color: add support for Windows consoles

Introduces color.mode configurable with values 'auto', 'ansi', or 'win32'.  Any
other value disables coloring.  When 'auto' is selected, the win32 console
method will be used if the win32console Python module is detected (requires
pywin32 to be installed).

hgext/color.py

@@ -61,6 +61,15 Default effects may be overridden from t
   resolve.resolved = green bold
 
   bookmarks.current = green
+
+The color extension will try to detect whether to use ANSI codes or
+Win32 console APIs, unless it is made explicit::
+
+  [color]
+  mode = ansi
+
+Any value other than 'ansi', 'win32', or 'auto' will disable color.
+
 '''
 
 import os, sys
@@ -150,19 +159,43 def popbuffer(orig, labeled=False):
         return ''.join(style(a, label) for a, label in _buffers.pop())
     return ''.join(a for a, label in _buffers.pop())
 
+mode = 'ansi'
 def write(orig, *args, **opts):
     label = opts.get('label', '')
     global _buffers
     if _buffers:
         _buffers[-1].extend([(str(a), label) for a in args])
+    elif mode == 'win32':
+        for a in args:
+            win32print(a, orig, **opts)
     else:
         return orig(*[style(str(a), label) for a in args], **opts)
 
 def write_err(orig, *args, **opts):
     label = opts.get('label', '')
+    if mode == 'win32':
+        for a in args:
+            win32print(a, orig, **opts)
+    else:
     return orig(*[style(str(a), label) for a in args], **opts)
 
 def uisetup(ui):
+    global mode
+    mode = ui.config('color', 'mode', 'auto')
+    if mode == 'auto':
+        if os.name == 'nt' and 'TERM' not in os.environ:
+            # looks line a cmd.exe console, use win32 API or nothing
+            mode = w32effects and 'win32' or 'none'
+        else:
+            mode = 'ansi'
+    if mode == 'win32':
+        if w32effects is None:
+            # only warn if color.mode is explicitly set to win32
+            ui.warn(_('win32console not found, please install pywin32\n'))
+            return
+        _effects.update(w32effects)
+    elif mode != 'ansi':
+        return
     def colorcmd(orig, ui_, opts, cmd, cmdfunc):
         if (opts['color'] == 'always' or
             (opts['color'] == 'auto' and (os.environ.get('TERM') != 'dumb'
@@ -180,3 +213,64 def uisetup(ui):
 
 commands.globalopts.append(('', 'color', 'auto',
                             _("when to colorize (always, auto, or never)")))
+
+try:
+    import re
+    from win32console import *
+
+    # http://msdn.microsoft.com/en-us/library/ms682088%28VS.85%29.aspx
+    w32effects = {
+        'none': 0,
+        'black': 0,
+        'red': FOREGROUND_RED,
+        'green': FOREGROUND_GREEN,
+        'yellow': FOREGROUND_RED | FOREGROUND_GREEN,
+        'blue': FOREGROUND_BLUE,
+        'magenta': FOREGROUND_BLUE | FOREGROUND_RED,
+        'cyan': FOREGROUND_BLUE | FOREGROUND_GREEN,
+        'white': FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE,
+        'bold': FOREGROUND_INTENSITY,
+        'black_background': 0,
+        'red_background': BACKGROUND_RED,
+        'green_background': BACKGROUND_GREEN,
+        'blue_background': BACKGROUND_BLUE,
+        'cyan_background': BACKGROUND_BLUE | BACKGROUND_GREEN,
+        'bold_background': FOREGROUND_INTENSITY,
+        'underline': COMMON_LVB_UNDERSCORE,     # double-byte charsets only
+        'inverse': COMMON_LVB_REVERSE_VIDEO,    # double-byte charsets only
+    }
+
+    stdout = GetStdHandle(STD_OUTPUT_HANDLE)
+    origattr = stdout.GetConsoleScreenBufferInfo()['Attributes']
+    ansire = re.compile('\033\[([^m]*)m([^\033]*)(.*)', re.MULTILINE | re.DOTALL)
+
+    def win32print(text, orig, **opts):
+        label = opts.get('label', '')
+        attr = 0
+
+        # determine console attributes based on labels
+        for l in label.split():
+            style = _styles.get(l, '')
+            for effect in style.split():
+                attr |= w32effects[effect]
+
+        # hack to ensure regexp finds data
+        if not text.startswith('\033['):
+            text = '\033[m' + text
+
+        # Look for ANSI-like codes embedded in text
+        m = re.match(ansire, text)
+        while m:
+            for sattr in m.group(1).split(';'):
+                if sattr:
+                    val = int(sattr)
+                    attr = val and attr|val or 0
+            stdout.SetConsoleTextAttribute(attr or origattr)
+            orig(m.group(2), **opts)
+            m = re.match(ansire, m.group(3))
+
+        # Explicity reset original attributes
+        stdout.SetConsoleTextAttribute(origattr)
+
+except ImportError:
+    w32effects = None