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

I use metaclasses and decorators for generate tests. You can check my implementation python_wrap_cases. This library doesn't require any test frameworks.

Your example:

import unittest
from python_wrap_cases import wrap_case


@wrap_case
class TestSequence(unittest.TestCase):

    @wrap_case("foo", "a", "a")
    @wrap_case("bar", "a", "b")
    @wrap_case("lee", "b", "b")
    def testsample(self, name, a, b):
        print "test", name
        self.assertEqual(a, b)

Console output:

testsample_u'bar'_u'a'_u'b' (tests.example.test_stackoverflow.TestSequence) ... test bar
FAIL
testsample_u'foo'_u'a'_u'a' (tests.example.test_stackoverflow.TestSequence) ... test foo
ok
testsample_u'lee'_u'b'_u'b' (tests.example.test_stackoverflow.TestSequence) ... test lee
ok

Also you may use generators. For example this code generate all possible combinations of tests with arguments a__list and b__list

import unittest
from python_wrap_cases import wrap_case


@wrap_case
class TestSequence(unittest.TestCase):

    @wrap_case(a__list=["a", "b"], b__list=["a", "b"])
    def testsample(self, a, b):
        self.assertEqual(a, b)

Console output:

testsample_a(u'a')_b(u'a') (tests.example.test_stackoverflow.TestSequence) ... ok
testsample_a(u'a')_b(u'b') (tests.example.test_stackoverflow.TestSequence) ... FAIL
testsample_a(u'b')_b(u'a') (tests.example.test_stackoverflow.TestSequence) ... FAIL
testsample_a(u'b')_b(u'b') (tests.example.test_stackoverflow.TestSequence) ... ok