Apply a default marker to all unmarked tests

[mrmundt]

Hi, all,

Hopefully this isn't a unique question and one of you has come across it already. I am trying to revamp/convert a large testing suite that was written with nosetest in mind. In the existing test suite, there is some logic that will check if a test has a attribute, and if there is no attribute, it assigns smoke and nightly by default - but of course, it's designed to work with nosetest attributes, not pytest.mark markers.

Is there an equivalent way to do so using pytest.mark? My initial thought was to do something like this in the conftest.py:

def pytest_collection_modifyitems(items, config):
    """
    Add `smoke` and `nightly` markers for any unmarked test.
    """
    for item in items:
        if not any(item.iter_markers()):
            item.add_marker("smoke")
            item.add_marker("nightly")

But it doesn't seem to be working.

[The-Compiler]

Your example works fine for me FWIW.

[mrmundt]

Really? It doesn't select anything for me when I run pytest -m smoke.

[The-Compiler]

Yes, really:

$ cat conftest.py 
def pytest_collection_modifyitems(items, config):
    """
    Add `smoke` and `nightly` markers for any unmarked test.
    """
    for item in items:
        if not any(item.iter_markers()):
            item.add_marker("smoke")
            item.add_marker("nightly")

$ cat test_x.py 
def test_no_marker():
    pass

$ cat conftest.py 
def pytest_collection_modifyitems(items, config):
    """
    Add `smoke` and `nightly` markers for any unmarked test.
    """
    for item in items:
        if not any(item.iter_markers()):
            item.add_marker("smoke")
            item.add_marker("nightly")

$ pytest -m smoke
============================= test session starts ==============================
platform linux -- Python 3.9.2, pytest-6.2.3, py-1.10.0, pluggy-0.13.1
rootdir: /home/florian/tmp/defaultmarker, configfile: pytest.ini
plugins: forked-1.3.0, xdist-2.2.0, hypothesis-6.8.9, anyio-2.2.0
collected 1 item                                                               

test_x.py .                                                              [100%]

============================== 1 passed in 0.02s ===============================