From 4209d61b1368717047927cee40a9d64768def93a Mon Sep 17 00:00:00 2001
From: Ross Lawley <ross.lawley@gmail.com>
Date: Wed, 10 Jul 2013 12:49:19 +0000
Subject: [PATCH] Document.select_related() now respects `db_alias` (#377)

---
 docs/changelog.rst        |  1 +
 mongoengine/document.py   |  4 ++--
 tests/fields/fields.py    | 31 +++++++++++++++++++++++++++
 tests/test_dereference.py | 45 +++++++++++++++++----------------------
 4 files changed, 54 insertions(+), 27 deletions(-)

diff --git a/docs/changelog.rst b/docs/changelog.rst
index 42fd9bb1..926c6cb1 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -4,6 +4,7 @@ Changelog
 
 Changes in 0.8.3
 ================
+- Document.select_related() now respects `db_alias` (#377)
 - Reload uses shard_key if applicable (#384)
 - Dynamic fields are ordered based on creation and stored in _fields_ordered (#396)
 - Fixed pickling dynamic documents `_dynamic_fields` (#387)
diff --git a/mongoengine/document.py b/mongoengine/document.py
index c9901a2a..e331aa1f 100644
--- a/mongoengine/document.py
+++ b/mongoengine/document.py
@@ -440,8 +440,8 @@ class Document(BaseDocument):
 
         .. versionadded:: 0.5
         """
-        import dereference
-        self._data = dereference.DeReference()(self._data, max_depth)
+        DeReference = _import_class('DeReference')
+        DeReference()([self], max_depth + 1)
         return self
 
     def reload(self, max_depth=1):
diff --git a/tests/fields/fields.py b/tests/fields/fields.py
index 8f024991..b3d8d52e 100644
--- a/tests/fields/fields.py
+++ b/tests/fields/fields.py
@@ -2474,6 +2474,37 @@ class FieldTest(unittest.TestCase):
         user = User(email='me@example.com')
         self.assertTrue(user.validate() is None)
 
+    def test_tuples_as_tuples(self):
+        """
+        Ensure that tuples remain tuples when they are
+        inside a ComplexBaseField
+        """
+        from mongoengine.base import BaseField
+
+        class EnumField(BaseField):
+
+            def __init__(self, **kwargs):
+                super(EnumField, self).__init__(**kwargs)
+
+            def to_mongo(self, value):
+                return value
+
+            def to_python(self, value):
+                return tuple(value)
+
+        class TestDoc(Document):
+            items = ListField(EnumField())
+
+        TestDoc.drop_collection()
+        tuples = [(100, 'Testing')]
+        doc = TestDoc()
+        doc.items = tuples
+        doc.save()
+        x = TestDoc.objects().get()
+        self.assertTrue(x is not None)
+        self.assertTrue(len(x.items) == 1)
+        self.assertTrue(tuple(x.items[0]) in tuples)
+        self.assertTrue(x.items[0] in tuples)
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/tests/test_dereference.py b/tests/test_dereference.py
index e146963f..db9868a0 100644
--- a/tests/test_dereference.py
+++ b/tests/test_dereference.py
@@ -1121,37 +1121,32 @@ class FieldTest(unittest.TestCase):
 
             self.assertEqual(q, 2)
 
-    def test_tuples_as_tuples(self):
-        """
-        Ensure that tuples remain tuples when they are
-        inside a ComplexBaseField
-        """
-        from mongoengine.base import BaseField
+    def test_objectid_reference_across_databases(self):
+        # mongoenginetest - Is default connection alias from setUp()
+        # Register Aliases
+        register_connection('testdb-1', 'mongoenginetest2')
 
-        class EnumField(BaseField):
+        class User(Document):
+            name = StringField()
+            meta = {"db_alias": "testdb-1"}
 
-            def __init__(self, **kwargs):
-                super(EnumField, self).__init__(**kwargs)
+        class Book(Document):
+            name = StringField()
+            author = ReferenceField(User)
 
-            def to_mongo(self, value):
-                return value
+        # Drops
+        User.drop_collection()
+        Book.drop_collection()
 
-            def to_python(self, value):
-                return tuple(value)
+        user = User(name="Ross").save()
+        Book(name="MongoEngine for pros", author=user).save()
 
-        class TestDoc(Document):
-            items = ListField(EnumField())
+        # Can't use query_counter across databases - so test the _data object
+        book = Book.objects.first()
+        self.assertFalse(isinstance(book._data['author'], User))
 
-        TestDoc.drop_collection()
-        tuples = [(100, 'Testing')]
-        doc = TestDoc()
-        doc.items = tuples
-        doc.save()
-        x = TestDoc.objects().get()
-        self.assertTrue(x is not None)
-        self.assertTrue(len(x.items) == 1)
-        self.assertTrue(tuple(x.items[0]) in tuples)
-        self.assertTrue(x.items[0] in tuples)
+        book.select_related()
+        self.assertTrue(isinstance(book._data['author'], User))
 
     def test_non_ascii_pk(self):
         """