pass on @abc.abstractmethods

Although a bare docstring is entirely valid grammar, those new to Python find
that pattern baffling, *especially* when other similar methods contain pass
statements. So, for consistency, add a pass statement to otherwise bare
@abc.abstractmethods.

Note that the implementation of an @abc.abstractmethod (in the abstract
base class) can still be called by concrete children, so suddenly
raising a NotImplementedError() instead might be "surprising" to
implementors. A no-op such as "pass" or "return None" is preferable.

Change-Id: I79969ad1a3429516ea785c649a165ead54944225

keystoneclient/auth/identity/base.py

@@ -184,6 +184,7 @@ class BaseIdentityPlugin(base.BaseAuthPlugin):
         :returns: Token access information.
         :rtype: :py:class:`keystoneclient.access.AccessInfo`
         """
+        pass
 
     def get_token(self, session, **kwargs):
         """Return a valid auth token.

keystoneclient/auth/identity/v2.py

@@ -103,6 +103,7 @@ class Auth(base.BaseIdentityPlugin):
         :return: A dict of authentication data for the auth type.
         :rtype: dict
         """
+        pass
 
 
 _NOT_PASSED = object()

keystoneclient/auth/identity/v3/base.py

@@ -240,6 +240,7 @@ class AuthMethod(object):
                  data for the auth type.
         :rtype: tuple(string, dict)
         """
+        pass
 
 
 @six.add_metaclass(abc.ABCMeta)

keystoneclient/openstack/common/apiclient/auth.py

@@ -204,8 +204,8 @@ class BaseAuthPlugin(object):
 
     @abc.abstractmethod
     def _do_authenticate(self, http_client):
-        """Protected method for authentication.
-        """
+        """Protected method for authentication."""
+        pass
 
     def sufficient_options(self):
         """Check if all required options are present.
@@ -232,3 +232,4 @@ class BaseAuthPlugin(object):
         :returns: tuple of token and endpoint strings
         :raises: EndpointException
         """
+        pass

keystoneclient/service_catalog.py

@@ -110,6 +110,7 @@ class ServiceCatalog(object):
         :returns: True if the provided endpoint matches the required
         endpoint_type otherwise False.
         """
+        pass
 
     @abc.abstractmethod
     def _normalize_endpoint_type(self, endpoint_type):
@@ -122,6 +123,7 @@ class ServiceCatalog(object):
         :returns: the endpoint string in the format appropriate for this
                   service catalog.
         """
+        pass
 
     def get_endpoints(self, service_type=None, endpoint_type=None,
                       region_name=None, service_name=None):

keystoneclient/tests/unit/auth/test_identity_common.py

@@ -55,6 +55,7 @@ class CommonIdentityTests(object):
         It doesn't really matter what auth mechanism is used but it should be
         appropriate to the API version.
         """
+        pass
 
     @abc.abstractmethod
     def get_auth_data(self, **kwargs):
@@ -63,6 +64,7 @@ class CommonIdentityTests(object):
         This should register a valid token response and ensure that the compute
         endpoints are set to TEST_COMPUTE_PUBLIC, _INTERNAL and _ADMIN.
         """
+        pass
 
     def stub_auth_data(self, **kwargs):
         token = self.get_auth_data(**kwargs)