MESSAGE_TYPE: LINE_NUM:[OBJECT:] MESSAGE

import numpy
import doctest

def factorial(n):
   """
   Test for the factorial of 3 that should pass.
   >>> factorial(3)
   6

   Test for the factorial of 0 that should fail.
   >>> factorial(0)
   1
   """
   return numpy.arange(1, n+1).cumprod()[-1]

doctest.testmod()

python docstringtest.py -v
Trying:
    factorial(3)
Expecting:
    6
ok
Trying:
    factorial(0)
Expecting:
    1
**********************************************************************
File "docstringtest.py", line 11, in __main__.factorial
Failed example:
    factorial(0)
Exception raised:
    Traceback (most recent call last):
      File ".../doctest.py", line 1253, in __run
        compileflags, 1) in test.globs
      File "<doctest __main__.factorial[1]>", line 1, in <module>
        factorial(0)
      File "docstringtest.py", line 14, in factorial
        return numpy.arange(1, n+1).cumprod()[-1]
    IndexError: index out of bounds
1 items had no tests:
    __main__
**********************************************************************
1 items had failures:
   1 of   2 in __main__.factorial
2 tests in 2 items.
1 passed and 1 failed.
***Test Failed*** 1 failures.

import numpy
import unittest

def factorial(n):
    if n == 0:
      return 1

    if n < 0:
      raise ValueError, "Don't be so negative"

    return numpy.arange(1, n+1).cumprod()

class FactorialTest(unittest.TestCase):
    def test_factorial(self):
      #Test for the factorial of 3 that should pass.
      self.assertEqual(6, factorial(3)[-1])
      numpy.testing.assert_equal(numpy.array([1, 2, 6]), factorial(3))

    def test_zero(self):
      #Test for the factorial of 0 that should pass.
      self.assertEqual(1, factorial(0))

    def test_negative(self):
      #Test for the factorial of negative numbers that should fail.
      # It should throw a ValueError, but we expect IndexError
      self.assertRaises(IndexError, factorial(-10))

if __name__ == '__main__':
    unittest.main()

.E.
======================================================================
ERROR: test_negative (__main__.FactorialTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "unit_test.py", line 26, in test_negative
    self.assertRaises(IndexError, factorial(-10))
  File "unit_test.py", line 9, in factorial
    raise ValueError, "Don't be so negative"
ValueError: Don't be so negative

----------------------------------------------------------------------
Ran 3 tests in 0.001s

FAILED (errors=1)

from mock import MagicMock
import numpy
import unittest

class NuclearReactor():
    def __init__(self, n):
      self.n = n

    def do_work(self, msg):
      print "Working"

      return self.factorial(self.n, msg)

    def factorial(self, n, msg):
      print msg 

      if n == 0:
        return 1

      if n < 0:
        raise ValueError, "Core meltdown"

      return numpy.arange(1, n+1).cumprod()

class NuclearReactorTest(unittest.TestCase):
    def test_called(self):
      reactor = NuclearReactor(3)
      reactor.factorial = MagicMock(return_value=6)
      result = reactor.do_work("mocked")
      self.assertEqual(6, result)
      reactor.factorial.assert_called_with(3, "mocked")

    def test_unmocked(self):
      reactor = NuclearReactor(3)
      reactor.factorial(3, "unmocked")
      numpy.testing.assert_raises(ValueError)

if __name__ == '__main__':
     unittest.main()

Working
.unmocked
.
----------------------------------------------------------------------
Ran 2 tests in 0.000s

OK