Incompatible with black-22.10.1.dev19+gffaaf48 and later

[akaihola]

Describe the bug
Unit tests fail if psf/black@ffaaf48 or later is installed.

To Reproduce
Steps to reproduce the behavior:

1. In a fresh virtualenv, pip install 'darker[test]==1.5.1' git+https://github.com/psf/black.git@ffaaf48
2. In a Git working tree of a Python repository, run Darker with darker
3. See error

Expected behavior
Darker should run successfully and reformat modified regions of Python fules.

Screenshots

Traceback (most recent call last):
  File "bin/darker", line 8, in <module>
    sys.exit(main_with_error_handling())
  File "darker/__main__.py", line 486, in main_with_error_handling
    return main()
  File "darker/__main__.py", line 423, in main
    files_to_process = filter_python_files(paths, root, {})
  File "darker/black_diff.py", line 142, in filter_python_files
    gen_python_files(
TypeError: gen_python_files() got an unexpected keyword argument 'gitignore'

Environment (please complete the following information):

• OS: NixOS 22.05
• Python version: 3.9.13
• Git version: 2.36.2
• Darker version: 1.5.1
• Black version: commit ffaaf48

Additional context
psf/black@ffaaf48 replaces the gitignore: Optional[PathSpec] argument of black.files.gen_python_files() with gitignore_dict: Optional[Dict[Path, PathSpec]].

Before that commit, gitignore is used like:

        # First ignore files matching .gitignore, if passed
        if gitignore is not None and gitignore.match_file(normalized_path):
            report.path_ignored(child, "matches the .gitignore file content")
            continue

And after the commit, gitignore_dict like:

        # First ignore files matching .gitignore, if passed
        if gitignore_dict and path_is_ignored(child, gitignore_dict, report):
            continue

# [...]

        if child.is_dir():
            # If gitignore is None, gitignore usage is disabled, while a Falsey
            # gitignore is when the directory doesn't have a .gitignore file.
            if gitignore_dict is not None:
                new_gitignore_dict = {
                    **gitignore_dict,
                    root / child: get_gitignore(child),
                }
            else:
                new_gitignore_dict = None

# [then passing `new_gitignore_dict` back to the same function

[soxofaan]

Any chance on a darker release in near future including fix for this issue?
I'm running darker in GitHub Action through pre-commit, and now I have to manually pin down black<22.12.0 to keep that working

(thanks for darker by the way, great tool, I use it all the time)

[soxofaan]

An out-of-the-box pipx install of darker is also broken at the moment.

Workaround is to use pipx inject to downgrade black:

pipx inject darker 'black<22.12.0'

[akaihola]

@soxofaan, thanks for appreciation! Darker 1.6.0 with a fix for this has now been released.