"not equivalent to the source" error

[ivirshup]

Describe the bug A clear and concise description of what the bug is.

Black errors while checking a file.

To Reproduce Steps to reproduce the behavior:

1. Take this file
2. Run Black on it with these arguments --check --diff
3. See error

error: cannot format scanpy/metrics/_gearys_c.py: INTERNAL ERROR: Black produced code that is not equivalent to the source.  Please report a bug on https://github.com/psf/black/issues.  This diff might be helpful: /var/folders/bd/43q20k0n6z15tdfzxvd22r7c0000gn/T/blk_ag2u14jv.log
Oh no! 💥 💔 💥
1 file would fail to reformat.

• Version: master and release
• OS and Python version: macOS for master and release, version black-19.10b0 on travis (failed build). Python 3.7 all around.

Does this bug also happen on master?

Yup. Not using the online formatter, but I installed it locally (macOS) and it failed

Additional context

Log contents (gist)

[JelleZijlstra]

This looks like the same tabs/spaces issue that caused #1170.

[ivirshup]

Update: If I remove the # fmt: off comment on line 102 the error stops occurring.

[ivirshup]

Just came back to say I was getting this issue with black==20.8b1. However, I closed the # fmt: off with a # fmt: on and now it works.

[ichard26]

@ivirshup good to know! In that case, I'll close this issue as another case of GH-569.