Move common libs to libs/common

libs/common/stevedore/tests/test_driver.py

@@ -0,0 +1,89 @@
+#  Licensed under the Apache License, Version 2.0 (the "License"); you may
+#  not use this file except in compliance with the License. You may obtain
+#  a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#  License for the specific language governing permissions and limitations
+#  under the License.
+
+"""Tests for stevedore.extension
+"""
+
+import pkg_resources
+
+from stevedore import driver
+from stevedore import exception
+from stevedore import extension
+from stevedore.tests import test_extension
+from stevedore.tests import utils
+
+
+class TestCallback(utils.TestCase):
+    def test_detect_plugins(self):
+        em = driver.DriverManager('stevedore.test.extension', 't1')
+        names = sorted(em.names())
+        self.assertEqual(names, ['t1'])
+
+    def test_call(self):
+        def invoke(ext, *args, **kwds):
+            return (ext.name, args, kwds)
+        em = driver.DriverManager('stevedore.test.extension', 't1')
+        result = em(invoke, 'a', b='C')
+        self.assertEqual(result, ('t1', ('a',), {'b': 'C'}))
+
+    def test_driver_property_not_invoked_on_load(self):
+        em = driver.DriverManager('stevedore.test.extension', 't1',
+                                  invoke_on_load=False)
+        d = em.driver
+        self.assertIs(d, test_extension.FauxExtension)
+
+    def test_driver_property_invoked_on_load(self):
+        em = driver.DriverManager('stevedore.test.extension', 't1',
+                                  invoke_on_load=True)
+        d = em.driver
+        self.assertIsInstance(d, test_extension.FauxExtension)
+
+    def test_no_drivers(self):
+        try:
+            driver.DriverManager('stevedore.test.extension.none', 't1')
+        except exception.NoMatches as err:
+            self.assertIn("No 'stevedore.test.extension.none' driver found",
+                          str(err))
+
+    def test_bad_driver(self):
+        try:
+            driver.DriverManager('stevedore.test.extension', 'e2')
+        except ImportError:
+            pass
+        else:
+            self.assertEqual(False, "No error raised")
+
+    def test_multiple_drivers(self):
+        # The idea for this test was contributed by clayg:
+        # https://gist.github.com/clayg/6311348
+        extensions = [
+            extension.Extension(
+                'backend',
+                pkg_resources.EntryPoint.parse('backend = pkg1:driver'),
+                'pkg backend',
+                None,
+            ),
+            extension.Extension(
+                'backend',
+                pkg_resources.EntryPoint.parse('backend = pkg2:driver'),
+                'pkg backend',
+                None,
+            ),
+        ]
+        try:
+            dm = driver.DriverManager.make_test_instance(extensions[0])
+            # Call the initialization code that verifies the extension
+            dm._init_plugins(extensions)
+        except exception.MultipleMatches as err:
+            self.assertIn("Multiple", str(err))
+        else:
+            self.fail('Should have had an error')