core (constants), tools (common/ansi): moved ANSI escape codes to a dedicated class, with helper methods

src/tools/common/ansi.py

@@ -0,0 +1,49 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+
+# SàT: a XMPP client
+# Copyright (C) 2009-2016 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import sys
+
+class ANSI(object):
+
+    ## ANSI escape sequences ##
+    RESET = '\033[0m'
+    NORMAL_WEIGHT = '\033[22m'
+    FG_BLACK, FG_RED, FG_GREEN, FG_YELLOW, FG_BLUE, FG_MAGENTA, FG_CYAN, FG_WHITE = ('\033[3%dm' % nb for nb in xrange(8))
+    BOLD = '\033[1m'
+    BLINK = '\033[5m'
+    BLINK_OFF = '\033[25m'
+
+    @classmethod
+    def color(cls, *args):
+        """output text using ANSI codes
+
+        this method simply merge arguments, and add RESET if is not the last arguments
+        """
+        # XXX: we expect to have at least on argument
+        if args[-1] != cls.RESET:
+            args = list(args)
+            args.append(cls.RESET)
+        return u''.join(args)
+
+
+if not sys.stdout.isatty():
+    # we don't want ANSI escape codes if we are not outputing to a tty!
+    for attr in dir(ANSI):
+        if isinstance(getattr(ANSI, attr), basestring):
+            setattr(ANSI, attr, u'')