Add regression test and fix to allow free response questions to be marked as complete.

Author: rtibbles

contentcuration/contentcuration/models.py

@@ -2250,11 +2250,13 @@ def mark_complete(self):  # noqa C901
                     | (
                         # A non-blank question
                         ~Q(question="")
-                        # Non-blank answers
-                        & ~Q(answers="[]")
-                        # With either an input question or one answer marked as correct
+                        # Non-blank answers, unless it is a free response question
+                        # (which is allowed to have no answers)
+                        & (~Q(answers="[]") | Q(type=exercises.FREE_RESPONSE))
+                        # With either an input or free response question or one answer marked as correct
                         & (
                             Q(type=exercises.INPUT_QUESTION)
+                            | Q(type=exercises.FREE_RESPONSE)
                             | Q(answers__iregex=r'"correct":\s*true')
                         )
                     )

contentcuration/contentcuration/tests/test_contentnodes.py

@@ -1223,6 +1223,29 @@ def test_create_exercise_invalid_assessment_item_no_answers(self):
         new_obj.mark_complete()
         self.assertFalse(new_obj.complete)
 
+    def test_create_exercise_valid_assessment_item_free_response_no_answers(self):
+        licenses = list(
+            License.objects.filter(
+                copyright_holder_required=False, is_custom=False
+            ).values_list("pk", flat=True)
+        )
+        channel = testdata.channel()
+        new_obj = ContentNode(
+            title="yes",
+            kind_id=content_kinds.EXERCISE,
+            parent=channel.main_tree,
+            license_id=licenses[0],
+            extra_fields=self.new_extra_fields,
+        )
+        new_obj.save()
+        AssessmentItem.objects.create(
+            contentnode=new_obj,
+            question="This is a question",
+            type=exercises.FREE_RESPONSE,
+        )
+        new_obj.mark_complete()
+        self.assertTrue(new_obj.complete)
+
     def test_create_exercise_invalid_assessment_item_no_correct_answers(self):
         licenses = list(
             License.objects.filter(