This module handles terminal interaction including ANSI color codes.
"""
+import os
+import sys
+
+# Selection of when we want our output to be colored
+COLOR_IF_TERMINAL, COLOR_ALWAYS, COLOR_NEVER = range(3)
+
class Color(object):
"""Conditionally wraps text in ANSI color escape sequences."""
BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE = range(8)
BOLD = -1
- COLOR_START = '\033[1;%dm'
+ BRIGHT_START = '\033[1;%dm'
+ NORMAL_START = '\033[22;%dm'
BOLD_START = '\033[1m'
RESET = '\033[0m'
- def __init__(self, enabled=True):
+ def __init__(self, colored=COLOR_IF_TERMINAL):
"""Create a new Color object, optionally disabling color output.
Args:
enabled: True if color output should be enabled. If False then this
class will not add color codes at all.
"""
- self._enabled = enabled
+ self._enabled = (colored == COLOR_ALWAYS or
+ (colored == COLOR_IF_TERMINAL and os.isatty(sys.stdout.fileno())))
- def Start(self, color):
+ def Start(self, color, bright=True):
"""Returns a start color code.
Args:
otherwise returns empty string
"""
if self._enabled:
- return self.COLOR_START % (color + 30)
+ base = self.BRIGHT_START if bright else self.NORMAL_START
+ return base % (color + 30)
return ''
def Stop(self):
returns empty string
"""
if self._enabled:
- return self.RESET
+ return self.RESET
return ''
- def Color(self, color, text):
+ def Color(self, color, text, bright=True):
"""Returns text with conditionally added color escape sequences.
Keyword arguments:
returns text with color escape sequences based on the value of color.
"""
if not self._enabled:
- return text
+ return text
if color == self.BOLD:
- start = self.BOLD_START
+ start = self.BOLD_START
else:
- start = self.COLOR_START % (color + 30)
+ base = self.BRIGHT_START if bright else self.NORMAL_START
+ start = base % (color + 30)
return start + text + self.RESET