Made skipping of symlink-related makemessages test smarter.

os.symlink() is available starting with Windows Vista but can fail at
runtime.

tests/i18n/commands/extraction.py

@@ -4,6 +4,7 @@ from __future__ import unicode_literals
 import os
 import re
 import shutil
+from unittest import SkipTest
 import warnings
 
 from django.core import management
@@ -314,11 +315,20 @@ class SymlinkExtractorTests(ExtractorTests):
         os.chdir(self._cwd)
 
     def test_symlink(self):
+        # On Python < 3.2 os.symlink() exists only on Unix
         if hasattr(os, 'symlink'):
             if os.path.exists(self.symlinked_dir):
                 self.assertTrue(os.path.islink(self.symlinked_dir))
             else:
+                # On Python >= 3.2) os.symlink() exists always but then can
+                # fail at runtime when user hasn't the needed permissions on
+                # WIndows versions that support symbolink links (>= 6/Vista).
+                # See Python issue 9333 (http://bugs.python.org/issue9333).
+                # Skip the test in that case
+                try:
                     os.symlink(os.path.join(self.test_dir, 'templates'), self.symlinked_dir)
+                except (OSError, NotImplementedError):
+                    raise SkipTest("os.symlink() is available on this OS but can't be used by this user.")
             os.chdir(self.test_dir)
             management.call_command('makemessages', locale=LOCALE, verbosity=0, symlinks=True)
             self.assertTrue(os.path.exists(self.PO_FILE))