How do you generate dynamic (parameterized) unit tests in python?

Question

I have some kind of test data and want to create a unit test for each item. My first idea was to do it like this:

import unittest

l = [[\"foo\", \"a\", \"a\         


        

Answer 1

load_tests is a little known mechanism introduced in 2.7 to dynamically create a TestSuite. With it, you can easily create parametrized tests.

For example:

import unittest

class GeneralTestCase(unittest.TestCase):
    def __init__(self, methodName, param1=None, param2=None):
        super(GeneralTestCase, self).__init__(methodName)

        self.param1 = param1
        self.param2 = param2

    def runTest(self):
        pass  # Test that depends on param 1 and 2.


def load_tests(loader, tests, pattern):
    test_cases = unittest.TestSuite()
    for p1, p2 in [(1, 2), (3, 4)]:
        test_cases.addTest(GeneralTestCase('runTest', p1, p2))
    return test_cases

That code will run all the TestCases in the TestSuite returned by load_tests. No other tests are automatically run by the discovery mechanism.

Alternatively, you can also use inheritance as shown in this ticket: http://bugs.python.org/msg151444