added unit tests to add/remove course tab utility functions.

cms/djangoapps/contentstore/tests/test_utils.py

 """ Tests for utils. """
 from contentstore import utils
 import mock
+import collections
 from django.test import TestCase
 from xmodule.modulestore.tests.factories import CourseFactory
 from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase
@@ -70,3 +71,80 @@ class UrlReverseTestCase(ModuleStoreTestCase):
             'https://edge.edx.org/courses/edX/edX101/How_to_Create_an_edX_Course/about',
             utils.get_url_reverse('https://edge.edx.org/courses/edX/edX101/How_to_Create_an_edX_Course/about', course)
         )
+
+
+class ExtraPanelTabTestCase(TestCase):
+    """ Tests adding and removing extra course tabs. """
+
+    def get_tab_type_dicts(self, tab_types):
+        """ Returns an array of tab dictionaries. """
+        if tab_types:
+            return [{'tab_type': tab_type} for tab_type in tab_types.split(',')]
+        else:
+            return []
+
+    def get_course_with_tabs(self, tabs=[]):
+        """ Returns a mock course object with a tabs attribute. """
+        course = collections.namedtuple('MockCourse', ['tabs'])
+        if isinstance(tabs, basestring):
+            course.tabs = self.get_tab_type_dicts(tabs)
+        else:
+            course.tabs = tabs
+        return course
+
+    def add_extra_panel_tab(self):
+        """ Tests if a tab can be added to a course tab list. """
+        for tab_type in utils.EXTRA_TAB_PANELS.keys():
+            tab = utils.EXTRA_TAB_PANELS.get(tab_type)
+
+            # test adding with changed = True
+            for tab_setup in ['', 'x', 'x,y,z']:
+                course = self.get_course_with_tabs(tab_setup)
+                expected_tabs = course.tabs + tab
+                changed, actual_tabs = utils.add_extra_panel_tab(tab_type, course)
+                self.assertTrue(changed)
+                self.assertEqual(actual_tabs, expected_tabs)
+
+            # test adding with changed = False
+            tab_test_setup = [
+                [tab],
+                [tab, self.get_tab_type_dicts('x,y,z')],
+                [self.get_tab_type_dicts('x,y'), tab, self.get_tab_type_dicts('z')],
+                [self.get_tab_type_dicts('x,y,z'), tab]]
+
+            for tab_setup in tab_test_setup:
+                course = self.get_course_with_tabs(tab_setup)
+                expected_tabs = course.tabs
+                changed, actual_tabs = utils.add_extra_panel_tab(tab_type, course)
+                self.assertFalse(changed)
+                self.assertEqual(actual_tabs, expected_tabs)
+
+    def remove_tab_test(self):
+        """ Tests if a tab can be removed from a course tab list. """
+        for tab_type in utils.EXTRA_TAB_PANELS.keys():
+            tab = utils.EXTRA_TAB_PANELS.get(tab_type)
+
+            # test removing with changed = True
+            tab_test_setup = [
+                [tab],
+                [tab, self.get_tab_type_dicts('x,y,z')],
+                [self.get_tab_type_dicts('x,y'), tab, self.get_tab_type_dicts('z')],
+                [self.get_tab_type_dicts('x,y,z'), tab]]
+
+            for tab_setup in tab_test_setup:
+                course = self.get_course_with_tabs(tab_setup)
+                expected_tabs = [t for t in course.tabs if t != utils.EXTRA_TAB_PANELS.get(tab_type)]
+                changed, actual_tabs = utils.remove_extra_panel_tab(tab_type, course)
+                self.assertTrue(changed)
+                self.assertEqual(actual_tabs, expected_tabs)
+
+            # test removing with changed = False
+            for tab_setup in ['', 'x', 'x,y,z']:
+                course = self.get_course_with_tabs(tab_setup)
+                expected_tabs = course.tabs
+                print "expected_tabs = "
+                print expected_tabs
+                changed, actual_tabs = utils.remove_extra_panel_tab(tab_type, course)
+                self.assertFalse(changed)
+                self.assertEqual(actual_tabs, expected_tabs)
+