Fixture fails with "module" scope and numpy array as value #6497
Description
Minimal failing example:
import numpy as np import pytest @pytest.fixture(scope="module", params=[0, np.ones(2)]) def my_fixture(request): return request.param def test_stuff(my_fixture): passpytest output:
=============================================== test session starts ================================================ platform linux -- Python 3.8.1, pytest-5.3.3, py-1.8.1, pluggy-0.13.1 rootdir: /home/hkohr/git collected 2 items tmp.py .E [100%] ====================================================== ERRORS ====================================================== ____________________________________ ERROR at setup of test_stuff[my_fixture1] _____________________________________ cls = <class '_pytest.runner.CallInfo'>, func = <function call_runtest_hook.<locals>.<lambda> at 0x7f8b16fb03a0> when = 'setup', reraise = (<class '_pytest.outcomes.Exit'>, <class 'KeyboardInterrupt'>) @classmethod def from_call(cls, func, when, reraise=None) -> "CallInfo": #: context of invocation: one of "setup", "call", #: "teardown", "memocollect" start = time() excinfo = None try: > result = func() ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/runner.py:235: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/runner.py:208: in <lambda> lambda: ihook(item=item, **kwds), when=when, reraise=reraise ../miniconda/envs/tmp/lib/python3.8/site-packages/pluggy/hooks.py:286: in __call__ return self._hookexec(self, self.get_hookimpls(), kwargs) ../miniconda/envs/tmp/lib/python3.8/site-packages/pluggy/manager.py:93: in _hookexec return self._inner_hookexec(hook, methods, kwargs) ../miniconda/envs/tmp/lib/python3.8/site-packages/pluggy/manager.py:84: in <lambda> self._inner_hookexec = lambda hook, methods, kwargs: hook.multicall( ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/runner.py:120: in pytest_runtest_setup item.session._setupstate.prepare(item) ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/runner.py:365: in prepare col.setup() ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/python.py:1449: in setup fixtures.fillfixtures(self) ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/fixtures.py:294: in fillfixtures request._fillfixtures() ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/fixtures.py:473: in _fillfixtures item.funcargs[argname] = self.getfixturevalue(argname) ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/fixtures.py:483: in getfixturevalue return self._get_active_fixturedef(argname).cached_result[0] ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/fixtures.py:499: in _get_active_fixturedef self._compute_fixture_value(fixturedef) ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/fixtures.py:580: in _compute_fixture_value fixturedef.execute(request=subrequest) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ self = <FixtureDef argname='my_fixture' scope='module' baseid='tmp.py'> request = <SubRequest 'my_fixture' for <Function test_stuff[my_fixture1]>> def execute(self, request): for argname in self._dependee_fixture_argnames(request): fixturedef = request._get_active_fixturedef(argname) if argname != "request": fixturedef.addfinalizer(functools.partial(self.finish, request=request)) my_cache_key = self.cache_key(request) cached_result = getattr(self, "cached_result", None) if cached_result is not None: result, cache_key, err = cached_result > if my_cache_key == cache_key: E ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all() ../miniconda/envs/tmp/lib/python3.8/site-packages/_pytest/fixtures.py:895: ValueError ============================================ 1 passed, 1 error in 0.35s ============================================ I'm not sure if there's a good way to fix this. If not, perhaps the docs should mention that arrays should not be used as parameter values, or only with function scope.