide a nice solution for #2359.

Edit: A line with a single backslash (\) reproduces the exception.

[adamklaff]

The last line just had a “/“ by itself

…

On Jul 9, 2021, at 5:39 AM, Sebastiaan Zeeff ***@***.***> wrote:  @adamklaff I was looking into your bug and I wasn't able to reproduce it. Do you happen to have the fragment of your .gitignore file that triggers the exception? I want to provide a nice solution for #2359. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or unsubscribe.