Fixed command testcases to work with Django 1.5

Since Django 1.5 CommandError is raised further instead of changing it
to SystemExist as was the case before.

trans/tests/commands.py

@@ -24,8 +24,15 @@ Tests for management commands.
 
 from trans.tests.models import RepoTestCase
 from django.core.management import call_command
+import django
 from trans.search import flush_index
 
+# Django 1.5 changes behavior here
+if django.VERSION >= (1, 5):
+    COMMAND_EXCEPTION = CommandError
+else:
+    COMMAND_EXCEPTION = SystemExit
+
 
 class ImportProjectTest(RepoTestCase):
     def test_import(self):
@@ -84,7 +91,7 @@ class ImportProjectTest(RepoTestCase):
         Test of correct handling of missing project.
         '''
         self.assertRaises(
-            SystemExit,
+            COMMAND_EXCEPTION,
             call_command,
             'import_project',
             'test',
@@ -99,7 +106,7 @@ class ImportProjectTest(RepoTestCase):
         '''
         self.create_project()
         self.assertRaises(
-            SystemExit,
+            COMMAND_EXCEPTION,
             call_command,
             'import_project',
             'test',
@@ -159,14 +166,14 @@ class CheckGitTest(RepoTestCase):
 
     def test_nonexisting_project(self):
         self.assertRaises(
-            SystemExit,
+            COMMAND_EXCEPTION,
             self.do_test,
             'notest',
         )
 
     def test_nonexisting_subproject(self):
         self.assertRaises(
-            SystemExit,
+            COMMAND_EXCEPTION,
             self.do_test,
             'test/notest',
         )