Remove unnecessary unittest (#9596)

Now that we're using pytest more aggressively, I think we should start transitioning our tests to that style rather than continuing to use unittest. This PR removes some unnecessary uses of unittest I found.

I kept the test classes (while removing the inheritance from unittest.TestCase) where I felt like it added structure or logical grouping of tests.

I verified that pytest still finds all the tests in both this branch and master by running commands like:
```
pytest $(git diff --name-only master | grep -v windows_installer_integration_tests)
```

acme/tests/jose_test.py

@@ -6,51 +6,48 @@
 import pytest
 
 
-class JoseTest(unittest.TestCase):
-    """Tests for acme.jose shim."""
-
-    def _test_it(self, submodule, attribute):
-        if submodule:
-            acme_jose_path = 'acme.jose.' + submodule
-            josepy_path = 'josepy.' + submodule
-        else:
-            acme_jose_path = 'acme.jose'
-            josepy_path = 'josepy'
-        acme_jose_mod = importlib.import_module(acme_jose_path)
-        josepy_mod = importlib.import_module(josepy_path)
-
-        assert acme_jose_mod is josepy_mod
-        assert getattr(acme_jose_mod, attribute) is getattr(josepy_mod, attribute)
-
-        # We use the imports below with eval, but pylint doesn't
-        # understand that.
-        import josepy  # pylint: disable=unused-import
-
-        import acme  # pylint: disable=unused-import
-        acme_jose_mod = eval(acme_jose_path)  # pylint: disable=eval-used
-        josepy_mod = eval(josepy_path)  # pylint: disable=eval-used
-        assert acme_jose_mod is josepy_mod
-        assert getattr(acme_jose_mod, attribute) is getattr(josepy_mod, attribute)
-
-    def test_top_level(self):
-        self._test_it('', 'RS512')
-
-    def test_submodules(self):
-        # This test ensures that the modules in josepy that were
-        # available at the time it was moved into its own package are
-        # available under acme.jose. Backwards compatibility with new
-        # modules or testing code is not maintained.
-        mods_and_attrs = [('b64', 'b64decode',),
-                          ('errors', 'Error',),
-                          ('interfaces', 'JSONDeSerializable',),
-                          ('json_util', 'Field',),
-                          ('jwa', 'HS256',),
-                          ('jwk', 'JWK',),
-                          ('jws', 'JWS',),
-                          ('util', 'ImmutableMap',),]
-
-        for mod, attr in mods_and_attrs:
-            self._test_it(mod, attr)
+def _test_it(submodule, attribute):
+    if submodule:
+        acme_jose_path = 'acme.jose.' + submodule
+        josepy_path = 'josepy.' + submodule
+    else:
+        acme_jose_path = 'acme.jose'
+        josepy_path = 'josepy'
+    acme_jose_mod = importlib.import_module(acme_jose_path)
+    josepy_mod = importlib.import_module(josepy_path)
+
+    assert acme_jose_mod is josepy_mod
+    assert getattr(acme_jose_mod, attribute) is getattr(josepy_mod, attribute)
+
+    # We use the imports below with eval, but pylint doesn't
+    # understand that.
+    import josepy  # pylint: disable=unused-import
+
+    import acme  # pylint: disable=unused-import
+    acme_jose_mod = eval(acme_jose_path)  # pylint: disable=eval-used
+    josepy_mod = eval(josepy_path)  # pylint: disable=eval-used
+    assert acme_jose_mod is josepy_mod
+    assert getattr(acme_jose_mod, attribute) is getattr(josepy_mod, attribute)
+
+def test_top_level():
+    _test_it('', 'RS512')
+
+def test_submodules():
+    # This test ensures that the modules in josepy that were
+    # available at the time it was moved into its own package are
+    # available under acme.jose. Backwards compatibility with new
+    # modules or testing code is not maintained.
+    mods_and_attrs = [('b64', 'b64decode',),
+                      ('errors', 'Error',),
+                      ('interfaces', 'JSONDeSerializable',),
+                      ('json_util', 'Field',),
+                      ('jwa', 'HS256',),
+                      ('jwk', 'JWK',),
+                      ('jws', 'JWS',),
+                      ('util', 'ImmutableMap',),]
+
+    for mod, attr in mods_and_attrs:
+        _test_it(mod, attr)
 
 
 if __name__ == '__main__':

acme/tests/util_test.py

@@ -5,14 +5,11 @@
 import pytest
 
 
-class MapKeysTest(unittest.TestCase):
-    """Tests for acme.util.map_keys."""
-
-    def test_it(self):
-        from acme.util import map_keys
-        assert {'a': 'b', 'c': 'd'} == \
-                         map_keys({'a': 'b', 'c': 'd'}, lambda key: key)
-        assert {2: 2, 4: 4} == map_keys({1: 2, 3: 4}, lambda x: x + 1)
+def test_it():
+    from acme.util import map_keys
+    assert {'a': 'b', 'c': 'd'} == \
+                     map_keys({'a': 'b', 'c': 'd'}, lambda key: key)
+    assert {2: 2, 4: 4} == map_keys({1: 2, 3: 4}, lambda x: x + 1)
 
 
 if __name__ == '__main__':

certbot-apache/tests/entrypoint_test.py

@@ -1,6 +1,5 @@
 """Test for certbot_apache._internal.entrypoint for override class resolution"""
 import sys
-import unittest
 from unittest import mock
 
 import pytest
@@ -9,38 +8,34 @@
 from certbot_apache._internal import entrypoint
 
 
-class EntryPointTest(unittest.TestCase):
-    """Entrypoint tests"""
-
-    def test_get_configurator(self):
-
-        with mock.patch("certbot.util.get_os_info") as mock_info:
-            for distro in entrypoint.OVERRIDE_CLASSES:
-                return_value = (distro, "whatever")
-                if distro == 'fedora_old':
-                    return_value = ('fedora', '28')
-                elif distro == 'fedora':
-                    return_value = ('fedora', '29')
-                mock_info.return_value = return_value
-                assert entrypoint.get_configurator() == \
-                                 entrypoint.OVERRIDE_CLASSES[distro]
-
-    def test_nonexistent_like(self):
-        with mock.patch("certbot.util.get_os_info") as mock_info:
-            mock_info.return_value = ("nonexistent", "irrelevant")
-            with mock.patch("certbot.util.get_systemd_os_like") as mock_like:
-                for like in entrypoint.OVERRIDE_CLASSES:
-                    mock_like.return_value = [like]
-                    assert entrypoint.get_configurator() == \
-                                     entrypoint.OVERRIDE_CLASSES[like]
-
-    def test_nonexistent_generic(self):
-        with mock.patch("certbot.util.get_os_info") as mock_info:
-            mock_info.return_value = ("nonexistent", "irrelevant")
-            with mock.patch("certbot.util.get_systemd_os_like") as mock_like:
-                mock_like.return_value = ["unknown"]
+def test_get_configurator():
+    with mock.patch("certbot.util.get_os_info") as mock_info:
+        for distro in entrypoint.OVERRIDE_CLASSES:
+            return_value = (distro, "whatever")
+            if distro == 'fedora_old':
+                return_value = ('fedora', '28')
+            elif distro == 'fedora':
+                return_value = ('fedora', '29')
+            mock_info.return_value = return_value
+            assert entrypoint.get_configurator() == \
+                             entrypoint.OVERRIDE_CLASSES[distro]
+
+def test_nonexistent_like():
+    with mock.patch("certbot.util.get_os_info") as mock_info:
+        mock_info.return_value = ("nonexistent", "irrelevant")
+        with mock.patch("certbot.util.get_systemd_os_like") as mock_like:
+            for like in entrypoint.OVERRIDE_CLASSES:
+                mock_like.return_value = [like]
                 assert entrypoint.get_configurator() == \
-                                 configurator.ApacheConfigurator
+                                 entrypoint.OVERRIDE_CLASSES[like]
+
+def test_nonexistent_generic():
+    with mock.patch("certbot.util.get_os_info") as mock_info:
+        mock_info.return_value = ("nonexistent", "irrelevant")
+        with mock.patch("certbot.util.get_systemd_os_like") as mock_like:
+            mock_like.return_value = ["unknown"]
+            assert entrypoint.get_configurator() == \
+                             configurator.ApacheConfigurator
 
 
 if __name__ == "__main__":

certbot-apache/tests/parsernode_test.py

@@ -1,7 +1,6 @@
 """ Tests for ParserNode interface """
 
 import sys
-import unittest
 
 import pytest
 
@@ -104,27 +103,25 @@ def unsaved_files(self):  # pragma: no cover
 interfaces.DirectiveNode.register(DummyDirectiveNode)
 interfaces.BlockNode.register(DummyBlockNode)
 
-class ParserNodeTest(unittest.TestCase):
+def test_dummy():
     """Dummy placeholder test case for ParserNode interfaces"""
-
-    def test_dummy(self):
-        dummyblock = DummyBlockNode(
-            name="None",
-            parameters=(),
-            ancestor=None,
-            dirty=False,
-            filepath="/some/random/path"
-        )
-        dummydirective = DummyDirectiveNode(
-            name="Name",
-            ancestor=None,
-            filepath="/another/path"
-        )
-        dummycomment = DummyCommentNode(
-            comment="Comment",
-            ancestor=dummyblock,
-            filepath="/some/file"
-        )
+    dummyblock = DummyBlockNode(
+        name="None",
+        parameters=(),
+        ancestor=None,
+        dirty=False,
+        filepath="/some/random/path"
+    )
+    dummydirective = DummyDirectiveNode(
+        name="Name",
+        ancestor=None,
+        filepath="/another/path"
+    )
+    dummycomment = DummyCommentNode(
+        comment="Comment",
+        ancestor=dummyblock,
+        filepath="/some/file"
+    )
 
 
 if __name__ == "__main__":