enumchoice

enumchoice is a small helper for Click CLIs that lets a Python Enum be used directly as an option type. It exposes enum member names as the accepted command-line choices and returns the matching enum member to the Click command.

Why it exists

Click's built-in click.Choice validates strings. If an option represents an Enum, a command normally has to build a list of enum names for Click and then convert the selected strings back to enum members. EnumChoice keeps those two steps in one Click parameter type.

Installation

pip install enumchoice

The package requires Python 3.8 or newer and Click 7.0 or newer.

Usage

from enum import Enum

import click
from enumchoice import EnumChoice


class Color(Enum):
    red = "r"
    blue = "b"
    green = "g"


@click.command()
@click.option("--color", type=EnumChoice(Color), default=Color.red, show_default=True)
def cli(color):
    assert isinstance(color, Color)
    click.echo(color.name)

Matching is case-insensitive by default, so --color RED, --color red, and --color ReD all resolve to Color.red. Pass case_sensitive=True to require exact enum member names.

EnumChoice also works with Click's multiple=True options:

@click.option(
    "--color",
    multiple=True,
    default=list(Color),
    type=EnumChoice(Color),
)
def cli(color):
    # color is a tuple of Color members.
    ...

How it works

EnumChoice subclasses click.Choice. Its constructor builds the choice list from each enum member's name. During conversion it lets Click perform normal choice validation and case normalization, then looks up the normalized name in the enum class and returns that member.

None and already-converted Enum instances pass through unchanged, which allows enum-valued defaults such as default=Color.red or default=list(Color).

Behavior and limitations

• Choices are enum member names, not enum values.
• Click callbacks receive enum members, not strings.
• No aliases are added beyond the enum's declared member names.
• The package metadata currently marks the project as pre-alpha, version 0.0.1.

Development

pip install -r requirements_dev.txt
pip install -e .
make test
make lint
make docs

The repository includes pytest, pre-commit, coverage, Sphinx documentation, and release packaging configuration. The project is distributed under the MIT license.

Changelog

0.0.1

• First release on PyPI.