fix: move course_end_date property to InheritanceMixin

xmodule/capa_block.py

@@ -787,18 +787,6 @@ def generate_report_data(self, user_state_iterator, limit_responses=None):
                 }
                 yield (user_state.username, report)
 
-    @property
-    def course_end_date(self):
-        """
-        Return the end date of the problem's course
-        """
-
-        try:
-            course_block_key = self.runtime.course_entry.structure['root']
-            return self.runtime.course_entry.structure['blocks'][course_block_key].fields['end']
-        except (AttributeError, KeyError):
-            return None
-
     def get_seed(self):
         """
         Generate the seed if not set and return it.

xmodule/modulestore/inheritance.py

@@ -256,12 +256,24 @@ def close_date(self):
         can be submitted till due date and the graceperiod. If no
         graceperiod, then the close date is same as the due date.
         """
-        due_date = self.due
+        due_date = self.due or self.course_end_date
 
         if self.graceperiod is not None and due_date:
             return due_date + self.graceperiod
         return due_date
 
+    @property
+    def course_end_date(self):
+        """
+        Return the end date of the problem's course
+        """
+
+        try:
+            course_block_key = self.runtime.course_entry.structure['root']
+            return self.runtime.course_entry.structure['blocks'][course_block_key].fields['end']
+        except (AttributeError, KeyError):
+            return None
+
     def is_past_due(self):
         """
         Returns the boolean identifying if the submission due date has passed.

xmodule/tests/test_capa_block.py

@@ -656,7 +656,7 @@ def test_closed(self):
                                    due=self.yesterday_str)
         assert block.closed()
 
-    @patch.object(ProblemBlock, 'course_end_date', new_callable=PropertyMock)
+    @patch('xmodule.modulestore.inheritance.InheritanceMixin.course_end_date', new_callable=PropertyMock)
     def test_closed_for_archive(self, mock_course_end_date):
 
         # Utility to create a datetime object in the past