Merge "add a global --color option"

color.py

@@ -83,12 +83,35 @@ def _Color(fg = None, bg = None, attr = None):
   return code
 
 
+DEFAULT = None
+
+def SetDefaultColoring(state):
+  """Set coloring behavior to |state|.
+
+  This is useful for overriding config options via the command line.
+  """
+  if state is None:
+    # Leave it alone -- return quick!
+    return
+
+  global DEFAULT
+  state = state.lower()
+  if state in ('auto',):
+    DEFAULT = state
+  elif state in ('always', 'yes', 'true', True):
+    DEFAULT = 'always'
+  elif state in ('never', 'no', 'false', False):
+    DEFAULT = 'never'
+
+
 class Coloring(object):
   def __init__(self, config, section_type):
     self._section = 'color.%s' % section_type
     self._config = config
     self._out = sys.stdout
 
+    on = DEFAULT
+    if on is None:
       on = self._config.GetString(self._section)
       if on is None:
         on = self._config.GetString('color.ui')

main.py

@@ -36,6 +36,7 @@ try:
 except ImportError:
   kerberos = None
 
+from color import SetDefaultColoring
 from trace import SetTrace
 from git_command import git, GitCommand
 from git_config import init_ssh, close_ssh
@@ -69,6 +70,9 @@ global_options.add_option('-p', '--paginate',
 global_options.add_option('--no-pager',
                           dest='no_pager', action='store_true',
                           help='disable the pager')
+global_options.add_option('--color',
+                          choices=('auto', 'always', 'never'), default=None,
+                          help='control color usage: auto, always, never')
 global_options.add_option('--trace',
                           dest='trace', action='store_true',
                           help='trace git command execution')
@@ -113,6 +117,8 @@ class _Repo(object):
         print('fatal: invalid usage of --version', file=sys.stderr)
         return 1
 
+    SetDefaultColoring(gopts.color)
+
     try:
       cmd = self.commands[name]
     except KeyError: