参数化 pytest - 也将参数传递给设置和拆卸

Question

How can I pass same parameters to setup and teardown functions as which I pass to test function?

import pytest

test_data = [("3+5", 8), ("2+4", 6), ("6*9", 42)]


@pytest.mark.parametrize("test_input,expected", test_data)
def test_eval(test_input, expected):
    assert eval(test_input) == expected


def setup():
    print("setup")


def teardown():
    print("teardown")

In my real usecase I would initialize and clean database according to parameters passed to test function.

I have read examples, but none of those seem to cover case where all setup, test and teardown are parameterized.

Answer 1

Use fixture for the setup and teardown, you can send the paramters to it

test_data = [("3+5", 8), ("2+4", 6), ("6*9", 42)]


@pytest.fixture(scope='function', autouse=True)
def setup_and_teardown(test_input, expected):
    print("setup")
    print('Parameters:', test_input, expected)
    yield
    print("teardown")


@pytest.mark.parametrize("test_input,expected", test_data)
def test_eval(test_input, expected):
    assert eval(test_input) == expected
    print("*************************************")

Output:

setup
test_input: 3+5 expected: 8
PASSED                                 [ 33%]*************************************
teardown
setup
test_input: 2+4 expected: 6
PASSED                                 [ 66%]*************************************
teardown
setup
test_input: 6*9 expected: 42
FAILED                                [100%]
Tests\Example_test.py:34 (test_eval[6*9-42])
54 != 42

Expected :42
Actual   :54
<Click to see difference>

test_input = '6*9', expected = 42

    @pytest.mark.parametrize("test_input,expected", test_data)
    def test_eval(test_input, expected):
>       assert eval(test_input) == expected
E       assert 54 == 42