Using function scoped fixture to setup a class

Question

I have a fixture in conftest.py with a function scope.

@pytest.fixture()
def registration_setup(
    test_data, # fixture 1
    credentials, # fixture 2
    deployment # fixture 3
    deployment_object # fixture 4
):
    # pre-test cleanup
    do_cleanup()
    yield
    # post-test cleanup
    do_cleanup()

I use it in a test class like this:

class TestClass:

    @pytest.fixture(autouse=True)
    def _inventory_cleanup(self, registration_setup):
        log('Cleanup Done!')
    
    def test_1():
        ...

    def test_2():
        ...
    
    def test_3():
        ...

Now I want to create a new test class where I run the registartion_setup fixture once for the entire class. The desired behaviour here is, First the pre-test cleanup executes and then all the tests in the new test class execute, followed by the post-test cleanup. How can I achieve this, thanks for the help.

Answer 1

Huge thanks to @Marco.S for his answer. Just a small additional check to get it to work

def reg_setup(request):
    if 'TestClassWhereFixtureShouldRunOnlyOnce' in request.node.nodeid:
        if not request.config.first_test_executed:
            # pre-test cleanup
            do_cleanup()
            request.config.first_test_executed = True
        yield
        if 'test_last' in request.node.nodeid: # Check for the last test case.
            # post-test cleanup
            do_cleanup()
    else:
        # pre-test cleanup
        do_cleanup()
        yield
        # post-test cleanup
        do_cleanup()