Creating Tests

dscreate offers a couple options for adding tests to your curriculum materials.

NOTE: All tests are created and run using the Tests class within the compose.tests subdirectory.:

from dscreate.compose.tests import Tests
tests = Tests()

Below, is an example of a test for a simple problem. In this scenario a student is tasked with generating the list [1,2,3].

Writing Test Functions

#__SOLUTION__

def test_function(student_answer):
   if student_answer == [1,2,3]:
      return True


tests.save(test_function, 'first_test')

Running a test:

student_solution = [1,2,2]

tests.run('first_test', student_solution)
tests.run('first_test', [1,2,3])

>>>first_test: ❌
>>>first_test: ✅

Test function can use multiple arguments:

#__SOLUTION__
def multiple_arg_test(arg1, arg2, arg3, arg4):
   if arg1 != [1,2,3]:
      return False
   elif arg2 != [3,2,1]:
      return False
   elif arg3 != 'hello world':
      return False
   elif arg4 != 51:
      return False
   else:
      return True

tests.save(multiple_arg_test, 'multiple_arguments')

Running a multiple argument test:

student_answer = [1,2,3], [3,2,1], 'hello world', 51
tests.run('multiple_arguments', *student_answer)

student_answer = [1,2,3], [3,2,1], 'hello flatiron', 51
tests.run('multiple_arguments', *student_answer)

>>>multiple_arguments: ✅
>>>multiple_arguments: ❌

If you would like to output the result of the test instead of ✅ or ❌, you can set assertion=False:

#__SOLUTION__
def output_test(function):
   def solution(a,b):
      return a+b

   student = function(1,2)
   answer = solution(1,2)
   if student != answer:
      return f"Your function returned {student}, but should return {answer}!"
   else:
      return f'Your function returned the correct answer for 1 + 2!'


tests.save(output_test, 'output_test', assertion=False)

Running a test that returns the output of the test function:

def student_answer_wrong(a,b):
   return a-b

def student_answer_correct(a,b):
   return a+b

tests.run('output_test', student_answer_wrong)
tests.run('output_test', student_answer_correct)

>>>output_test: Your function returned -1, but should return 3!
>>>output_test: Your function returned the correct answer for 1 + 2!

Writing a Test Class

If you have multiple tests you’d like to run, the easiest solution would be create a class like below

• All test methods must begin with the word `test`

• If you would like to return the output of a test, set the argument output=True for the test method.

Below is an example of a test class for the following student task:

“In the cell below, create a class that has an attribute called “attribute” and a method called “method”. The method should return the number 5.”

#__SOLUTION__
class ExampleTest:

   def __init__(self, student_answer):
      self.student_answer = student_answer()

   def test_for_attribute(self):
      if hasattr(self.student_answer, 'attribute'):
            return True

   def test_method_output(self, output=True):
      try:
            result = self.student_answer.method()
            if result == 5:
               return 'Your method correctly returned 5!'
            else:
               return f'Your method returned {result} when it should have returned 5!'
      except:
            return 'Your method threw an error.'


tests.save(ExampleTest, 'Class_Example')

Running the test class:

class StudentSolutionCorrect:

   def __init__(self):
      self.attribute = True

   def method(self):
      return 5

tests.run('Class_Example', StudentSolutionCorrect)

>>>test_for_attribute: ✅
>>>test_method_output: Your method correctly returned 5!

class StudentSolutionWrong:

   def method(self):
      return 3

tests.run('Class_Example', StudentSolutionWrong)

>>>test_for_attribute: ❌
>>>test_method_output: Your method returned 3 when it should have returned 5!