Fix 500 error on progress page with rubric that has 0 points

openassessment/xblock/lms_mixin.py

@@ -73,5 +73,6 @@ class LmsCompatibilityMixin(object):
         """
         return sum(
             max(option["points"] for option in criterion["options"])
+            if len(criterion["options"]) > 0 else 0
             for criterion in self.rubric_criteria
         )

openassessment/xblock/test/data/zero_points.xml

+<openassessment>
+    <title>Feedback only criterion</title>
+    <prompt>Test prompt</prompt>
+    <rubric>
+        <prompt>Test rubric prompt</prompt>
+        <criterion feedback="required">
+            <name>𝖋𝖊𝖊𝖉𝖇𝖆𝖈𝖐 𝖔𝖓𝖑𝖞</name>
+            <prompt>This criterion accepts only written feedback, so it has no options</prompt>
+        </criterion>
+    </rubric>
+    <assessments>
+        <assessment name="self-assessment" />
+    </assessments>
+</openassessment>

openassessment/xblock/test/test_lms.py

@@ -18,3 +18,7 @@ class LmsMixinTest(XBlockHandlerTestCase):
     @scenario('data/basic_scenario.xml')
     def test_max_score(self, xblock):
         self.assertEqual(xblock.max_score(), 20)
+
+    @scenario('data/zero_points.xml')
+    def test_max_score_zero_option_criteria(self, xblock):
+        self.assertEqual(xblock.max_score(), 0)