Fixed a bug which would mark all MCQ and MCC questions' answers as correct

1. Due to the new evaluator, an unchecked bug, which marked all mcq and mcc attempts as correct, despite actually marking the wrong answer, has been fixed.
2. Added Test case to check for incorrect mcq and mcc questions
3. question.html would also render error msg for mcq and mcc questions. This has also been fixed.

4 files changed, 56 insertions, 45 deletions

diff --git a/yaksh/models.py b/yaksh/models.py
index d65970b..271ed6d 100644
--- a/yaksh/models.py
+++ b/yaksh/models.py
@@ -1059,28 +1059,25 @@ class AnswerPaper(models.Model):
             For code questions success is True only if the answer is correct.
         """
 
-        result = {'success': True, 'error': ['Incorrect answer'], 'weight': 0.0}
-        correct = False
+        result = {'success': False, 'error': ['Incorrect answer'], 'weight': 0.0}
         if user_answer is not None:
             if question.type == 'mcq':
                 expected_answer = question.get_test_case(correct=True).options
                 if user_answer.strip() == expected_answer.strip():
-                    correct = True
+                    result['success'] = True
                     result['error'] = ['Correct answer']
             elif question.type == 'mcc':
                 expected_answers = []
                 for opt in question.get_test_cases(correct=True):
                     expected_answers.append(opt.options)
                 if set(user_answer) == set(expected_answers):
+                    result['success'] = True
                     result['error'] = ['Correct answer']
-                    correct = True
             elif question.type == 'code':
                 user_dir = self.user.profile.get_user_dir()
                 json_result = code_server.run_code(question.language, json_data, user_dir)
                 result = json.loads(json_result)
-                if result.get('success'):
-                    correct = True
-        return correct, result
+        return result
 
     def regrade(self, question_id):
         try:
@@ -1105,10 +1102,10 @@ class AnswerPaper(models.Model):
             answer = user_answer.answer
         json_data = question.consolidate_answer_data(answer) \
                             if question.type == 'code' else None
-        correct, result = self.validate_answer(answer, question, json_data)
-        user_answer.correct = correct
+        result = self.validate_answer(answer, question, json_data)
+        user_answer.correct = result.get('success')
         user_answer.error = result.get('error')
-        if correct:
+        if result.get('success'):
             user_answer.marks = (question.points * result['weight'] / 
                 question.get_maximum_test_case_weight()) \
                 if question.partial_grading and question.type == 'code' else question.points
diff --git a/yaksh/templates/yaksh/question.html b/yaksh/templates/yaksh/question.html
index 7cbca57..6473c2f 100644
--- a/yaksh/templates/yaksh/question.html
+++ b/yaksh/templates/yaksh/question.html
@@ -161,33 +161,11 @@ function call_skip(url)
                  </div>
                  <div class="panel-body">
                      {% if question.type == "mcq" %}
-                    {% if error_message %}
-                        <p>
-                        <div class="panel panel-danger">
-                        <div class="panel-heading">
-                        {% for err in error_message %}
-                            {{ err }}
-                        {% endfor %}
-                        </div>
-                        </div>
-                        </p>
-                     {% endif %}
                      {% for test_case in test_cases %}
                      <input name="answer" type="radio" value="{{ test_case.options }}" />{{ test_case.options|safe }} <br/>
                      {% endfor %}
                      {% endif %}
                      {% if question.type == "mcc" %}
-                    {% if error_message %}
-                        <p>
-                        <div class="panel panel-danger">
-                        <div class="panel-heading">
-                        {% for err in error_message %}
-                            {{ err }}
-                        {% endfor %}
-                        </div>
-                        </div>
-                        </p>
-                     {% endif %}
                      {% for test_case in test_cases %}
                      <input name="answer" type="checkbox" value="{{ test_case.options }}"> {{ test_case.options|safe }}
                      <br>
diff --git a/yaksh/test_models.py b/yaksh/test_models.py
index 48dfb8e..1a6bcba 100644
--- a/yaksh/test_models.py
+++ b/yaksh/test_models.py
@@ -533,22 +533,22 @@ class AnswerPaperTestCases(unittest.TestCase):
         )
         self.mcc_based_testcase.save()
 
-    def test_validate_and_regrade_mcc_question(self):
+    def test_validate_and_regrade_mcc_correct_answer(self):
         # Given
         mcc_answer = ['a']
         self.answer = Answer(question=self.question3,
-            answer=mcc_answer,
-        )
+                             answer=mcc_answer,
+                             )
         self.answer.save()
         self.answerpaper.answers.add(self.answer)
 
         # When
         json_data = None
-        correct, result = self.answerpaper.validate_answer(mcc_answer,
-                self.question3, json_data)
+        result = self.answerpaper.validate_answer(mcc_answer,
+                                                  self.question3, json_data
+                                                  )
 
         # Then
-        self.assertTrue(correct)
         self.assertTrue(result['success'])
         self.assertEqual(result['error'], ['Correct answer'])
         self.answer.correct = True
@@ -570,7 +570,7 @@ class AnswerPaperTestCases(unittest.TestCase):
         self.assertEqual(self.answer.marks, 0)
         self.assertFalse(self.answer.correct)
 
-    def test_validate_and_regrade_mcq_question(self):
+    def test_validate_and_regrade_mcq_correct_answer(self):
         # Given
         mcq_answer = 'a'
         self.answer = Answer(question=self.question2,
@@ -581,11 +581,11 @@ class AnswerPaperTestCases(unittest.TestCase):
 
         # When
         json_data = None
-        correct, result = self.answerpaper.validate_answer(mcq_answer,
-                self.question2, json_data)
+        result = self.answerpaper.validate_answer(mcq_answer,
+                                                  self.question2, json_data
+                                                  )
 
         # Then
-        self.assertTrue(correct)
         self.assertTrue(result['success'])
         self.answer.correct = True
         self.answer.marks = 1
@@ -607,6 +607,42 @@ class AnswerPaperTestCases(unittest.TestCase):
         self.assertFalse(self.answer.correct)
 
 
+    def test_mcq_incorrect_answer(self):
+        # Given
+        mcq_answer = 'a'
+        self.answer = Answer(question=self.question2,
+            answer=mcq_answer,
+        )
+        self.answer.save()
+        self.answerpaper.answers.add(self.answer)
+
+        # When
+        json_data = None
+        result = self.answerpaper.validate_answer(mcq_answer,
+                                                  self.question2, json_data
+                                                  )
+
+        # Then
+        self.assertTrue(result['success'])
+
+    def test_mcc_incorrect_answer(self):
+        # Given
+        mcc_answer = ['b']
+        self.answer = Answer(question=self.question3,
+                             answer=mcc_answer,
+                             )
+        self.answer.save()
+        self.answerpaper.answers.add(self.answer)
+
+        # When
+        json_data = None
+        result = self.answerpaper.validate_answer(mcc_answer,
+                                                  self.question3, json_data
+                                                  )
+
+        # Then
+        self.assertFalse(result['success'])
+
     def test_answerpaper(self):
         """ Test Answer Paper"""
         self.assertEqual(self.answerpaper.user.username, 'demo_user')
diff --git a/yaksh/views.py b/yaksh/views.py
index 7ecf6aa..0d54f8a 100644
--- a/yaksh/views.py
+++ b/yaksh/views.py
@@ -488,12 +488,12 @@ def check(request, q_id, attempt_num=None, questionpaper_id=None):
         # safely in a separate process (the code_server.py) running as nobody.
         json_data = current_question.consolidate_answer_data(user_answer) \
                         if current_question.type == 'code' else None
-        correct, result = paper.validate_answer(user_answer, current_question, json_data)
-        if correct or result.get('success'):
+        result = paper.validate_answer(user_answer, current_question, json_data)
+        if result.get('success'):
             new_answer.marks = (current_question.points * result['weight'] / 
                 current_question.get_maximum_test_case_weight()) \
                 if current_question.partial_grading and current_question.type == 'code' else current_question.points
-            new_answer.correct = correct
+            new_answer.correct = result.get('success')
             error_message = None
             new_answer.error = json.dumps(result.get('error'))
             next_question = paper.completed_question(current_question.id)