"""
This module contains components that specifically address the styling and theming
of the ``--help`` output.
"""
import dataclasses
import dataclasses as dc
import sys
from collections.abc import Callable
from dataclasses import dataclass
import click
if sys.version_info >= (3, 11):
from typing import Self
else:
from typing_extensions import Self
from cloup._util import FrozenSpace, identity
from cloup.typing import MISSING, Possibly
IStyle = Callable[[str], str]
"""A callable that takes a string and returns a styled version of it."""
@dataclass(frozen=True)
class HelpTheme:
"""A collection of styles for several elements of the help page.
A "style" is just a function or a callable that takes a string and returns
a styled version of it. This means you can use your favorite styling/color
library (like rich, colorful etc). Nonetheless, given that Click has some
basic styling functionality built-in, Cloup provides the :class:`Style`
class, which is a wrapper of the ``click.style`` function.
:param invoked_command:
Style of the invoked command name (in Usage).
:param command_help:
Style of the invoked command description (below Usage).
:param heading:
Style of help section headings.
:param constraint:
Style of an option group constraint description.
:param section_help:
Style of the help text of a section (the optional paragraph below the heading).
:param col1:
Style of the first column of a definition list (options and command names).
:param col2:
Style of the second column of a definition list (help text).
:param epilog:
Style of the epilog.
:param alias:
Style of subcommand aliases in a definition lists.
:param alias_secondary:
Style of separator and eventual parenthesis/brackets in subcommand alias lists.
If not provided, the ``alias`` style will be used.
"""
invoked_command: IStyle = identity
"""Style of the invoked command name (in Usage)."""
command_help: IStyle = identity
"""Style of the invoked command description (below Usage)."""
heading: IStyle = identity
"""Style of help section headings."""
constraint: IStyle = identity
"""Style of an option group constraint description."""
section_help: IStyle = identity
"""Style of the help text of a section (the optional paragraph below the heading)."""
col1: IStyle = identity
"""Style of the first column of a definition list (options and command names)."""
col2: IStyle = identity
"""Style of the second column of a definition list (help text)."""
alias: IStyle = identity
"""Style of subcommand aliases in a definition lists."""
alias_secondary: IStyle | None = None
"""Style of separator and eventual parenthesis/brackets in subcommand alias lists.
If not provided, the ``alias`` style will be used."""
epilog: IStyle = identity
"""Style of the epilog."""
def with_(
self,
invoked_command: IStyle | None = None,
command_help: IStyle | None = None,
heading: IStyle | None = None,
constraint: IStyle | None = None,
section_help: IStyle | None = None,
col1: IStyle | None = None,
col2: IStyle | None = None,
alias: IStyle | None = None,
alias_secondary: Possibly[IStyle | None] = MISSING,
epilog: IStyle | None = None,
**kwargs: object,
) -> Self:
"""Return a theme of the same type with the supplied fields replaced.
Additional keyword arguments are passed to :func:`dataclasses.replace`
to support fields added by subclasses.
"""
replacements = {key: val for key, val in locals().items() if val is not None}
if alias_secondary is MISSING:
del replacements["alias_secondary"]
replacements.pop("self")
replacements.pop("kwargs")
replacements.update(kwargs)
if replacements:
return dataclasses.replace(self, **replacements)
return self
@classmethod
def dark(cls) -> Self:
"""A theme assuming a dark terminal background color."""
return cls(
invoked_command=Style(fg="bright_yellow"),
heading=Style(fg="bright_white", bold=True),
constraint=Style(fg="magenta"),
col1=Style(fg="bright_yellow"),
alias=Style(fg="yellow"),
alias_secondary=Style(fg="white"),
)
@classmethod
def light(cls) -> Self:
"""A theme assuming a light terminal background color."""
return cls(
invoked_command=Style(fg="yellow"),
heading=Style(fg="bright_blue"),
constraint=Style(fg="red"),
col1=Style(fg="yellow"),
)
@dc.dataclass(frozen=True)
class Style:
"""Wraps :func:`click.style` for a better integration with :class:`HelpTheme`.
Available colors are defined as static constants in :class:`Color`.
Arguments are set to ``None`` by default. Passing ``False`` to boolean args
or ``Color.reset`` as color causes a reset code to be inserted.
With respect to :func:`click.style`, this class:
- has an argument less, ``reset``, which is always ``True``
- add the ``text_transform``.
.. warning::
The arguments ``overline``, ``italic`` and ``strikethrough`` are only
supported in Click 8 and will be ignored if you are using Click 7.
:param fg: foreground color
:param bg: background color
:param bold:
:param dim:
:param underline:
:param overline:
:param italic:
:param blink:
:param reverse:
:param strikethrough:
:param text_transform:
a generic string transformation; useful to apply functions like ``str.upper``
.. versionadded:: 0.8.0
"""
fg: int | tuple[int, int, int] | str | None = None
bg: int | tuple[int, int, int] | str | None = None
bold: bool | None = None
dim: bool | None = None
underline: bool | None = None
overline: bool | None = None
italic: bool | None = None
blink: bool | None = None
reverse: bool | None = None
strikethrough: bool | None = None
text_transform: IStyle | None = None
def __call__(self, text: str) -> str:
if self.text_transform:
text = self.text_transform(text)
return click.style(
text,
fg=self.fg,
bg=self.bg,
bold=self.bold,
dim=self.dim,
underline=self.underline,
overline=self.overline,
italic=self.italic,
blink=self.blink,
reverse=self.reverse,
strikethrough=self.strikethrough,
)
[docs]
class Color(FrozenSpace):
"""Colors accepted by :class:`Style` and :func:`click.style`."""
black = "black"
red = "red"
green = "green"
yellow = "yellow"
blue = "blue"
magenta = "magenta"
cyan = "cyan"
white = "white"
reset = "reset"
bright_black = "bright_black"
bright_red = "bright_red"
bright_green = "bright_green"
bright_yellow = "bright_yellow"
bright_blue = "bright_blue"
bright_magenta = "bright_magenta"
bright_cyan = "bright_cyan"
bright_white = "bright_white"
DEFAULT_THEME = HelpTheme()