How to test all elements from a list

Question

I have a list of integers. I want to supply each integer to the test method.

Here is how my test method looks like:

my_test.py:

import pytest

def test_mt(some_number):
    assert(some_number == 4)

conftest.py:

@pytest.fixture(scope="session", autouse=True)
def do_something(request):
    #Will be read from a file in real tests.
    #Path to the file is supplied via command line when running pytest
    list_int = [1, 2, 3, 4]
    #How to run test_mt test case for each element of the list_int

In case I prepared some arguments to be tested how can I supply them to a test case defined by the test_mt function in my case?

Do you want to apply the test_mt() function to each element of the list_int? — Chayan Bansal, Jan 30 '20 at 11:27
as @HarshaBiyani said, u can use for loop or even use map function — Chayan Bansal, Jan 30 '20 at 11:29
@HarshaBiyani I want to run `python -m pytest --test-cases /path/to/the/file` so there will be as many test case runs as integers in the file — Some Name, Jan 30 '20 at 11:30
@ChayanBansal You mean run it by hand in the for loop? So what is pytest for? — Some Name, Jan 30 '20 at 11:30
@HarshaBiyani In this simplified case I want to assert that each number equals to 4 — Some Name, Jan 30 '20 at 11:31
@SomeName: can't you modify `test_mt` by sending `some_number` as list? — Harsha Biyani, Jan 30 '20 at 11:34
@HarshaBiyani Would like to avoid it. And test each number in a separate test case. Sending the whole list is simple anyway. — Some Name, Jan 30 '20 at 11:35

score 4 · Accepted Answer · answered Jan 30 '20 at 12:35

One option is to use parametrize instead of fixture

def do_something():
    #Will be read from a file in real tests.
    #Path to the file is supplied via command line when running pytest
    list_int = [1, 2, 3, 4]
    for i in list_int:
        yield i


@pytest.mark.parametrize('some_number', do_something())
def test_mt(some_number):
    assert(some_number == 4)

This will run the test 4 times, each time with different number in some_number.

How to test all elements from a list

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