Reveal student input at state of problem reset back to student

common/lib/xmodule/xmodule/capa_module.py

+import cgi
 import datetime
 import dateutil
 import dateutil.parser
@@ -236,16 +237,33 @@ class CapaModule(XModule):
                 #   to avoid bricking of problem as much as possible
 
                 # Presumably, student submission has corrupted LoncapaProblem HTML.
-                #   So, let's try generate a fresh LoncapaProblem
+                #   First, pull down all student answers
+                student_answers = self.lcp.student_answers
+                answer_ids = student_answers.keys()
+
+                # Some inputtypes, such as dynamath, have additional "hidden" state that
+                #   is not exposed to the student. Keep those hidden
+                hidden_state_keywords = ['dynamath']
+                for answer_id in answer_ids:
+                    for hidden_state_keyword in hidden_state_keywords:
+                        if answer_id.find(hidden_state_keyword) >= 0:
+                            student_answers.pop(answer_id)
+
+                #   Next, generate a fresh LoncapaProblem
                 self.lcp = LoncapaProblem(self.definition['data'], self.location.html_id(),
                                state=None, # Tabula rasa
                                seed=self.seed, system=self.system)
 
                 # Prepend a scary warning to the student
                 warning  = '<div class="capa_reset">'
-                warning += '<p>Problem state was corruped by invalid input. '
-                warning += 'Problem reset to initial state! '
-                warning += 'If problem persists, please contact the course staff.</p>'
+                warning += '<h2>Problem reset to initial state!</h2>'
+                warning += '<p>Problem state was corruped by invalid submission. The submission consisted of:</p>'
+                warning += '<ul>'
+                for student_answer in student_answers.values():
+                    if student_answer != '':
+                        warning += '<li>' + cgi.escape(student_answer) + '</li>'
+                warning += '</ul>'
+                warning += '<p>If problem persists, please contact the course staff.</p>'
                 warning += '</div>'
 
                 html = warning