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A session-fixture which can look at all collected tests¶
A session-scoped fixture effectively has access to all collected test items. Here is an example of a fixture function which walks all collected tests and looks if their test class defines a callme method and calls it:
# content of conftest.py
import pytest
@pytest.fixture(scope="session", autouse=True)
def callattr_ahead_of_alltests(request):
print("callattr_ahead_of_alltests called")
seen = {None}
session = request.node
for item in session.items:
cls = item.getparent(pytest.Class)
if cls not in seen:
if hasattr(cls.obj, "callme"):
cls.obj.callme()
seen.add(cls)
test classes may now define a callme method which will be called ahead of running any tests:
# content of test_module.py
class TestHello:
@classmethod
def callme(cls):
print("callme called!")
def test_method1(self):
print("test_method1 called")
def test_method2(self):
print("test_method2 called")
class TestOther:
@classmethod
def callme(cls):
print("callme other called")
def test_other(self):
print("test other")
# works with unittest as well ...
import unittest
class SomeTest(unittest.TestCase):
@classmethod
def callme(self):
print("SomeTest callme called")
def test_unit1(self):
print("test_unit1 method called")
If you run this without output capturing:
$ pytest -q -s test_module.py
callattr_ahead_of_alltests called
callme called!
callme other called
SomeTest callme called
test_method1 called
.test_method2 called
.test other
.test_unit1 method called
.
4 passed in 0.12s