BLACK-ISORT linter fails on Windows when black==24.1.1 and Python==3.9

[justinchuby]

This linter processes the file with isort before sending the result to black as input to the subprocess.

In

lintrunner-adapters/lintrunner_adapters/adapters/black_isort_linter.py

Lines 42 to 58 in c9727c9

	proc = run_command(
	[
	sys.executable,
	"-mblack",
	*(("--pyi",) if filename.endswith(".pyi") else ()),
	*(("--ipynb",) if filename.endswith(".ipynb") else ()),
	*(("--fast",) if fast else ()),
	"--stdin-filename",
	filename,
	"-",
	],
	stdin=None,
	input=import_sorted,
	retries=retries,
	timeout=timeout,
	check=True,
	)

, the input argument was somehow not taken by black when black==24.1.1 on Windows, Python 3.8/Python 3.9.

Maybe consider pipeline the results instead and send it via stdin?

[guotuofeng]

do we try stdin?

[justinchuby]

It is still failing even after switching to stdin. I am not sure what is going on.

[justinchuby]

It has to be run within lintrunner, and python 3.9, and black==24.1.1, and Windows. Somehow the interaction among these tools and platforms caused the behavior. Does lintrunner set stdin on Windows the interfered with the tools? But only on Windows with Python 3.8/3.9?

[justinchuby]

I am trying to debug with black to make sure stdin is not empty when accepted by black, but I haven't been able to set breakpoints in black in my current environment. I am not sure which installation it was using.

[justinchuby]

I suspect black somehow failed to recognize there's stuff in stdin under certain conditions.

[guotuofeng]

psf/black#4209 is created.

[justinchuby]

Thanks for the investigation! Good catch that I didn’t actually look into the path files and forgot they were different.