diff options
Diffstat (limited to 'Lib/_colorize.py')
| -rw-r--r-- | Lib/_colorize.py | 255 |
1 files changed, 219 insertions, 36 deletions
diff --git a/Lib/_colorize.py b/Lib/_colorize.py index 54895488e74..4a310a40235 100644 --- a/Lib/_colorize.py +++ b/Lib/_colorize.py @@ -1,28 +1,17 @@ -from __future__ import annotations import io import os import sys +from collections.abc import Callable, Iterator, Mapping +from dataclasses import dataclass, field, Field + COLORIZE = True + # types if False: - from typing import IO, Literal - - type ColorTag = Literal[ - "PROMPT", - "KEYWORD", - "BUILTIN", - "COMMENT", - "STRING", - "NUMBER", - "OP", - "DEFINITION", - "SOFT_KEYWORD", - "RESET", - ] - - theme: dict[ColorTag, str] + from typing import IO, Self, ClassVar + _theme: Theme class ANSIColors: @@ -86,6 +75,186 @@ for attr, code in ANSIColors.__dict__.items(): setattr(NoColors, attr, "") +# +# Experimental theming support (see gh-133346) +# + +# - Create a theme by copying an existing `Theme` with one or more sections +# replaced, using `default_theme.copy_with()`; +# - create a theme section by copying an existing `ThemeSection` with one or +# more colors replaced, using for example `default_theme.syntax.copy_with()`; +# - create a theme from scratch by instantiating a `Theme` data class with +# the required sections (which are also dataclass instances). +# +# Then call `_colorize.set_theme(your_theme)` to set it. +# +# Put your theme configuration in $PYTHONSTARTUP for the interactive shell, +# or sitecustomize.py in your virtual environment or Python installation for +# other uses. Your applications can call `_colorize.set_theme()` too. +# +# Note that thanks to the dataclasses providing default values for all fields, +# creating a new theme or theme section from scratch is possible without +# specifying all keys. +# +# For example, here's a theme that makes punctuation and operators less prominent: +# +# try: +# from _colorize import set_theme, default_theme, Syntax, ANSIColors +# except ImportError: +# pass +# else: +# theme_with_dim_operators = default_theme.copy_with( +# syntax=Syntax(op=ANSIColors.INTENSE_BLACK), +# ) +# set_theme(theme_with_dim_operators) +# del set_theme, default_theme, Syntax, ANSIColors, theme_with_dim_operators +# +# Guarding the import ensures that your .pythonstartup file will still work in +# Python 3.13 and older. Deleting the variables ensures they don't remain in your +# interactive shell's global scope. + +class ThemeSection(Mapping[str, str]): + """A mixin/base class for theme sections. + + It enables dictionary access to a section, as well as implements convenience + methods. + """ + + # The two types below are just that: types to inform the type checker that the + # mixin will work in context of those fields existing + __dataclass_fields__: ClassVar[dict[str, Field[str]]] + _name_to_value: Callable[[str], str] + + def __post_init__(self) -> None: + name_to_value = {} + for color_name in self.__dataclass_fields__: + name_to_value[color_name] = getattr(self, color_name) + super().__setattr__('_name_to_value', name_to_value.__getitem__) + + def copy_with(self, **kwargs: str) -> Self: + color_state: dict[str, str] = {} + for color_name in self.__dataclass_fields__: + color_state[color_name] = getattr(self, color_name) + color_state.update(kwargs) + return type(self)(**color_state) + + @classmethod + def no_colors(cls) -> Self: + color_state: dict[str, str] = {} + for color_name in cls.__dataclass_fields__: + color_state[color_name] = "" + return cls(**color_state) + + def __getitem__(self, key: str) -> str: + return self._name_to_value(key) + + def __len__(self) -> int: + return len(self.__dataclass_fields__) + + def __iter__(self) -> Iterator[str]: + return iter(self.__dataclass_fields__) + + +@dataclass(frozen=True) +class Argparse(ThemeSection): + usage: str = ANSIColors.BOLD_BLUE + prog: str = ANSIColors.BOLD_MAGENTA + prog_extra: str = ANSIColors.MAGENTA + heading: str = ANSIColors.BOLD_BLUE + summary_long_option: str = ANSIColors.CYAN + summary_short_option: str = ANSIColors.GREEN + summary_label: str = ANSIColors.YELLOW + summary_action: str = ANSIColors.GREEN + long_option: str = ANSIColors.BOLD_CYAN + short_option: str = ANSIColors.BOLD_GREEN + label: str = ANSIColors.BOLD_YELLOW + action: str = ANSIColors.BOLD_GREEN + reset: str = ANSIColors.RESET + + +@dataclass(frozen=True) +class Syntax(ThemeSection): + prompt: str = ANSIColors.BOLD_MAGENTA + keyword: str = ANSIColors.BOLD_BLUE + builtin: str = ANSIColors.CYAN + comment: str = ANSIColors.RED + string: str = ANSIColors.GREEN + number: str = ANSIColors.YELLOW + op: str = ANSIColors.RESET + definition: str = ANSIColors.BOLD + soft_keyword: str = ANSIColors.BOLD_BLUE + reset: str = ANSIColors.RESET + + +@dataclass(frozen=True) +class Traceback(ThemeSection): + type: str = ANSIColors.BOLD_MAGENTA + message: str = ANSIColors.MAGENTA + filename: str = ANSIColors.MAGENTA + line_no: str = ANSIColors.MAGENTA + frame: str = ANSIColors.MAGENTA + error_highlight: str = ANSIColors.BOLD_RED + error_range: str = ANSIColors.RED + reset: str = ANSIColors.RESET + + +@dataclass(frozen=True) +class Unittest(ThemeSection): + passed: str = ANSIColors.GREEN + warn: str = ANSIColors.YELLOW + fail: str = ANSIColors.RED + fail_info: str = ANSIColors.BOLD_RED + reset: str = ANSIColors.RESET + + +@dataclass(frozen=True) +class Theme: + """A suite of themes for all sections of Python. + + When adding a new one, remember to also modify `copy_with` and `no_colors` + below. + """ + argparse: Argparse = field(default_factory=Argparse) + syntax: Syntax = field(default_factory=Syntax) + traceback: Traceback = field(default_factory=Traceback) + unittest: Unittest = field(default_factory=Unittest) + + def copy_with( + self, + *, + argparse: Argparse | None = None, + syntax: Syntax | None = None, + traceback: Traceback | None = None, + unittest: Unittest | None = None, + ) -> Self: + """Return a new Theme based on this instance with some sections replaced. + + Themes are immutable to protect against accidental modifications that + could lead to invalid terminal states. + """ + return type(self)( + argparse=argparse or self.argparse, + syntax=syntax or self.syntax, + traceback=traceback or self.traceback, + unittest=unittest or self.unittest, + ) + + @classmethod + def no_colors(cls) -> Self: + """Return a new Theme where colors in all sections are empty strings. + + This allows writing user code as if colors are always used. The color + fields will be ANSI color code strings when colorization is desired + and possible, and empty strings otherwise. + """ + return cls( + argparse=Argparse.no_colors(), + syntax=Syntax.no_colors(), + traceback=Traceback.no_colors(), + unittest=Unittest.no_colors(), + ) + + def get_colors( colorize: bool = False, *, file: IO[str] | IO[bytes] | None = None ) -> ANSIColors: @@ -138,26 +307,40 @@ def can_colorize(*, file: IO[str] | IO[bytes] | None = None) -> bool: return hasattr(file, "isatty") and file.isatty() -def set_theme(t: dict[ColorTag, str] | None = None) -> None: - global theme +default_theme = Theme() +theme_no_color = default_theme.no_colors() + + +def get_theme( + *, + tty_file: IO[str] | IO[bytes] | None = None, + force_color: bool = False, + force_no_color: bool = False, +) -> Theme: + """Returns the currently set theme, potentially in a zero-color variant. + + In cases where colorizing is not possible (see `can_colorize`), the returned + theme contains all empty strings in all color definitions. + See `Theme.no_colors()` for more information. + + It is recommended not to cache the result of this function for extended + periods of time because the user might influence theme selection by + the interactive shell, a debugger, or application-specific code. The + environment (including environment variable state and console configuration + on Windows) can also change in the course of the application life cycle. + """ + if force_color or (not force_no_color and can_colorize(file=tty_file)): + return _theme + return theme_no_color + + +def set_theme(t: Theme) -> None: + global _theme - if t: - theme = t - return + if not isinstance(t, Theme): + raise ValueError(f"Expected Theme object, found {t}") - colors = get_colors() - theme = { - "PROMPT": colors.BOLD_MAGENTA, - "KEYWORD": colors.BOLD_BLUE, - "BUILTIN": colors.CYAN, - "COMMENT": colors.RED, - "STRING": colors.GREEN, - "NUMBER": colors.YELLOW, - "OP": colors.RESET, - "DEFINITION": colors.BOLD, - "SOFT_KEYWORD": colors.BOLD_BLUE, - "RESET": colors.RESET, - } + _theme = t -set_theme() +set_theme(default_theme) |