Remove usage of unittest2

from comments when it was last touched it looks like workarounds for
unittest2 might be able to be dropped.

related: https://github.com/mtreinish/stestr/pull/265

simplify the workaround logic around unittest2 TestCase logic

Change-Id: Ibac9d0c2fa2f30605dd44ee58b84946464ea6449

requirements.txt

@@ -21,4 +21,3 @@ stevedore>=1.20.0 # Apache-2.0
 PrettyTable>=0.7.1 # BSD
 urllib3>=1.21.1 # MIT
 debtcollector>=1.2.0 # Apache-2.0
-unittest2>=1.1.0 # BSD

tempest/lib/base.py

@@ -14,29 +14,11 @@
 #    under the License.
 
 import os
-import sys
 
 import fixtures
-import pkg_resources
 import testtools
 
 
-def _handle_skip_exception():
-    try:
-        stestr_version = pkg_resources.parse_version(
-            pkg_resources.get_distribution("stestr").version)
-        stestr_min = pkg_resources.parse_version('2.5.0')
-        new_stestr = (stestr_version >= stestr_min)
-        import unittest
-        import unittest2
-        if sys.version_info >= (3, 5) and new_stestr:
-            testtools.TestCase.skipException = unittest.case.SkipTest
-        else:
-            testtools.TestCase.skipException = unittest2.case.SkipTest
-    except Exception:
-        pass
-
-
 class BaseTestCase(testtools.testcase.WithAttributes, testtools.TestCase):
     setUpClassCalled = False
 
@@ -51,18 +33,6 @@ class BaseTestCase(testtools.testcase.WithAttributes, testtools.TestCase):
         if hasattr(super(BaseTestCase, cls), 'setUpClass'):
             super(BaseTestCase, cls).setUpClass()
         cls.setUpClassCalled = True
-        # TODO(gmann): cls.handle_skip_exception is really workaround for
-        # testtools bug- https://github.com/testing-cabal/testtools/issues/272
-        # stestr which is used by Tempest internally to run the test switch
-        # the customize test runner(which use stdlib unittest) for >=py3.5
-        # else testtools.run.- https://github.com/mtreinish/stestr/pull/265
-        # These two test runner are not compatible due to skip exception
-        # handling(due to unittest2). testtools.run treat unittestt.SkipTest
-        # as error and stdlib unittest treat unittest2.case.SkipTest raised
-        # by testtools.TestCase.skipException.
-        # The below workaround can be removed once testtools fix issue# 272.
-        cls.orig_skip_exception = testtools.TestCase.skipException
-        _handle_skip_exception()
 
     @classmethod
     def tearDownClass(cls):
@@ -70,7 +40,6 @@ class BaseTestCase(testtools.testcase.WithAttributes, testtools.TestCase):
             super(BaseTestCase, cls).tearDownClass()
 
     def setUp(self):
-        testtools.TestCase.skipException = self.orig_skip_exception
         super(BaseTestCase, self).setUp()
         if not self.setUpClassCalled:
             raise RuntimeError("setUpClass does not calls the super's "

tempest/test.py

@@ -26,7 +26,6 @@ from tempest import clients
 from tempest.common import credentials_factory as credentials
 from tempest.common import utils
 from tempest import config
-from tempest.lib import base as lib_base
 from tempest.lib.common import api_microversion_fixture
 from tempest.lib.common import fixed_network
 from tempest.lib.common import profiler
@@ -142,19 +141,6 @@ class BaseTestCase(testtools.testcase.WithAttributes,
         # It should never be overridden by descendants
         if hasattr(super(BaseTestCase, cls), 'setUpClass'):
             super(BaseTestCase, cls).setUpClass()
-        # All the configuration checks that may generate a skip
-        # TODO(gmann): cls.handle_skip_exception is really workaround for
-        # testtools bug- https://github.com/testing-cabal/testtools/issues/272
-        # stestr which is used by Tempest internally to run the test switch
-        # the customize test runner(which use stdlib unittest) for >=py3.5
-        # else testtools.run.- https://github.com/mtreinish/stestr/pull/265
-        # These two test runner are not compatible due to skip exception
-        # handling(due to unittest2). testtools.run treat unittestt.SkipTest
-        # as error and stdlib unittest treat unittest2.case.SkipTest raised
-        # by testtools.TestCase.skipException.
-        # The below workaround can be removed once testtools fix issue# 272.
-        orig_skip_exception = testtools.TestCase.skipException
-        lib_base._handle_skip_exception()
         try:
             cls.skip_checks()
 
@@ -182,8 +168,6 @@ class BaseTestCase(testtools.testcase.WithAttributes,
                 raise value.with_traceback(trace)
             finally:
                 del trace  # to avoid circular refs
-        finally:
-            testtools.TestCase.skipException = orig_skip_exception
 
     @classmethod
     def tearDownClass(cls):

tempest/test_discover/test_discover.py

@@ -13,15 +13,10 @@
 #    under the License.
 
 import os
-import sys
+import unittest
 
 from tempest.test_discover import plugins
 
-if sys.version_info >= (2, 7):
-    import unittest
-else:
-    import unittest2 as unittest
-
 
 def load_tests(loader, tests, pattern):
     ext_plugins = plugins.TempestTestPluginManager()

tempest/tests/lib/test_base.py

@@ -48,7 +48,7 @@ class TestSetUpClass(base.BaseTestCase):
     @classmethod
     def setUpClass(cls):  # noqa
         """Simulate absence of super() call."""
-        cls.orig_skip_exception = cls.skipException
+        pass
 
     def setUp(self):
         try:

tempest/tests/test_test.py

@@ -14,7 +14,7 @@
 #    under the License.
 
 import os
-import sys
+import unittest
 from unittest import mock
 
 from oslo_config import cfg
@@ -34,12 +34,6 @@ from tempest.tests.lib import fake_credentials
 from tempest.tests.lib.services import registry_fixture
 
 
-if sys.version_info >= (2, 7):
-    import unittest
-else:
-    import unittest2 as unittest
-
-
 class LoggingTestResult(testtools.TestResult):
 
     def __init__(self, log, *args, **kwargs):