When I was looking into this issue: https://github.com/nose-devs/nose2/issues/215 I discovered some naming/behavior inconsistency between the "classmethod setUp", "setUp", and "classmethod setUpClass"

test_nose2_unittest_layers.py

"""
run with:

nose2 test_nose2_unittest_layers  --plugin nose2.plugins.layers --layer-reporter --verbose
"""
import time
import unittest


class Layer1(object):
    @classmethod
    def setUp(cls):
        """
        This is run once per class like the unittest setUpClass
        (https://docs.python.org/2/library/unittest.html#unittest.TestCase.setUpClass)
        not once per test method like the unittest setUp
        (https://docs.python.org/2/library/unittest.html#unittest.TestCase.setUp)
        TODO: what's up with that?
        """
        time.sleep(1)
        print("1 second elapsed")
        time.sleep(1)
        print("2 seconds elapsed")


class Layer2(Layer1):
    @classmethod
    def setUp(cls):
        """
        This is run once per class like the unittest setUpClass
        (https://docs.python.org/2/library/unittest.html#unittest.TestCase.setUpClass)
        not once per test method like the unittest setUp
        (https://docs.python.org/2/library/unittest.html#unittest.TestCase.setUp)
        TODO: what's up with that?
        """
        time.sleep(1)
        print("3 second elapsed")
        time.sleep(1)
        print("4 seconds elapsed")


class TestCaseLayer1(unittest.TestCase):
    layer = Layer1

    def test_truth(self):
        assert True

    def test_truth2(self):
        assert True


class TestCaseLayer2(TestCaseLayer1):
    layer = Layer2