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| -rw-r--r-- | lib/spack/spack/color.py | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/lib/spack/spack/color.py b/lib/spack/spack/color.py new file mode 100644 index 0000000000..f84ba626c3 --- /dev/null +++ b/lib/spack/spack/color.py @@ -0,0 +1,162 @@ +""" +This file implements an expression syntax, similar to printf, for adding +ANSI colors to text. + +See colorize(), cwrite(), and cprint() for routines that can generate +colored output. + +colorize will take a string and replace all color expressions with +ANSI control codes. If the isatty keyword arg is set to False, then +the color expressions will be converted to null strings, and the +returned string will have no color. + +cwrite and cprint are equivalent to write() and print() calls in +python, but they colorize their output. If the stream argument is +not supplied, they write to sys.stdout. + +Here are some example color expressions: + + @r Turn on red coloring + @R Turn on bright red coloring + @*b Turn on bold, blue text + @_B Turn on bright blue text with an underline + @. Revert to plain formatting + @*g{green} Print out 'green' in bold, green text, then reset to plain. + @*ggreen@. Print out 'green' in bold, green text, then reset to plain. + +The syntax consists of: + + color-expr = '@' [style] color-code '{' text '}' | '@.' | '@@' + style = '*' | '_' + color-code = [krgybmcwKRGYBMCW] + text = .* + +'@' indicates the start of a color expression. It can be followed +by an optional * or _ that indicates whether the font should be bold or +underlined. If * or _ is not provided, the text will be plain. Then +an optional color code is supplied. This can be [krgybmcw] or [KRGYBMCW], +where the letters map to black(k), red(r), green(g), yellow(y), blue(b), +magenta(m), cyan(c), and white(w). Lowercase letters denote normal ANSI +colors and capital letters denote bright ANSI colors. + +Finally, the color expression can be followed by text enclosed in {}. If +braces are present, only the text in braces is colored. If the braces are +NOT present, then just the control codes to enable the color will be output. +The console can be reset later to plain text with '@.'. + +To output an @, use '@@'. To output a } inside braces, use '}}'. +""" +import re +import sys +import spack.error + +class ColorParseError(spack.error.SpackError): + """Raised when a color format fails to parse.""" + def __init__(self, message): + super(ColorParseError, self).__init__(message) + +# Text styles for ansi codes +styles = {'*' : '1;%s', # bold + '_' : '4:%s', # underline + None : '0;%s' } # plain + +# Dim and bright ansi colors +colors = {'k' : 30, 'K' : 90, # black + 'r' : 31, 'R' : 91, # red + 'g' : 32, 'G' : 92, # green + 'y' : 33, 'Y' : 93, # yellow + 'b' : 34, 'B' : 94, # blue + 'm' : 35, 'M' : 95, # magenta + 'c' : 36, 'C' : 96, # cyan + 'w' : 37, 'W' : 97 } # white + +# Regex to be used for color formatting +color_re = r'@(?:@|\.|([*_])?([a-zA-Z])?(?:{((?:[^}]|}})*)})?)' + + +class match_to_ansi(object): + def __init__(self, color=True): + self.color = color + + def escape(self, s): + """Returns a TTY escape sequence for a color""" + if self.color: + return "\033[%sm" % s + else: + return '' + + def __call__(self, match): + """Convert a match object generated by color_re into an ansi color code + This can be used as a handler in re.sub. + """ + style, color, text = match.groups() + m = match.group(0) + + if m == '@@': + return '@' + elif m == '@.': + return self.escape(0) + elif m == '@' or (style and not color): + raise ColorParseError("Incomplete color format: '%s'" % m) + elif color not in colors: + raise ColorParseError("invalid color specifier: '%s'" % color) + + colored_text = '' + if text: + colored_text = text + self.escape(0) + + if style == '*': + color_code = self.escape(styles[style] % colors[color]) + elif style == '_': + color_code = self.escape(styles[style] % colors[color]) + else: + color_code = self.escape(styles[style] % colors[color]) + + return color_code + colored_text + + +def colorize(string, **kwargs): + """Take a string and replace all color expressions with ANSI control + codes. Return the resulting string. + If color=False is supplied, output will be plain text without + control codes, for output to non-console devices. + """ + color = kwargs.get('color', True) + return re.sub(color_re, match_to_ansi(color), string) + + +def cwrite(string, stream=sys.stdout, color=None): + """Replace all color expressions in string with ANSI control + codes and write the result to the stream. If color is + False, this will write plain text with o color. If True, + then it will always write colored output. If not supplied, + then it will be set based on stream.isatty(). + """ + if color == None: + color = stream.isatty() + stream.write(colorize(string, color=color)) + + +def cprint(string, stream=sys.stdout, color=None): + """Same as cwrite, but writes a trailing newline to the stream.""" + cwrite(string + "\n", stream, color) + + +class ColorStream(object): + def __init__(self, stream, color=None): + self.__class__ = type(stream.__class__.__name__, + (self.__class__, stream.__class__), {}) + self.__dict__ = stream.__dict__ + self.color = color + self.stream = stream + + def write(self, string, **kwargs): + if kwargs.get('raw', False): + super(ColorStream, self).write(string) + else: + cwrite(string, self.stream, self.color) + + def writelines(self, sequence, **kwargs): + raw = kwargs.get('raw', False) + for string in sequence: + self.write(string, self.color, raw=raw) |