Bug 915508 - Change the order of space and comma in the mach status line when several directories are built at the same time; r=gps

python/mozbuild/mozbuild/mach_commands.py

@@ -4,6 +4,7 @@
 
 from __future__ import print_function, unicode_literals
 
+import itertools
 import logging
 import operator
 import os
@@ -160,11 +161,12 @@ class BuildProgressFooter(object):
                     ' ',
                     '(',
                 ])
-                for d in active_dirs:
-                    parts.extend([
-                        ('magenta', d), ' ,'
-                    ])
-                parts[-1] = ')'
+                if active_dirs:
+                    commas = [', '] * (len(active_dirs) - 1)
+                    magenta_dirs = [('magenta', d) for d in active_dirs]
+                    parts.extend(i.next() for i in itertools.cycle((iter(magenta_dirs),
+                                                                    iter(commas))))
+                parts.append(')')
 
             if not have_dirs:
                 parts = parts[0:-2]