From 3093175f544e9f976caada8d4dbe6dc2f99a0108 Mon Sep 17 00:00:00 2001
From: Matthieu Rigal <matt.rigal@gmail.com>
Date: Fri, 12 Jun 2015 11:03:52 +0200
Subject: [PATCH] SequenceField for abstract classes now have a proper name

---
 mongoengine/base/document.py    |  2 +-
 mongoengine/base/metaclasses.py |  1 -
 mongoengine/document.py         |  8 ++---
 mongoengine/fields.py           |  4 +--
 tests/fields/fields.py          | 52 +++++++++++++++++++++++++++++++++
 5 files changed, 59 insertions(+), 8 deletions(-)

diff --git a/mongoengine/base/document.py b/mongoengine/base/document.py
index 9357fde2..1049eabd 100644
--- a/mongoengine/base/document.py
+++ b/mongoengine/base/document.py
@@ -672,7 +672,7 @@ class BaseDocument(object):
 
     @classmethod
     def _get_collection_name(cls):
-        """Returns the collection name for this class.
+        """Returns the collection name for this class. None for abstract class
         """
         return cls._meta.get('collection', None)
 
diff --git a/mongoengine/base/metaclasses.py b/mongoengine/base/metaclasses.py
index 16e6bd29..d4c26bfe 100644
--- a/mongoengine/base/metaclasses.py
+++ b/mongoengine/base/metaclasses.py
@@ -424,7 +424,6 @@ class TopLevelDocumentMetaclass(DocumentMetaclass):
         return id_name, id_db_name
 
 
-
 class MetaDict(dict):
 
     """Custom dictionary for meta classes.
diff --git a/mongoengine/document.py b/mongoengine/document.py
index 7b05ef8c..885f7eed 100644
--- a/mongoengine/document.py
+++ b/mongoengine/document.py
@@ -145,7 +145,7 @@ class Document(BaseDocument):
     my_metaclass = TopLevelDocumentMetaclass
     __metaclass__ = TopLevelDocumentMetaclass
 
-    __slots__ = ('__objects')
+    __slots__ = ('__objects',)
 
     def pk():
         """Primary key alias
@@ -174,10 +174,10 @@ class Document(BaseDocument):
             db = cls._get_db()
             collection_name = cls._get_collection_name()
             # Create collection as a capped collection if specified
-            if cls._meta['max_size'] or cls._meta['max_documents']:
+            if cls._meta.get('max_size') or cls._meta.get('max_documents'):
                 # Get max document limit and max byte size from meta
-                max_size = cls._meta['max_size'] or 10000000  # 10MB default
-                max_documents = cls._meta['max_documents']
+                max_size = cls._meta.get('max_size') or 10000000  # 10MB default
+                max_documents = cls._meta.get('max_documents')
 
                 if collection_name in db.collection_names():
                     cls._collection = db[collection_name]
diff --git a/mongoengine/fields.py b/mongoengine/fields.py
index 9176828c..94f41d28 100644
--- a/mongoengine/fields.py
+++ b/mongoengine/fields.py
@@ -1694,7 +1694,7 @@ class SequenceField(BaseField):
         self.sequence_name = sequence_name
         self.value_decorator = (callable(value_decorator) and
                                 value_decorator or self.VALUE_DECORATOR)
-        return super(SequenceField, self).__init__(*args, **kwargs)
+        super(SequenceField, self).__init__(*args, **kwargs)
 
     def generate(self):
         """
@@ -1740,7 +1740,7 @@ class SequenceField(BaseField):
         if self.sequence_name:
             return self.sequence_name
         owner = self.owner_document
-        if issubclass(owner, Document):
+        if issubclass(owner, Document) and not owner._meta.get('abstract'):
             return owner._get_collection_name()
         else:
             return ''.join('_%s' % c if c.isupper() else c
diff --git a/tests/fields/fields.py b/tests/fields/fields.py
index fd083c73..9f9bf1dd 100644
--- a/tests/fields/fields.py
+++ b/tests/fields/fields.py
@@ -39,6 +39,7 @@ class FieldTest(unittest.TestCase):
     def tearDown(self):
         self.db.drop_collection('fs.files')
         self.db.drop_collection('fs.chunks')
+        self.db.drop_collection('mongoengine.counters')
 
     def test_default_values_nothing_set(self):
         """Ensure that default field values are used when creating a document.
@@ -2954,6 +2955,57 @@ class FieldTest(unittest.TestCase):
         self.assertEqual(1, post.comments[0].id)
         self.assertEqual(2, post.comments[1].id)
 
+    def test_inherited_sequencefield(self):
+        class Base(Document):
+            name = StringField()
+            counter = SequenceField()
+            meta = {'abstract': True}
+
+        class Foo(Base):
+            pass
+
+        class Bar(Base):
+            pass
+
+        bar = Bar(name='Bar')
+        bar.save()
+
+        foo = Foo(name='Foo')
+        foo.save()
+
+        self.assertTrue('base.counter' in
+                        self.db['mongoengine.counters'].find().distinct('_id'))
+        self.assertFalse(('foo.counter' or 'bar.counter') in
+                         self.db['mongoengine.counters'].find().distinct('_id'))
+        self.assertNotEqual(foo.counter, bar.counter)
+        self.assertEqual(foo._fields['counter'].owner_document, Base)
+        self.assertEqual(bar._fields['counter'].owner_document, Base)
+
+    def test_no_inherited_sequencefield(self):
+        class Base(Document):
+            name = StringField()
+            meta = {'abstract': True}
+
+        class Foo(Base):
+            counter = SequenceField()
+
+        class Bar(Base):
+            counter = SequenceField()
+
+        bar = Bar(name='Bar')
+        bar.save()
+
+        foo = Foo(name='Foo')
+        foo.save()
+
+        self.assertFalse('base.counter' in
+                         self.db['mongoengine.counters'].find().distinct('_id'))
+        self.assertTrue(('foo.counter' and 'bar.counter') in
+                         self.db['mongoengine.counters'].find().distinct('_id'))
+        self.assertEqual(foo.counter, bar.counter)
+        self.assertEqual(foo._fields['counter'].owner_document, Foo)
+        self.assertEqual(bar._fields['counter'].owner_document, Bar)
+
     def test_generic_embedded_document(self):
         class Car(EmbeddedDocument):
             name = StringField()