background

python includes unittest in the standard module, but I didn't know how to use it right away, so I'll keep the template as a memo so that I can copy and paste it in other projects.

*Notes

From python2.7 and above, unittest can use setUpClass and tearDownClass, which are executed when the test class is initialized. For python2.6 and below, you can use these methods by importing a module called unittest2.

Code template

point

In unittest.main (), setUpClass → (setUp → tearDown) * Loop → tearDownClass is executed.
Methods for test must start with test in their name. e.g. test_hoge ()
Various types of assert methods are available, so please refer to python documentation.

# -*- coding: utf-8 -*-
import os, sys, unittest

class Sample():
	"""Class to be tested"""
	#Method to be tested
	def return_hoge(self):
		return 'hoge'

	#Method to be tested
	def return_poyo(self):
		return 'poyo'

class SampleTest(unittest.TestCase):
	"""A test class that tests a class"""
	CLS_VAL = 'none'

	#Called only once when the test class is initialized(python2.7 or more)
	@classmethod
	def setUpClass(cls):
		if sys.flags.debug: print('> setUpClass method is called.')
		#Execute heavy processing methods to prepare for testing
		cls.CLS_VAL = '> setUpClass : initialized!'
		if sys.flags.debug: print(cls.CLS_VAL)

	#Called only once when the test class is released(python2.7 or more)
	@classmethod
	def tearDownClass(cls):
		if sys.flags.debug: print('> tearDownClass method is called.')
		#Release the object prepared by setUpClass
		cls.CLS_VAL = '> tearDownClass : released!'
		if sys.flags.debug: print(cls.CLS_VAL)

	#Called every time the test method is executed
	def setUp(self):
		if sys.flags.debug: print(os.linesep + '> setUp method is called.')
		#Perform a light process to prepare for the test
		self.smpl = Sample()

	#Called after each test method execution
	def tearDown(self):
		if sys.flags.debug: print(os.linesep + '> tearDown method is called.')
		#Release the object prepared by setUp

	def test_hoge(self):
		expected = 'hoge'
		actual = self.smpl.return_hoge()
		self.assertEqual(expected, actual)

	def test_poyo(self):
		expected = 'poyo'
		actual = self.smpl.return_hoge() #Common mistake
		self.assertEqual(expected, actual)

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

From gitHub

Execution result

Put the -d flag on when running a python script to enter debug mode. (sys.flags.debug will be True.)

python -d /Users/you/Desktop/sample.py

> setUpClass method is called.
> setUpClass : heavy method

> setUp method is called.

> tearDown method is called.
.
> setUp method is called.
F
> tearDown method is called.
> tearDownClass method is called.
> tearDownClass : released

======================================================================
FAIL: test_poyo (__main__.SampleTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/you/Desktop/sample.py", line 54, in test_poyo
    self.assertEqual(expected, actual)
AssertionError: 'poyo' != 'hoge'

----------------------------------------------------------------------
Ran 2 tests in 0.001s

FAILED (failures=1)

Output when not in debug mode

 python /Users/you/Desktop/sample.py
.F
======================================================================
FAIL: test_poyo (__main__.SampleTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/you/Desktop/sample.py", line 54, in test_poyo
    self.assertEqual(expected, actual)
AssertionError: 'poyo' != 'hoge'

----------------------------------------------------------------------
Ran 2 tests in 0.000s

FAILED (failures=1)

Appendix

I don't think it's used much in small scripts, but if you need it, there is also an initialization method for each Module such as setUpModule.

python unit test template

background

Code template

Execution result