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diff --git a/appengine_django/tests/serialization_test.py b/appengine_django/tests/serialization_test.py
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+++ b/appengine_django/tests/serialization_test.py
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+#!/usr/bin/python2.4
+#
+# Copyright 2008 Google Inc.
+#
+# 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 that the serialization modules are functioning correctly.
+
+In particular, these tests verify that the modifications made to the standard
+Django serialization modules function correctly and that the combined datastore
+and Django models can be dumped and loaded to all of the provided formats.
+"""
+
+
+import os
+import re
+import unittest
+from StringIO import StringIO
+
+from django.core import serializers
+
+from google.appengine.ext import db
+from appengine_django.models import BaseModel
+
+
+class ModelA(BaseModel):
+  description = db.StringProperty()
+
+
+class ModelB(BaseModel):
+  description = db.StringProperty()
+  friend = db.Reference(ModelA)
+
+
+class TestAllFormats(type):
+
+  def __new__(cls, name, bases, attrs):
+    """Extends base test functions to be called for every serialisation format.
+
+    Looks for functions matching 'run.*Test', where the wildcard in the middle
+    matches the desired test name and ensures that a test case is setup to call
+    that function once for every defined serialisation format. The test case
+    that is created will be called 'test<format><name>'. Eg, for the function
+    'runKeyedObjectTest' functions like 'testJsonKeyedObject' will be created.
+    """
+    test_formats = serializers.get_serializer_formats()
+    test_formats.remove("python")  # Python serializer is only used indirectly.
+
+    for func_name in attrs.keys():
+      m = re.match("^run(.*)Test$", func_name)
+      if not m:
+        continue
+      for format in test_formats:
+        test_name = "test%s%s" % (format.title(), m.group(1))
+        test_func = eval("lambda self: getattr(self, \"%s\")(\"%s\")" %
+                         (func_name, format))
+        attrs[test_name] = test_func
+
+    return super(TestAllFormats, cls).__new__(cls, name, bases, attrs)
+
+
+class SerializationTest(unittest.TestCase):
+  """Unit tests for the serialization/deserialization functionality.
+
+  Tests that every loaded serialization format can successfully dump and then
+  reload objects without the objects changing.
+  """
+  __metaclass__ = TestAllFormats
+
+  def compareObjects(self, orig, new, format="unknown"):
+    """Compares two objects to ensure they are identical.
+
+    Args:
+      orig: The original object, must be an instance of db.Model.
+      new: The new object, must be an instance of db.Model.
+      format: The serialization format being tested, used to make error output
+        more helpful.
+
+    Raises:
+      The function has no return value, but will raise assertion errors if the
+      objects do not match correctly.
+    """
+    if orig.key().name():
+      # Only compare object keys when the key is named. Key IDs are not static
+      # and will change between dump/load. If you want stable Keys they need to
+      # be named!
+      self.assertEqual(orig.key(), new.key(),
+                       "keys not equal after %s serialization: %s != %s" %
+                       (format, repr(orig.key()), repr(new.key())))
+
+    for key in orig.properties().keys():
+      oval = getattr(orig, key)
+      nval = getattr(new, key)
+      if isinstance(orig.properties()[key], db.Reference):
+        # Need to compare object keys not the objects themselves.
+        oval = oval.key()
+        nval = nval.key()
+      self.assertEqual(oval, nval, "%s attribute differs after %s "
+                       "serialization: %s != %s" % (key, format, oval, nval))
+
+  def doSerialisationTest(self, format, obj, rel_attr=None, obj_ref=None):
+    """Runs a serialization test on an object for the specified format.
+
+    Args:
+      format: The name of the Django serialization class to use.
+      obj: The object to {,de}serialize, must be an instance of db.Model.
+      rel_attr: Name of the attribute of obj references another model.
+      obj_ref: The expected object reference, must be an instance of db.Model.
+
+    Raises:
+      The function has no return value but raises assertion errors if the
+      object cannot be successfully serialized and then deserialized back to an
+      identical object. If rel_attr and obj_ref are specified the deserialized
+      object must also retain the references from the original object.
+    """
+    serialised = serializers.serialize(format, [obj])
+    # Try and get the object back from the serialized string.
+    result = list(serializers.deserialize(format, StringIO(serialised)))
+    self.assertEqual(1, len(result),
+                     "%s serialization should create 1 object" % format)
+    result[0].save()  # Must save back into the database to get a Key.
+    self.compareObjects(obj, result[0].object, format)
+    if rel_attr and obj_ref:
+      rel = getattr(result[0].object, rel_attr)
+      if callable(rel):
+        rel = rel()
+      self.compareObjects(rel, obj_ref, format)
+
+  def doLookupDeserialisationReferenceTest(self, lookup_dict, format):
+    """Tests the Key reference is loaded OK for a format.
+
+    Args:
+      lookup_dict: A dictionary indexed by format containing serialized strings
+        of the objects to load.
+      format: The format to extract from the dict and deserialize.
+
+    Raises:
+      This function has no return value but raises assertion errors if the
+      string cannot be deserialized correctly or the resulting object does not
+      reference the object correctly.
+    """
+    if format not in lookup_dict:
+      # Check not valid for this format.
+      return
+    obj = ModelA(description="test object", key_name="test")
+    obj.put()
+    s = lookup_dict[format]
+    result = list(serializers.deserialize(format, StringIO(s)))
+    self.assertEqual(1, len(result), "expected 1 object from %s" % format)
+    result[0].save()
+    self.compareObjects(obj, result[0].object.friend, format)
+
+  def doModelKeyDeserialisationReferenceTest(self, lookup_dict, format):
+    """Tests a model with a key can be loaded OK for a format.
+
+    Args:
+      lookup_dict: A dictionary indexed by format containing serialized strings
+        of the objects to load.
+      format: The format to extract from the dict and deserialize.
+
+    Returns:
+      This function has no return value but raises assertion errors if the
+      string cannot be deserialized correctly or the resulting object is not an
+      instance of ModelA with a key named 'test'.
+    """
+    if format not in lookup_dict:
+      # Check not valid for this format.
+      return
+    s = lookup_dict[format]
+    result = list(serializers.deserialize(format, StringIO(s)))
+    self.assertEqual(1, len(result), "expected 1 object from %s" % format)
+    result[0].save()
+    self.assert_(isinstance(result[0].object, ModelA))
+    self.assertEqual("test", result[0].object.key().name())
+
+  # Lookup dicts for the above (doLookupDeserialisationReferenceTest) function.
+  SERIALIZED_WITH_KEY_AS_LIST = {
+      "json": """[{"pk": "agR0ZXN0chMLEgZNb2RlbEIiB21vZGVsYmkM", """
+              """"model": "tests.modelb", "fields": {"description": "test", """
+              """"friend": ["ModelA", "test"] }}]""",
+      "yaml": """- fields: {description: !!python/unicode 'test', friend: """
+              """ [ModelA, test]}\n  model: tests.modelb\n  pk: """
+              """ agR0ZXN0chMLEgZNb2RlbEEiB21vZGVsYWkM\n"""
+  }
+  SERIALIZED_WITH_KEY_REPR = {
+      "json": """[{"pk": "agR0ZXN0chMLEgZNb2RlbEIiB21vZGVsYmkM", """
+              """"model": "tests.modelb", "fields": {"description": "test", """
+              """"friend": "datastore_types.Key.from_path("""
+              """'ModelA', 'test')" }}]""",
+      "yaml": """- fields: {description: !!python/unicode 'test', friend: """
+              """\'datastore_types.Key.from_path("ModelA", "test")\'}\n  """
+              """model: tests.modelb\n  pk: """
+              """ agR0ZXN0chMLEgZNb2RlbEEiB21vZGVsYWkM\n"""
+  }
+
+  # Lookup dict for the doModelKeyDeserialisationReferenceTest function.
+  MK_SERIALIZED_WITH_LIST = {
+      "json": """[{"pk": ["ModelA", "test"], "model": "tests.modela", """
+              """"fields": {}}]""",
+      "yaml": """-\n fields: {description: null}\n model: tests.modela\n """
+              """pk: [ModelA, test]\n"""
+  }
+  MK_SERIALIZED_WITH_KEY_REPR = {
+      "json": """[{"pk": "datastore_types.Key.from_path('ModelA', 'test')", """
+              """"model": "tests.modela", "fields": {}}]""",
+      "yaml": """-\n fields: {description: null}\n model: tests.modela\n """
+              """pk: \'datastore_types.Key.from_path("ModelA", "test")\'\n"""
+  }
+  MK_SERIALIZED_WITH_KEY_AS_TEXT = {
+      "json": """[{"pk": "test", "model": "tests.modela", "fields": {}}]""",
+      "yaml": """-\n fields: {description: null}\n model: tests.modela\n """
+              """pk: test\n"""
+  }
+
+  # Lookup dict for the function.
+  SERIALIZED_WITH_NON_EXISTANT_PARENT = {
+      "json": """[{"pk": "ahhnb29nbGUtYXBwLWVuZ2luZS1kamFuZ29yIgsSBk1vZG"""
+              """VsQiIGcGFyZW50DAsSBk1vZGVsQSIEdGVzdAw", """
+              """"model": "tests.modela", "fields": """
+              """{"description": null}}]""",
+      "yaml": """- fields: {description: null}\n  """
+              """model: tests.modela\n  """
+              """pk: ahhnb29nbGUtYXBwLWVuZ2luZS1kamFuZ29yIgsSBk1"""
+              """vZGVsQiIGcGFyZW50DAsSBk1vZGVsQSIEdGVzdAw\n""",
+      "xml":  """<?xml version="1.0" encoding="utf-8"?>\n"""
+              """<django-objects version="1.0">\n"""
+              """<entity kind="tests.modela" key="ahhnb29nbGUtYXBwL"""
+              """WVuZ2luZS1kamFuZ29yIgsSBk1vZGVsQiIGcGFyZW50DA"""
+              """sSBk1vZGVsQSIEdGVzdAw">\n  """
+              """<key>tag:google-app-engine-django.gmail.com,"""
+              """2008-05-13:ModelA[ahhnb29nbGUtYXBwLWVuZ2luZS1kam"""
+              """FuZ29yIgsSBk1vZGVsQiIGcGFyZW50DAsSBk1vZGVsQSIEdGVzdAw"""
+              """]</key>\n  <property name="description" """
+              """type="null"></property>\n</entity>\n</django-objects>"""
+  }
+
+  # The following functions are all expanded by the metaclass to be run once
+  # for every registered Django serialization module.
+
+  def runKeyedObjectTest(self, format):
+    """Test serialization of a basic object with a named key."""
+    obj = ModelA(description="test object", key_name="test")
+    obj.put()
+    self.doSerialisationTest(format, obj)
+
+  def runObjectWithIdTest(self, format):
+    """Test serialization of a basic object with a numeric ID key."""
+    obj = ModelA(description="test object")
+    obj.put()
+    self.doSerialisationTest(format, obj)
+
+  def runObjectWithReferenceTest(self, format):
+    """Test serialization of an object that references another object."""
+    obj = ModelA(description="test object", key_name="test")
+    obj.put()
+    obj2 = ModelB(description="friend object", friend=obj)
+    obj2.put()
+    self.doSerialisationTest(format, obj2, "friend", obj)
+
+  def runObjectWithParentTest(self, format):
+    """Test serialization of an object that has a parent object reference."""
+    obj = ModelA(description="parent object", key_name="parent")
+    obj.put()
+    obj2 = ModelA(description="child object", key_name="child", parent=obj)
+    obj2.put()
+    self.doSerialisationTest(format, obj2, "parent", obj)
+
+  def runObjectWithNonExistantParentTest(self, format):
+    """Test deserialization of an object referencing a non-existant parent."""
+    self.doModelKeyDeserialisationReferenceTest(
+        self.SERIALIZED_WITH_NON_EXISTANT_PARENT, format)
+
+  def runCreateKeyReferenceFromListTest(self, format):
+    """Tests that a reference specified as a list in json/yaml can be loaded OK."""
+    self.doLookupDeserialisationReferenceTest(self.SERIALIZED_WITH_KEY_AS_LIST,
+                                              format)
+
+  def runCreateKeyReferenceFromReprTest(self, format):
+    """Tests that a reference specified as repr(Key) in can loaded OK."""
+    self.doLookupDeserialisationReferenceTest(self.SERIALIZED_WITH_KEY_REPR,
+                                              format)
+
+  def runCreateModelKeyFromListTest(self, format):
+    """Tests that a model key specified as a list can be loaded OK."""
+    self.doModelKeyDeserialisationReferenceTest(self.MK_SERIALIZED_WITH_LIST,
+                                                format)
+
+  def runCreateModelKeyFromReprTest(self, format):
+    """Tests that a model key specified as a repr(Key) can be loaded OK."""
+    self.doModelKeyDeserialisationReferenceTest(
+        self.MK_SERIALIZED_WITH_KEY_REPR, format)
+
+  def runCreateModelKeyFromTextTest(self, format):
+    """Tests that a reference specified as a plain key_name loads OK."""
+    self.doModelKeyDeserialisationReferenceTest(
+        self.MK_SERIALIZED_WITH_KEY_AS_TEXT, format)
+
+
+if __name__ == '__main__':
+  unittest.main()