Naming decorator

naming_decorator.py

from functools import wraps

class InvalidCase(Exception):
    """The case chose is not valid."""

VALID_CASES = ['title', 'lower', 'upper']

def apply_convention(function_argument=None, *, case='title', separator='-'):
    if case not in VALID_CASES:
        raise InvalidCase(f'Case {case} is not valid, please choose one of {VALID_CASES}.')
    def decorate(function):
        @wraps(function)
        def wrap(*args, **kwargs):
            items = function(*args, **kwargs)
            return separator.join([getattr(item, case)() for item in items])
        return wrap
    if function_argument:
        return decorate(function_argument)
    return decorate


@apply_convention
def name():
    return ['tes', 'bla', 'sdf']

@apply_convention(separator='.')
def name2():
    return ['tes', 'bla', 'sdf']

@apply_convention(case='lower')
def name3():
    return ['tes', 'bla', 'sdf']

@apply_convention(case='upper', separator='/')
def name4():
    return ['tes', 'bla', 'sdf']


if __name__ == '__main__':
    print(name())
    print(name2())
    print(name3())
    print(name4())


# ❯ python naming.py
# Tes-Bla-Sdf
# Tes.Bla.Sdf
# tes-bla-sdf
# TES/BLA/SDF