color.py

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# Copyright (c) 2015, Bielefeld University
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from __future__ import print_function
import sys

# bold colors
_ansi = {'red': 91, 'yellow': 93}


def is_tty(stream):  # taken from catkin_tools/common.py
    """Returns True if the given stream is a tty, else False"""
    return hasattr(stream, 'isatty') and stream.isatty()


def colorize(msg, color, file=sys.stderr, alt_text=None):
    try:
        color = _ansi[color]
    except KeyError:
        pass

    if color and is_tty(file):
        return '\033[%dm%s\033[0m' % (color, msg)
    elif alt_text:
        return '%s%s' % (alt_text, msg)
    else:
        return msg


def message(msg, *args, **kwargs):
    file = kwargs.get('file', sys.stderr)
    alt_text = kwargs.get('alt_text', None)
    color = kwargs.get('color', None)
    print(colorize(msg, color, file, alt_text), *args, file=file)


def warning(*args, **kwargs):
    defaults = dict(file=sys.stderr, alt_text='warning: ', color='yellow')
    defaults.update(kwargs)
    message(*args, **defaults)


def error(*args, **kwargs):
    defaults = dict(file=sys.stderr, alt_text='error: ', color='red')
    defaults.update(kwargs)
    message(*args, **defaults)