CXMAN-263: Add generic Dummy class infrastructure

Based on the python Mock framework. This will allow us to define
dummy classes that automatically track method calls, pass the
isinstance test, and raise AttributeError if we try to access
anything that wasn't defined in the original class.

3 files changed, 98 insertions, 2 deletions

diff --git a/cxmanage_api/dummies/__init__.py b/cxmanage_api/dummies/__init__.py
new file mode 100644
index 0000000..856b92b
--- /dev/null
+++ b/cxmanage_api/dummies/__init__.py
@@ -0,0 +1,31 @@
+# Copyright (c) 2012-2013, Calxeda Inc.
+#
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+# * Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+# * Neither the name of Calxeda Inc. nor the names of its contributors
+# may be used to endorse or promote products derived from this software
+# without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+# TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+# THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+# DAMAGE.
+
+from cxmanage_api.dummies.dummy import Dummy
diff --git a/cxmanage_api/dummies/dummy.py b/cxmanage_api/dummies/dummy.py
new file mode 100644
index 0000000..baf8470
--- /dev/null
+++ b/cxmanage_api/dummies/dummy.py
@@ -0,0 +1,63 @@
+# Copyright (c) 2012-2013, Calxeda Inc.
+#
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+# * Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+# * Neither the name of Calxeda Inc. nor the names of its contributors
+# may be used to endorse or promote products derived from this software
+# without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+# TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+# THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+# DAMAGE.
+
+from mock import Mock
+
+
+def Dummy(spec):
+    """ Returns a dummy that behaves like the specified class.
+
+    The returned value is a Class, not an Instance, so it can be subclassed.
+
+    By default, any attribute accessed in an instance will be equal to None.
+    Return values, or other side effects, can be defined by overriding the
+    functions/properties in a subclass.
+
+    """
+    class SpeccedDummy(object):
+        """ Specced dummy class. Instantiating this actually gives us a Mock
+        object, defined by spec, that wraps ourselves.
+
+        """
+        def __new__(cls, *args, **kwargs):
+            self = super(SpeccedDummy, cls).__new__(cls, *args, **kwargs)
+            self.__init__(*args, **kwargs)
+            return Mock(spec=spec, wraps=self, name=cls.__name__)
+
+        def __getattr__(self, name):
+            """ Return None for any undefined attributes.
+
+            This is necessary to allow for attributes that are found in the
+            spec, but not defined in any subclass of SpeccedDummy.
+
+            """
+            return None
+
+    return SpeccedDummy
diff --git a/setup.py b/setup.py
index 52da8cc..fb8eedc 100644
--- a/setup.py
+++ b/setup.py
@@ -49,7 +49,8 @@ setup(
         'cxmanage_api',
         'cxmanage_api.cli',
         'cxmanage_api.cli.commands',
-        'cxmanage_api.tests'
+        'cxmanage_api.tests',
+        'cxmanage_api.dummies'
     ],
     scripts=['scripts/cxmanage', 'scripts/sol_tabs', 'scripts/cxmux'],
     description='Calxeda Management Utility',
@@ -60,7 +61,8 @@ setup(
                         'pexpect',
                         'pyipmi>=0.9.1',
                         'argparse',
-                        'unittest-xml-reporting'
+                        'unittest-xml-reporting',
+                        'mock'
     ],
     extras_require={
         'docs': ['sphinx', 'cloud_sptheme'],