Black fails to parse match-case statement in black/scripts/generate_schema.py

[dankrzeminski32]

Describe the bug

I found this bug while trying to run black on it's own source code.

The file generate_schema.py in the scripts folder failed to get parsed properly.

To Reproduce

This is the function that causes the issue,

def generate_schema_from_click(
    cmd: click.Command,
) -> dict[str, Any]:
    result: dict[str, dict[str, Any]] = {}
    for param in cmd.params:
        if not isinstance(param, click.Option) or param.is_eager:
            continue

        assert param.name
        name = param.name.replace("_", "-")

        result[name] = {}

        match param.type:
            case click.types.IntParamType():
                result[name]["type"] = "integer"
            case click.types.StringParamType() | click.types.Path():
                result[name]["type"] = "string"
            case click.types.Choice(choices=choices):
                result[name]["enum"] = choices
            case click.types.BoolParamType():
                result[name]["type"] = "boolean"
            case _:
                msg = f"{param.type!r} not a known type for {param}"
                raise TypeError(msg)

        if param.multiple:
            result[name] = {"type": "array", "items": result[name]}

        result[name]["description"] = param.help

        if param.default is not None and not param.multiple:
            result[name]["default"] = param.default

    return result

it is found in black's source code under scripts/generate_schema.py, you can run black on that file:

$ black scripts/generate_schema.py

The resulting error is:

error: cannot format scripts/generate_schema.py: Cannot parse: 22:14: match param.type:

Oh no! 💥 💔 💥
1 file failed to reformat.

Expected behavior

black parses the file correctly and potentially formats the code.

Environment

• Black's version: 24.2.0 (compiled: yes)
• OS and Python version: macOS, python 3.11.3

[hauntsaninja]

Yeah, I noticed this the other day. I think it's just a target version issue (see also #3294 )

[dankrzeminski32]

Thanks, that makes sense. It worked when i used:

black scripts/generate_schema.py -t py310