Python unittest - Ran 0 tests in 0.000s

python unit-testing python-unittest python-module
MattSom picture MattSom · May 13, 2017 · Viewed 20.3k times · Source

So I want to do this code Kata for practice. I want to implement the kata with tdd in separate files:

The algorithm:

# stringcalculator.py  
def Add(string):
   return 1

and the tests:

# stringcalculator.spec.py 
from stringcalculator import Add
import unittest

class TestStringCalculator(unittest.TestCase):
    def add_returns_zero_for_emptyString(self):
        self.assertEqual(Add(' '), 0)

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

When running the testfile, I get:

Ran 0 tests in 0.000s

OK

It should return one failed test however. What do I miss here?

Answer

abccd picture abccd · May 13, 2017

As stated in the python unittest doc:

The simplest TestCase subclass will simply implement a test method (i.e. a method whose name starts with test)

So you will need to change your method name to something like this:

def test_add_returns_zero_for_emptyString(self):
    self.assertEqual(Add(' '), 0)

Related questions

How do I run all Python unit tests in a directory?

I have a directory that contains my Python unit tests. Each unit test module is of the form test_*.py. I am attempting to make a file called all_test.py that will, you guessed it, run all files in …

Read More
Running single test from unittest.TestCase via command line

In our team, we define most test cases like this: One "framework" class ourtcfw.py: import unittest class OurTcFw(unittest.TestCase): def setUp: # something # other stuff that we want to use everywhere and a lot of test cases like testMyCase.…

Read More
Explain the "setUp" and "tearDown" Python methods used in test cases

Can anyone explain the use of Python's setUp and tearDown methods while writing test cases apart from that setUp is called immediately before calling the test method and tearDown is called immediately after it has been called?

Read More