maximum recursion depth exceeded while calling a Python object

[trumpet2012]

Describe the bug

When running black using pre-commit against a generated Django migration file, the following error is observed:

➜  backend git:(main) ✗ pre-commit run black --all-files             
black....................................................................Failed
- hook id: black
- exit code: 123

error: cannot format backend/src/black_test.py: maximum recursion depth exceeded while calling a Python object

Oh no! 💥 💔 💥
167 files left unchanged, 1 file failed to reformat.

To Reproduce

Here is a file that can reproduce the above issue: https://gist.github.com/trumpet2012/057e1e6bc381081e06a2eaf9e22db45a

Install pre-commit: https://pre-commit.com/index.html#installation

Our pre-commit config is:

default_language_version:
  python: python3
exclude: (^|/)\.idea/
repos:
  - repo: https://github.com/psf/black
    rev: 22.10.0
    hooks:
      - id: black
        args:
          # enable preview mode to get the new string processing
          - --preview

Then running:

$ pre-commit run black --all-files

Results in the above error.

Expected behavior

Black should be able to correctly reformat the file.

Environment

• Black's version: 22.10.0
• OS and Python version: Mac OS Monterey, Python 3.9.14
• pre-commit version: 2.20.0

Additional context
It works when you run black without the --preview flag.

Interestingly, it also works running black directly (bypassing pre-commit) even with the --preview flag enabled.

Also when I was generating the example file above, I was going through and replacing our internal column names and help text with fake data and when I replaced the help_text= strings with just Lorem ipsum dolores it also worked correctly. Increasing the length of the help text strings then caused the issue to reappear.

[hauntsaninja]

Thanks for the report!

I believe pre-commit doesn't use wheels, which might explain some of your reproducibility issues (e.g. maybe there's some interaction with mypyc). I can reproduce on main with my editably installed checkout with --preview. Doesn't look like a recent regression either.

The stacktrace (visible by using -v) is just a bunch of:

  File "/Users/shantanu/dev/black/src/black/linegen.py", line 504, in transform_line
    result = run_transformer(line, transform, mode, features, line_str=line_str)
  File "/Users/shantanu/dev/black/src/black/linegen.py", line 1217, in run_transformer
    result.extend(transform_line(transformed_line, mode=mode, features=features))
  File "/Users/shantanu/dev/black/src/black/linegen.py", line 504, in transform_line
    result = run_transformer(line, transform, mode, features, line_str=line_str)
  File "/Users/shantanu/dev/black/src/black/linegen.py", line 1217, in run_transformer
    result.extend(transform_line(transformed_line, mode=mode, features=features))

Edit: earlier version of this comment claimed it reproduced without --preview. It does need --preview, I just put the file inside black's dir, so we used --preview automatically.

[hauntsaninja]

Goes back at least all the way to ESP being added to preview (this issue should probably get an ESP label)