fix: handle deleted questions (#328)

Step builder was raising `ValueError` if a question was deleted by the course author.

problem_builder/mentoring.py

@@ -890,12 +890,15 @@ def answer_mapper(self, answer_status):
         for step in steps:
             for answer in step.student_results:
                 if answer[1]['status'] == answer_status:
-                    answer_map.append({
-                        'id': answer[0],
-                        'details': answer[1],
-                        'step': step.step_number,
-                        'number': self.get_question_number(answer[0]),
-                    })
+                    try:
+                        answer_map.append({
+                            'id': answer[0],
+                            'details': answer[1],
+                            'step': step.step_number,
+                            'number': self.get_question_number(answer[0]),
+                        })
+                    except ValueError:
+                        pass  # The question has been deleted since the student answered it.
         return answer_map
 
     @property

problem_builder/platform_dependencies.py

@@ -29,10 +29,24 @@
 
 # pylint: disable=unused-import
 
+# TODO: It might make sense to handle imports separately. This part just
+#  separates the `StudentModule` import from others to avoid conflicting
+#  with `studentmodule` models in Juniper. Without this, a `RuntimeError`
+#  is raised, as it causes other modules to be imported with a full import
+#  path, which is not supported in Juniper.
+try:
+    from courseware.models import StudentModule
+except Exception:
+    try:
+        from lms.djangoapps.courseware.models import StudentModule
+    except ImportError:
+        # If we are not running within edx-platform
+        # (e.g., we are running problem-builder unit tests).
+        StudentModule = None
+
 try:
     # Koa and earlier: use shortened import path.
     # This will raise a warning in Koa, but that's OK.
-    from courseware.models import StudentModule
     from static_replace import replace_static_urls
     from student.models import AnonymousUserId
     from xblock_django.models import XBlockConfiguration
@@ -42,14 +56,12 @@
     #  of the former, and only exists on edx-platform master between Koa and Lilac).
     try:
         # Post-Koa: we must use the full import path.
-        from lms.djangoapps.courseware.models import StudentModule
         from common.djangoapps.static_replace import replace_static_urls
         from common.djangoapps.student.models import AnonymousUserId
         from common.djangoapps.xblock_django.models import XBlockConfiguration
     except ImportError:
         # If we get here, we are not running within edx-platform
         # (e.g., we are running problem-builder unit tests).
-        StudentModule = None
         replace_static_urls = None
         AnonymousUserId = None
         XBlockConfiguration = None

setup.py

@@ -28,7 +28,7 @@
 
 # Constants #########################################################
 
-VERSION = '4.1.12'
+VERSION = '4.1.13'
 
 # Functions #########################################################