Black: setting line-length in pyproject.toml prevents Black from running in vim

[erikr]

Describe the bug

If line-length is set in pyproject.toml, running black in Vim fails and throws the following error:

'<=' not supported between instances of 'int' and 'str'

To Reproduce

The minimum example that reproduces the error for me:

├── pyproject.toml
└── test.py

The contents of pyproject.toml follow the same syntax as is provided by pyproject.toml in the black repo

[tool.black]
line-length = 79

The contents of test.py:

foo = 1

Running black in Vim on test.py throws the error:

'<=' not supported between instances of 'int' and 'str'

I can successfully run black on test.py outside of vim:

~/.vim/black/bin/black test.py

or

black test.py

If I comment out line-length in pyproject.toml, the error we see when calling black in Vim goes away:

[tool.black]
#line-length = 79

The problem seems to be how line-length is parsed and cast by black.

Expected behavior
black runs without errors, and utilizes the line-length value specified in pyproject.toml.

Environment (please complete the following information):

• Version: 19.10b0
• OS and Python version: macOS 10.15.5 and Python 3.8.3; also reproduced on Ubuntu 20.04 and Python 3.8.3.

Does this bug also happen on master?

To answer this, you have two options:

1. Use the online formatter at https://black.now.sh/?version=master, which will use the latest master branch.

n/a

1. Or run _Black_ on your machine:
   
   
   
   • create a new virtualenv (make sure it's the same Python version);
   
   
   • clone this repository;
   
   
   • run pip install -e .;
   
   
   • make sure it's sane by running python -m unittest; and
   
   
   • run black like you did last time.
   
   

I get errors running python -m unittest but unsure related to this bug:

$ python -m unittest                                                                                                                                   
E....[2020-06-14 14:22:15,341] DEBUG: Using selector: EpollSelector (selector_events.py:59)
.[2020-06-14 14:22:15,342] DEBUG: Using selector: EpollSelector (selector_events.py:59)
.[2020-06-14 14:22:15,680] DEBUG: Using selector: EpollSelector (selector_events.py:59)
.[2020-06-14 14:22:15,682] DEBUG: Using selector: EpollSelector (selector_events.py:59)
[2020-06-14 14:22:15,683] INFO: 16 projects to run Black over (lib.py:311)
[2020-06-14 14:22:15,683] DEBUG: Using 2 parallel workers to run Black (lib.py:316)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on aioexabgp (lib.py:247)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on attrs (lib.py:247)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on bandersnatch (lib.py:247)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on channels (lib.py:247)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on django (lib.py:247)
[2020-06-14 14:22:15,684] INFO: Skipping django as it's disabled via config (lib.py:254)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on flake8-bugbear (lib.py:247)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on hypothesis (lib.py:247)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on pandas (lib.py:247)
[2020-06-14 14:22:15,684] INFO: Skipping pandas as it's disabled via config (lib.py:254)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on poetry (lib.py:247)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on ptr (lib.py:247)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on pyramid (lib.py:247)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on pytest (lib.py:247)
[2020-06-14 14:22:15,684] INFO: Skipping pytest as it's disabled via config (lib.py:254)
[2020-06-14 14:22:15,684] DEBUG: worker 0 working on sqlalchemy (lib.py:247)
[2020-06-14 14:22:15,685] DEBUG: worker 0 working on tox (lib.py:247)
[2020-06-14 14:22:15,685] DEBUG: worker 0 working on virtualenv (lib.py:247)
[2020-06-14 14:22:15,685] DEBUG: worker 0 working on warehouse (lib.py:247)
[2020-06-14 14:22:15,685] DEBUG: project_runner 0 exiting (lib.py:245)
[2020-06-14 14:22:15,685] DEBUG: project_runner 1 exiting (lib.py:245)
[2020-06-14 14:22:15,685] INFO: Analyzing results (lib.py:327)
.
======================================================================
ERROR: tests.test_black (unittest.loader._FailedTest)
----------------------------------------------------------------------
ImportError: Failed to import test module: tests.test_black
Traceback (most recent call last):
  File "/home/username/miniconda3/envs/ml4sts/lib/python3.8/unittest/loader.py", line 436, in _find_test_path
    module = self._get_module_from_name(name)
  File "/home/username/miniconda3/envs/ml4sts/lib/python3.8/unittest/loader.py", line 377, in _get_module_from_name
    __import__(name)
  File "/home/erik/black/tests/test_black.py", line 1766, in <module>
    class BlackDTestCase(AioHTTPTestCase):
NameError: name 'AioHTTPTestCase' is not defined


----------------------------------------------------------------------
Ran 9 tests in 0.348s

FAILED (errors=1)

[ichard26]

I can fix this, I introduced this regression trying to fix #1458.

[cooperlees]

@ichard26 Is this at all related to https://github.com/psf/black/pull/1486 ?

[erikr]

@cooperlees Sounds suspiciously similar, and kudos to @keith's excellent choice of line-length, although 1) my issue was in context of Vim 8.1, not neovim, and 2) unsure if the exception he refers to is the same as what we're seeing here.

[ichard26]

Hello, yes the PR above is similar and probably could fix the problems, but
I think it will be better if I fix the source of the issue than putting a
workaround atop of a broken function like the PR above.

On Mon, Jun 15, 2020, 10:25 AM Erik Reinertsen [e-mail]
wrote:

@cooperlees https://github.com/cooperlees Sounds suspiciously similar,
and kudos to @keith https://github.com/keith's excellent choice of
line-length, although 1) my issue was in context of Vim 8.1, not neovim,
and 2) unsure if the exception he refers to is the same as what we're
seeing here.

—
You are receiving this because you were mentioned.
Reply to this email directly, view it on GitHub
https://github.com/psf/black/issues/1496#issuecomment-644167223, or
unsubscribe
https://github.com/notifications/unsubscribe-auth/APHZN7NIWMGIU6HHRSHHYI3RWYVMDANCNFSM4N5R7FGQ
.

[cooperlees]

Agree, but should we merge the workaround for now and have your upcoming PR remove it if no longer needed?

[ichard26]

If I don't get a PR ready in 40 minutes, go ahead on merge the workaround. You know what I was trying to do yesterday with pipenv 😂