Allow negative marks for a question

yaksh/models.py

@@ -1367,6 +1367,14 @@ class Question(models.Model):
  # The type of question.
  type = models.CharField(max_length=24, choices=question_types)
 
+ # Negative marks for the question
+ negative_marks = models.FloatField(
+ default=0.0,
+ help_text='In Percentage eg: 25, '
+ 'means 0.25 will be negative marks if question is for 1 mark'
+ )
+
+
  # Is this question active or not. If it is inactive it will not be used
  # when creating a QuestionPaper.
  active = models.BooleanField(default=True)
@@ -1732,10 +1740,16 @@ class Answer(models.Model):
  comment = models.TextField(null=True, blank=True)
 
  def set_marks(self, marks):
- if marks > self.question.points:
- self.marks = self.question.points
- else:
- self.marks = marks
+ points = self.question.points
+ qtype = self.question.type
+ if marks > points:
+ marks = points
+ if qtype == 'mcq' or qtype == 'mcc':
+ wrong_fraction = points - marks
+ negative_marks = wrong_fraction * (self.question.negative_marks/100)
+ marks = marks - negative_marks
+ self.marks = marks
+ self.save()
 
  def set_comment(self, comments):
  self.comment = comments
@@ -2629,16 +2643,16 @@ def regrade(self, question_id, server_port=SERVER_POOL_PORT):
  if question.partial_grading and question.type == 'code':
  max_weight = question.get_maximum_test_case_weight()
  factor = result['weight']/max_weight
- user_answer.marks = question.points * factor
+ user_answer.set_marks(question.points * factor)
  else:
- user_answer.marks = question.points
+ user_answer.set_marks(question.points)
  else:
  if question.partial_grading and question.type == 'code':
  max_weight = question.get_maximum_test_case_weight()
  factor = result['weight']/max_weight
- user_answer.marks = question.points * factor
+ user_answer.set_marks(question.points * factor)
  else:
- user_answer.marks = 0
+ user_answer.set_marks(0)
  user_answer.save()
  self.update_marks('completed')
  return True, msg

yaksh/static/yaksh/js/add_question.js

@@ -183,6 +183,11 @@ function autosubmit()
 }
 
 $(document).ready(() => {
+ $("#id_negative_marks").closest("tr").hide()
+ let qtype = $("#id_type").val();
+ if (qtype === "mcq" || qtype === "mcc") {
+ $("#id_negative_marks").closest("tr").show()
+ }
  let option = $('#id_language').val();
  if(option === 'other') {
  $('#id_topic').closest('tr').show();
@@ -210,5 +215,10 @@ $(document).ready(() => {
  } else {
  $('#id_language').children("option[value='other']").show();
  }
- })
-});
+ if (value === "mcq" || value === "mcc") {
+ $("#id_negative_marks").closest("tr").show()
+ } else {
+ $("#id_negative_marks").closest("tr").hide()
+ }
+ });
+});

yaksh/test_models.py

@@ -1790,6 +1790,62 @@ def test_update_marks(self):
  self.assertTrue(self.answerpaper.passed)
  self.assertFalse(self.answerpaper.is_attempt_inprogress())
 
+ def test_update_marks_with_negative_marks(self):
+ # Given
+ question = self.answer_wrong.question
+ question.negative_marks = 25
+ question.save()
+
+ # When
+ self.answer_wrong.set_marks(1)
+ self.answerpaper.update_marks()
+
+ # Then
+ self.assertEqual(self.answerpaper.marks_obtained, 2)
+ self.assertEqual(self.answerpaper.percent, 66.67)
+
+ # When
+ answers = self.answerpaper.answers.filter(question=question)
+ for answer in answers:
+ answer.set_marks(0)
+ self.answerpaper.update_marks()
+
+ # Then
+ self.assertEqual(self.answerpaper.marks_obtained, 0.75)
+ self.assertEqual(self.answerpaper.percent, 25)
+
+ # When
+ for answer in answers:
+ self.answer_wrong.set_marks(-1)
+ self.answer_wrong.set_marks(0)
+ self.answerpaper.update_marks()
+
+ # Then
+ self.assertEqual(self.answerpaper.marks_obtained, 0.75)
+ self.assertEqual(self.answerpaper.percent, 25)
+
+ # When
+ for answer in answers:
+ self.answer_wrong.set_marks(0.5)
+ self.answerpaper.update_marks()
+
+ # Then
+ self.assertEqual(self.answerpaper.marks_obtained, 1.375)
+ self.assertEqual(self.answerpaper.percent, 45.83)
+
+ # Given
+ question.negative_marks = 0
+ question.save()
+
+ # When
+ for answer in answers:
+ self.answer_wrong.set_marks(0)
+ self.answerpaper.update_marks()
+
+ # Then
+ self.assertEqual(self.answerpaper.marks_obtained, 1)
+ self.assertEqual(self.answerpaper.percent, 33.33)
+
  def test_set_end_time(self):
  current_time = timezone.now()
  self.answerpaper.set_end_time(current_time)
@@ -1818,6 +1874,61 @@ def test_set_marks(self):
  self.assertEqual(self.answer_wrong.marks, 0.5)
  self.answer_wrong.set_marks(10.0)
  self.assertEqual(self.answer_wrong.marks, 1.0)
+ self.answer_wrong.set_marks(0)
+ self.assertEqual(self.answer_wrong.marks, 0)
+
+ def test_set_marks_with_negative_marks(self):
+ # Given
+ question = self.answer_wrong.question
+ question.negative_marks = 25
+ question.save()
+
+ # When
+ self.answer_wrong.set_marks(1)
+ # Then
+ self.assertEqual(self.answer_wrong.marks, 1)
+
+ # When
+ self.answer_wrong.set_marks(0)
+ # Then
+ self.assertEqual(self.answer_wrong.marks, -0.25)
+
+ # When
+ self.answer_wrong.set_marks(0.5)
+ # Then
+ self.assertEqual(self.answer_wrong.marks, 0.375)
+
+ # Given
+ question.negative_marks = 0
+ # When
+ self.answer_wrong.set_marks(1)
+ # Then
+ self.assertEqual(self.answer_wrong.marks, 1.0)
+
+ # When
+ self.answer_wrong.set_marks(0)
+ # Then
+ self.assertEqual(self.answer_wrong.marks, 0)
+
+ def test_no_negative_marks_except_mcq_mcc(self):
+ # Given
+ code_question = self.answer1.question
+ marks = self.answer1.marks
+ code_question.negative_marks = 25
+ code_question.save()
+
+ # When
+ self.answer1.set_marks(1)
+ # Then
+ self.assertEqual(self.answer1.marks, 1)
+
+ # When
+ self.answer1.set_marks(0)
+ # Then
+ self.assertEqual(self.answer1.marks, 0)
+
+ self.answer1.marks = marks
+ self.answer1.save()
 
  def test_get_latest_answer(self):
  latest_answer = self.answerpaper.get_latest_answer(self.question1.id)

yaksh/views.py

@@ -987,22 +987,24 @@ def _update_paper(request, uid, result):
  paper = new_answer.answerpaper_set.first()
 
  if result.get('success'):
- new_answer.marks = (current_question.points * result['weight'] /
-  current_question.get_maximum_test_case_weight()) \
+ marks = (current_question.points * result['weight'] /
+ current_question.get_maximum_test_case_weight()) \
  if current_question.partial_grading and \
  current_question.type == 'code' or \
  current_question.type == 'upload' else current_question.points
+ new_answer.set_marks(marks)
  new_answer.correct = result.get('success')
  error_message = None
  new_answer.error = json.dumps(result.get('error'))
  next_question = paper.add_completed_question(current_question.id)
  else:
- new_answer.marks = (current_question.points * result['weight'] /
-  current_question.get_maximum_test_case_weight()) \
+ marks = (current_question.points * result['weight'] /
+ current_question.get_maximum_test_case_weight()) \
  if current_question.partial_grading and \
  current_question.type == 'code' or \
  current_question.type == 'upload' \
  else 0
+ new_answer.set_marks(marks)
  error_message = result.get('error') \
  if current_question.type == 'code' or \
  current_question.type == 'upload' \