How and where does py.test find fixtures

Question

Where and how does py.test look for fixtures? I have the same code in 2 files in the same folder. When I delete conftest.py, cmdopt cannot be found running tes

Answer 1

I had the same issue and spent a lot of time to find out a simple solution, this example is for others that have a similar situation as I had.

• conftest.py:

import pytest

pytest_plugins = [
 "some_package.sonoftest"
]

def pytest_addoption(parser):
  parser.addoption("--cmdopt", action="store", default="type1",
      help="my option: type1 or type2")

@pytest.fixture
def cmdopt(request):
  return request.config.getoption("--cmdopt")

• some_package/sonoftest.py:

import pytest

@pytest.fixture
def sono_cmdopt(request):
  return request.config.getoption("--cmdopt")

• some_package/test_sample.py

def test_answer1(cmdopt):
  if cmdopt == "type1":
      print ("first")
  elif cmdopt == "type2":
      print ("second")
  assert 0 # to see what was printed

def test_answer2(sono_cmdopt):
  if sono_cmdopt == "type1":
      print ("first")
  elif sono_cmdopt == "type2":
      print ("second")
  assert 0 # to see what was printed

You can find a similar example here: https://github.com/pytest-dev/pytest/issues/3039#issuecomment-464489204 and other here https://stackoverflow.com/a/54736376/6655459

Description from official pytest documentation: https://docs.pytest.org/en/latest/reference.html?highlight=pytest_plugins#pytest-plugins

As a note that the respective directories referred to in some_package.test_sample" need to have __init__.py files for the plugins to be loaded by pytest