New option --color to control the coloring, and split the coloring from the output synchronization code

waflib/Logs.py

@@ -7,51 +7,18 @@ logging, colors, terminal width and pretty-print
 """
 
 import os, re, traceback, sys
+from waflib import ansiterm
 
-_nocolor = os.environ.get('NOCOLOR', 'no') not in ('no', '0', 'false')
-try:
-	if not _nocolor:
-		import waflib.ansiterm
-except ImportError:
-	pass
+if not os.environ.get('NOSYNC', False):
+	# synchronized output is nearly mandatory to prevent garbled output
+	if sys.stdout.isatty() and id(sys.stdout) == id(sys.__stdout__):
+		sys.stdout = ansiterm.AnsiTerm(sys.stdout)
+		os.environ['TERM'] = 'vt100' # <- not sure about this
+	if sys.stderr.isatty() and id(sys.stderr) == id(sys.__stderr__):
+		sys.stderr = ansiterm.AnsiTerm(sys.stderr)
+		os.environ['TERM'] = 'vt100' # <- not sure about this
 
-try:
-	import threading
-except ImportError:
-	if not 'JOBS' in os.environ:
-		# no threading :-(
-		os.environ['JOBS'] = '1'
-else:
-	wlock = threading.Lock()
-
-	class sync_stream(object):
-		def __init__(self, stream):
-			self.stream = stream
-			self.encoding = self.stream.encoding
-
-		def write(self, txt):
-			try:
-				wlock.acquire()
-				self.stream.write(txt)
-				self.stream.flush()
-			finally:
-				wlock.release()
-
-		def fileno(self):
-			return self.stream.fileno()
-
-		def flush(self):
-			self.stream.flush()
-
-		def isatty(self):
-			return self.stream.isatty()
-
-	if not os.environ.get('NOSYNC', False):
-		if id(sys.stdout) == id(sys.__stdout__):
-			sys.stdout = sync_stream(sys.stdout)
-			sys.stderr = sync_stream(sys.stderr)
-
-import logging # import other modules only after
+import logging # the logging module keeps holds reference on sys.stderr
 
 LOG_FORMAT = "%(asctime)s %(c1)s%(zone)s%(c2)s %(message)s"
 HOUR_FORMAT = "%H:%M:%S"
@@ -73,15 +40,17 @@ colors_lst = {
 'cursor_off' :'\x1b[?25l',
 }
 
-got_tty = not os.environ.get('TERM', 'dumb') in ['dumb', 'emacs']
-if got_tty:
-	try:
-		got_tty = sys.stderr.isatty() and sys.stdout.isatty()
-	except AttributeError:
-		got_tty = False
-
-if (not got_tty and os.environ.get('TERM', 'dumb') != 'msys') or _nocolor:
-	colors_lst['USE'] = False
+def enable_colors(level):
+	if level == 0:
+		colors_lst['USE'] = False
+	elif level == 1:
+		# and here we guess
+		term = os.environ.get('TERM', '')
+		if term in ['dumb', 'emacs']:
+			colors_lst['USE'] = False
+		pass
+	else:
+		colors_lst['USE'] = True
 
 def get_term_cols():
 	return 80

waflib/Options.py

@@ -14,6 +14,13 @@ as well as custom ones, used by the ``options`` wscript function.
 import os, tempfile, optparse, sys, re
 from waflib import Logs, Utils, Context
 
+try:
+	import threading
+except ImportError:
+	if not 'JOBS' in os.environ:
+		# no threading :-(
+		os.environ['JOBS'] = '1'
+
 cmds = 'distclean configure build install clean uninstall check dist distcheck'.split()
 """
 Constant representing the default waf commands displayed in::
@@ -51,6 +58,7 @@ class opt_parser(optparse.OptionParser):
 		self.ctx = ctx
 
 		jobs = ctx.jobs()
+		p('-c', '--color',    dest='colors',  default='auto', action='store', help='whether to use colors (always/auto/never) [default: auto]')
 		p('-j', '--jobs',     dest='jobs',    default=jobs, type='int', help='amount of parallel jobs (%r)' % jobs)
 		p('-k', '--keep',     dest='keep',    default=0,     action='count', help='keep running happily even if errors are found')
 		p('-v', '--verbose',  dest='verbose', default=0,     action='count', help='verbosity level -v -vv or -vvv [default: 0]')
@@ -242,6 +250,15 @@ class OptionsContext(Context.Context):
 		if options.verbose >= 1:
 			self.load('errcheck')
 
+		try:
+			colors = {'always' : 2, 'auto' : 1, 'never' : 0}[options.colors]
+		except KeyError:
+			self.parser.error('Bad option "%s" for --color option' % options.colors)
+		else:
+			if os.environ.get('NOCOLOR', ''):
+				colors = 0
+			Logs.enable_colors(colors)
+
 	def execute(self):
 		"""
 		See :py:func:`waflib.Context.Context.execute`

waflib/ansiterm.py

@@ -11,12 +11,35 @@ console commands.
 
 """
 
-import sys, os, re, threading
+import re
+from waflib.Utils import threading
+
+wlock = threading.Lock()
 
 try:
 	from ctypes import Structure, windll, c_short, c_ulong, c_int, byref, c_wchar
 except ImportError:
-	pass
+	class AnsiTerm(object):
+		def __init__(self, stream):
+			self.stream = stream
+			self.encoding = self.stream.encoding
+
+		def write(self, txt):
+			try:
+				wlock.acquire()
+				self.stream.write(txt)
+				self.stream.flush()
+			finally:
+				wlock.release()
+
+		def fileno(self):
+			return self.stream.fileno()
+
+		def flush(self):
+			self.stream.flush()
+
+		def isatty(self):
+			return self.stream.isatty()
 else:
 
 	class COORD(Structure):
@@ -37,7 +60,6 @@ else:
 		_type = str
 
 	to_int = lambda number, default: number and int(number) or default
-	wlock = threading.Lock()
 
 	STD_OUTPUT_HANDLE = -11
 	STD_ERROR_HANDLE = -12
@@ -230,6 +252,8 @@ else:
 						else:
 							self.writeconsole(txt)
 				else:
+					# no support for colors in the console, just output the text:
+					# eclipse or msys may be able to interpret the escape sequences
 					self.stream.write(text)
 			finally:
 				wlock.release()
@@ -265,8 +289,4 @@ else:
 		def isatty(self):
 			return self._isatty
 
-	if sys.stdout.isatty() or sys.stderr.isatty():
-		sys.stderr = AnsiTerm(sys.stderr)
-		sys.stdout = AnsiTerm(sys.stdout)
-		os.environ['TERM'] = 'vt100'