Function _detect_program_name

src/click/utils.py:549–601

Determine the command used to run the program, for use in help text. If a file or entry point was executed, the file name is returned. If ``python -m`` was used to execute a module or package, ``python -m name`` is returned. This doesn't try to be too precise, the goal is to give a

(
    path: str | None = None, _main: ModuleType | None = None
)

def _detect_program_name(
    path: str | None = None, _main: ModuleType | None = None
) -> str:
    """Determine the command used to run the program, for use in help
    text. If a file or entry point was executed, the file name is
    returned. If ``python -m`` was used to execute a module or package,
    ``python -m name`` is returned.

    This doesn't try to be too precise, the goal is to give a concise
    name for help text. Files are only shown as their name without the
    path. ``python`` is only shown for modules, and the full path to
    ``sys.executable`` is not shown.

    :param path: The Python file being executed. Python puts this in
        ``sys.argv[0]``, which is used by default.
    :param _main: The ``__main__`` module. This should only be passed
        during internal testing.

    .. versionadded:: 8.0
        Based on command args detection in the Werkzeug reloader.

    :meta private:
    """
    if _main is None:
        _main = sys.modules["__main__"]

    if not path:
        path = sys.argv[0]

    # The value of __package__ indicates how Python was called. It may
    # not exist if a setuptools script is installed as an egg. It may be
    # set incorrectly for entry points created with pip on Windows.
    # It is set to "" inside a Shiv or PEX zipapp.
    if getattr(_main, "__package__", None) in {None, ""} or (
        os.name == "nt"
        and _main.__package__ == ""
        and not os.path.exists(path)
        and os.path.exists(f"{path}.exe")
    ):
        # Executed a file, like "python app.py".
        return os.path.basename(path)

    # Executed a module, like "python -m example".
    # Rewritten by Python from "-m script" to "/path/to/script.py".
    # Need to look at main module to determine how it was executed.
    py_module = t.cast(str, _main.__package__)
    name = os.path.splitext(os.path.basename(path))[0]

    # A submodule like "example.cli".
    if name != "__main__":
        py_module = f"{py_module}.{name}"

    return f"python -m {py_module.lstrip('.')}"


def _expand_args(