Revert "add tests to increase code coverage"

add tests to increase code coverage

.install_mongodb_on_travis.sh

@@ -1,5 +1,6 @@
 #!/bin/bash
 
+sudo apt-get remove mongodb-org-server
 sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 7F0CEB10
 
 if [ "$MONGODB" = "2.4" ]; then
@@ -13,7 +14,7 @@ elif [ "$MONGODB" = "2.6" ]; then
     sudo apt-get install mongodb-org-server=2.6.12
     # service should be started automatically
 elif [ "$MONGODB" = "3.0" ]; then
-    echo "deb http://repo.mongodb.org/apt/ubuntu precise/mongodb-org/3.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb.list
+    echo "deb http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb.list
     sudo apt-get update
     sudo apt-get install mongodb-org-server=3.0.14
     # service should be started automatically
@@ -21,3 +22,6 @@ else
     echo "Invalid MongoDB version, expected 2.4, 2.6, or 3.0."
     exit 1
 fi;
+
+mkdir db
+1>db/logs mongod --dbpath=db &

.travis.yml

@@ -15,6 +15,7 @@ language: python
 python:
 - 2.7
 - 3.5
+- 3.6
 - pypy
 
 env:
@@ -39,9 +40,15 @@ matrix:
     env: MONGODB=2.4 PYMONGO=3.0
   - python: 3.5
     env: MONGODB=3.0 PYMONGO=3.0
+  - python: 3.6
+    env: MONGODB=2.4 PYMONGO=3.0
+  - python: 3.6
+    env: MONGODB=3.0 PYMONGO=3.0
 
 before_install:
 - bash .install_mongodb_on_travis.sh
+- sleep 15  # https://docs.travis-ci.com/user/database-setup/#MongoDB-does-not-immediately-accept-connections
+- mongo --eval 'db.version();'
 
 install:
 - sudo apt-get install python-dev python3-dev libopenjpeg-dev zlib1g-dev libjpeg-turbo8-dev
@@ -90,7 +97,7 @@ deploy:
   distributions: "sdist bdist_wheel"
 
   # only deploy on tagged commits (aka GitHub releases) and only for the
-  # parent repo's builds running Python 2.7 along with dev PyMongo (we run
+  # parent repo's builds running Python 2.7 along with PyMongo v3.0 (we run
   # Travis against many different Python and PyMongo versions and we don't
   # want the deploy to occur multiple times).
   on:

AUTHORS

@@ -243,3 +243,5 @@ that much better:
  * Victor Varvaryuk
  * Stanislav Kaledin (https://github.com/sallyruthstruik)
  * Dmitry Yantsen (https://github.com/mrTable)
+ * Renjianxin (https://github.com/Davidrjx)
+ * Erdenezul Batmunkh (https://github.com/erdenezul)

docs/changelog.rst

@@ -2,9 +2,24 @@
 Changelog
 =========
 
-Development
+dev
-===========
+===
-- (Fill this out as you fix issues and develop your features).
+-  Subfield resolve error in generic_emdedded_document query #1651 #1652
+-  use each modifier only with $position #1673 #1675
+-  Improve LazyReferenceField and GenericLazyReferenceField with nested fields #1704
+-  Fix validation error instance in GenericEmbeddedDocumentField #1067
+
+Changes in 0.15.0
+=================
+- Add LazyReferenceField and GenericLazyReferenceField to address #1230
+
+Changes in 0.14.1
+=================
+- Removed SemiStrictDict and started using a regular dict for `BaseDocument._data` #1630
+- Added support for the `$position` param in the `$push` operator #1566
+- Fixed `DateTimeField` interpreting an empty string as today #1533
+- Added a missing `__ne__` method to the `GridFSProxy` class #1632
+- Fixed `BaseQuerySet._fields_to_db_fields` #1553
 
 Changes in 0.14.0
 =================

docs/guide/querying.rst

@@ -565,6 +565,15 @@ cannot use the `$` syntax in keyword arguments it has been mapped to `S`::
     >>> post.tags
     ['database', 'mongodb']
 
+From MongoDB version 2.6, push operator supports $position value which allows
+to push values with index.
+    >>> post = BlogPost(title="Test", tags=["mongo"])
+    >>> post.save()
+    >>> post.update(push__tags__0=["database", "code"])
+    >>> post.reload()
+    >>> post.tags
+    ['database', 'code', 'mongo']
+
 .. note::
     Currently only top level lists are handled, future versions of mongodb /
     pymongo plan to support nested positional operators.  See `The $ positional

docs/tutorial.rst

@@ -153,7 +153,7 @@ post. This works, but there is no real reason to be storing the comments
 separately from their associated posts, other than to work around the
 relational model. Using MongoDB we can store the comments as a list of
 *embedded documents* directly on a post document. An embedded document should
-be treated no differently that a regular document; it just doesn't have its own
+be treated no differently than a regular document; it just doesn't have its own
 collection in the database. Using MongoEngine, we can define the structure of
 embedded documents, along with utility methods, in exactly the same way we do
 with regular documents::

mongoengine/__init__.py

@@ -23,7 +23,7 @@ __all__ = (list(document.__all__) + list(fields.__all__) +
            list(signals.__all__) + list(errors.__all__))
 
 
-VERSION = (0, 14, 0)
+VERSION = (0, 15, 0)
 
 
 def get_version():

mongoengine/base/__init__.py

@@ -15,7 +15,7 @@ __all__ = (
     'UPDATE_OPERATORS', '_document_registry', 'get_document',
 
     # datastructures
-    'BaseDict', 'BaseList', 'EmbeddedDocumentList',
+    'BaseDict', 'BaseList', 'EmbeddedDocumentList', 'LazyReference',
 
     # document
     'BaseDocument',

mongoengine/base/datastructures.py

@@ -1,12 +1,13 @@
 import itertools
 import weakref
 
+from bson import DBRef
 import six
 
 from mongoengine.common import _import_class
 from mongoengine.errors import DoesNotExist, MultipleObjectsReturned
 
-__all__ = ('BaseDict', 'BaseList', 'EmbeddedDocumentList')
+__all__ = ('BaseDict', 'BaseList', 'EmbeddedDocumentList', 'LazyReference')
 
 
 class BaseDict(dict):
@@ -127,7 +128,7 @@ class BaseList(list):
         return value
 
     def __iter__(self):
-        for i in xrange(self.__len__()):
+        for i in six.moves.range(self.__len__()):
             yield self[i]
 
     def __setitem__(self, key, value, *args, **kwargs):
@@ -447,40 +448,40 @@ class StrictDict(object):
         return cls._classes[allowed_keys]
 
 
-class SemiStrictDict(StrictDict):
+class LazyReference(DBRef):
-    __slots__ = ('_extras', )
+    __slots__ = ('_cached_doc', 'passthrough', 'document_type')
-    _classes = {}
 
-    def __getattr__(self, attr):
+    def fetch(self, force=False):
-        try:
+        if not self._cached_doc or force:
-            super(SemiStrictDict, self).__getattr__(attr)
+            self._cached_doc = self.document_type.objects.get(pk=self.pk)
-        except AttributeError:
+            if not self._cached_doc:
-            try:
+                raise DoesNotExist('Trying to dereference unknown document %s' % (self))
-                return self.__getattribute__('_extras')[attr]
+        return self._cached_doc
-            except KeyError as e:
-                raise AttributeError(e)
 
-    def __setattr__(self, attr, value):
+    @property
-        try:
+    def pk(self):
-            super(SemiStrictDict, self).__setattr__(attr, value)
+        return self.id
-        except AttributeError:
-            try:
-                self._extras[attr] = value
-            except AttributeError:
-                self._extras = {attr: value}
 
-    def __delattr__(self, attr):
+    def __init__(self, document_type, pk, cached_doc=None, passthrough=False):
-        try:
+        self.document_type = document_type
-            super(SemiStrictDict, self).__delattr__(attr)
+        self._cached_doc = cached_doc
-        except AttributeError:
+        self.passthrough = passthrough
-            try:
+        super(LazyReference, self).__init__(self.document_type._get_collection_name(), pk)
-                del self._extras[attr]
-            except KeyError as e:
-                raise AttributeError(e)
 
-    def __iter__(self):
+    def __getitem__(self, name):
+        if not self.passthrough:
+            raise KeyError()
+        document = self.fetch()
+        return document[name]
+
+    def __getattr__(self, name):
+        if not object.__getattribute__(self, 'passthrough'):
+            raise AttributeError()
+        document = self.fetch()
         try:
-            extras_iter = iter(self.__getattribute__('_extras'))
+            return document[name]
-        except AttributeError:
+        except KeyError:
-            extras_iter = ()
+            raise AttributeError()
-        return itertools.chain(super(SemiStrictDict, self).__iter__(), extras_iter)
+
+    def __repr__(self):
+        return "<LazyReference(%s, %r)>" % (self.document_type, self.pk)

mongoengine/base/document.py

@@ -13,13 +13,14 @@ from mongoengine import signals
 from mongoengine.base.common import get_document
 from mongoengine.base.datastructures import (BaseDict, BaseList,
                                              EmbeddedDocumentList,
-                                             SemiStrictDict, StrictDict)
+                                             LazyReference,
+                                             StrictDict)
 from mongoengine.base.fields import ComplexBaseField
 from mongoengine.common import _import_class
 from mongoengine.errors import (FieldDoesNotExist, InvalidDocumentError,
                                 LookUpError, OperationError, ValidationError)
 
-__all__ = ('BaseDocument',)
+__all__ = ('BaseDocument', 'NON_FIELD_ERRORS')
 
 NON_FIELD_ERRORS = '__all__'
 
@@ -79,8 +80,7 @@ class BaseDocument(object):
         if self.STRICT and not self._dynamic:
             self._data = StrictDict.create(allowed_keys=self._fields_ordered)()
         else:
-            self._data = SemiStrictDict.create(
+            self._data = {}
-                allowed_keys=self._fields_ordered)()
 
         self._dynamic_fields = SON()
 
@@ -489,7 +489,7 @@ class BaseDocument(object):
                 else:
                     data = getattr(data, part, None)
 
-                if hasattr(data, '_changed_fields'):
+                if not isinstance(data, LazyReference) and hasattr(data, '_changed_fields'):
                     if getattr(data, '_is_document', False):
                         continue
 

mongoengine/connection.py

@@ -146,13 +146,14 @@ def get_connection(alias=DEFAULT_CONNECTION_NAME, reconnect=False):
         raise MongoEngineConnectionError(msg)
 
     def _clean_settings(settings_dict):
-        irrelevant_fields = set([
+        # set literal more efficient than calling set function
-            'name', 'username', 'password', 'authentication_source',
+        irrelevant_fields_set = {
-            'authentication_mechanism'
+            'name', 'username', 'password',
-        ])
+            'authentication_source', 'authentication_mechanism'
+        }
         return {
             k: v for k, v in settings_dict.items()
-            if k not in irrelevant_fields
+            if k not in irrelevant_fields_set
         }
 
     # Retrieve a copy of the connection settings associated with the requested

mongoengine/dereference.py

@@ -3,6 +3,7 @@ import six
 
 from mongoengine.base import (BaseDict, BaseList, EmbeddedDocumentList,
                               TopLevelDocumentMetaclass, get_document)
+from mongoengine.base.datastructures import LazyReference
 from mongoengine.connection import get_db
 from mongoengine.document import Document, EmbeddedDocument
 from mongoengine.fields import DictField, ListField, MapField, ReferenceField
@@ -99,7 +100,10 @@ class DeReference(object):
             if isinstance(item, (Document, EmbeddedDocument)):
                 for field_name, field in item._fields.iteritems():
                     v = item._data.get(field_name, None)
-                    if isinstance(v, DBRef):
+                    if isinstance(v, LazyReference):
+                        # LazyReference inherits DBRef but should not be dereferenced here !
+                        continue
+                    elif isinstance(v, DBRef):
                         reference_map.setdefault(field.document_type, set()).add(v.id)
                     elif isinstance(v, (dict, SON)) and '_ref' in v:
                         reference_map.setdefault(get_document(v['_cls']), set()).add(v['_ref'].id)
@@ -110,6 +114,9 @@ class DeReference(object):
                             if isinstance(field_cls, (Document, TopLevelDocumentMetaclass)):
                                 key = field_cls
                             reference_map.setdefault(key, set()).update(refs)
+            elif isinstance(item, LazyReference):
+                # LazyReference inherits DBRef but should not be dereferenced here !
+                continue
             elif isinstance(item, DBRef):
                 reference_map.setdefault(item.collection, set()).add(item.id)
             elif isinstance(item, (dict, SON)) and '_ref' in item:

mongoengine/document.py

@@ -320,7 +320,7 @@ class Document(BaseDocument):
         :param save_condition: only perform save if matching record in db
             satisfies condition(s) (e.g. version number).
             Raises :class:`OperationError` if the conditions are not satisfied
-        :parm signal_kwargs: (optional) kwargs dictionary to be passed to
+        :param signal_kwargs: (optional) kwargs dictionary to be passed to
             the signal calls.
 
         .. versionchanged:: 0.5

mongoengine/fields.py

@@ -26,7 +26,9 @@ except ImportError:
     Int64 = long
 
 from mongoengine.base import (BaseDocument, BaseField, ComplexBaseField,
-                              GeoJsonBaseField, ObjectIdField, get_document)
+                              GeoJsonBaseField, LazyReference, ObjectIdField,
+                              get_document)
+from mongoengine.common import _import_class
 from mongoengine.connection import DEFAULT_CONNECTION_NAME, get_db
 from mongoengine.document import Document, EmbeddedDocument
 from mongoengine.errors import DoesNotExist, InvalidQueryError, ValidationError
@@ -46,6 +48,7 @@ __all__ = (
     'GenericEmbeddedDocumentField', 'DynamicField', 'ListField',
     'SortedListField', 'EmbeddedDocumentListField', 'DictField',
     'MapField', 'ReferenceField', 'CachedReferenceField',
+    'LazyReferenceField', 'GenericLazyReferenceField',
     'GenericReferenceField', 'BinaryField', 'GridFSError', 'GridFSProxy',
     'FileField', 'ImageGridFsProxy', 'ImproperlyConfigured', 'ImageField',
     'GeoPointField', 'PointField', 'LineStringField', 'PolygonField',
@@ -483,6 +486,10 @@ class DateTimeField(BaseField):
         if not isinstance(value, six.string_types):
             return None
 
+        value = value.strip()
+        if not value:
+            return None
+
         # Attempt to parse a datetime:
         if dateutil:
             try:
@@ -682,16 +689,28 @@ class GenericEmbeddedDocumentField(BaseField):
         return value
 
     def validate(self, value, clean=True):
+        if self.choices and isinstance(value, SON):
+            for choice in self.choices:
+                if value['_cls'] == choice._class_name:
+                    return True
+
         if not isinstance(value, EmbeddedDocument):
             self.error('Invalid embedded document instance provided to an '
                        'GenericEmbeddedDocumentField')
 
         value.validate(clean=clean)
 
+    def lookup_member(self, member_name):
+        if self.choices:
+            for choice in self.choices:
+                field = choice._fields.get(member_name)
+                if field:
+                    return field
+        return None
+
     def to_mongo(self, document, use_db_field=True, fields=None):
         if document is None:
             return None
-
         data = document.to_mongo(use_db_field, fields)
         if '_cls' not in data:
             data['_cls'] = document._class_name
@@ -775,6 +794,17 @@ class ListField(ComplexBaseField):
         kwargs.setdefault('default', lambda: [])
         super(ListField, self).__init__(**kwargs)
 
+    def __get__(self, instance, owner):
+        if instance is None:
+            # Document class being used rather than a document object
+            return self
+        value = instance._data.get(self.name)
+        LazyReferenceField = _import_class('LazyReferenceField')
+        GenericLazyReferenceField = _import_class('GenericLazyReferenceField')
+        if isinstance(self.field, (LazyReferenceField, GenericLazyReferenceField)) and value:
+            instance._data[self.name] = [self.field.build_lazyref(x) for x in value]
+        return super(ListField, self).__get__(instance, owner)
+
     def validate(self, value):
         """Make sure that a list of valid fields is being used."""
         if (not isinstance(value, (list, tuple, QuerySet)) or
@@ -949,6 +979,15 @@ class ReferenceField(BaseField):
     """A reference to a document that will be automatically dereferenced on
     access (lazily).
 
+    Note this means you will get a database I/O access everytime you access
+    this field. This is necessary because the field returns a :class:`~mongoengine.Document`
+    which precise type can depend of the value of the `_cls` field present in the
+    document in database.
+    In short, using this type of field can lead to poor performances (especially
+    if you access this field only to retrieve it `pk` field which is already
+    known before dereference). To solve this you should consider using the
+    :class:`~mongoengine.fields.LazyReferenceField`.
+
     Use the `reverse_delete_rule` to handle what should happen if the document
     the field is referencing is deleted.  EmbeddedDocuments, DictFields and
     MapFields does not support reverse_delete_rule and an `InvalidDocumentError`
@@ -1083,8 +1122,8 @@ class ReferenceField(BaseField):
 
     def validate(self, value):
 
-        if not isinstance(value, (self.document_type, DBRef, ObjectId)):
+        if not isinstance(value, (self.document_type, LazyReference, DBRef, ObjectId)):
-            self.error('A ReferenceField only accepts DBRef, ObjectId or documents')
+            self.error('A ReferenceField only accepts DBRef, LazyReference, ObjectId or documents')
 
         if isinstance(value, Document) and value.id is None:
             self.error('You can only reference documents once they have been '
@@ -1259,6 +1298,12 @@ class GenericReferenceField(BaseField):
     """A reference to *any* :class:`~mongoengine.document.Document` subclass
     that will be automatically dereferenced on access (lazily).
 
+    Note this field works the same way as :class:`~mongoengine.document.ReferenceField`,
+    doing database I/O access the first time it is accessed (even if it's to access
+    it ``pk`` or ``id`` field).
+    To solve this you should consider using the
+    :class:`~mongoengine.fields.GenericLazyReferenceField`.
+
     .. note ::
         * Any documents used as a generic reference must be registered in the
           document registry.  Importing the model will automatically register
@@ -1461,6 +1506,9 @@ class GridFSProxy(object):
         else:
             return False
 
+    def __ne__(self, other):
+        return not self == other
+
     @property
     def fs(self):
         if not self._fs:
@@ -2134,3 +2182,195 @@ class MultiPolygonField(GeoJsonBaseField):
     .. versionadded:: 0.9
     """
     _type = 'MultiPolygon'
+
+
+class LazyReferenceField(BaseField):
+    """A really lazy reference to a document.
+    Unlike the :class:`~mongoengine.fields.ReferenceField` it must be manually
+    dereferenced using it ``fetch()`` method.
+
+    .. versionadded:: 0.15
+    """
+
+    def __init__(self, document_type, passthrough=False, dbref=False,
+                 reverse_delete_rule=DO_NOTHING, **kwargs):
+        """Initialises the Reference Field.
+
+        :param dbref:  Store the reference as :class:`~pymongo.dbref.DBRef`
+          or as the :class:`~pymongo.objectid.ObjectId`.id .
+        :param reverse_delete_rule: Determines what to do when the referring
+          object is deleted
+        :param passthrough: When trying to access unknown fields, the
+        :class:`~mongoengine.base.datastructure.LazyReference` instance will
+        automatically call `fetch()` and try to retrive the field on the fetched
+        document. Note this only work getting field (not setting or deleting).
+        """
+        if (
+            not isinstance(document_type, six.string_types) and
+            not issubclass(document_type, Document)
+        ):
+            self.error('Argument to LazyReferenceField constructor must be a '
+                       'document class or a string')
+
+        self.dbref = dbref
+        self.passthrough = passthrough
+        self.document_type_obj = document_type
+        self.reverse_delete_rule = reverse_delete_rule
+        super(LazyReferenceField, self).__init__(**kwargs)
+
+    @property
+    def document_type(self):
+        if isinstance(self.document_type_obj, six.string_types):
+            if self.document_type_obj == RECURSIVE_REFERENCE_CONSTANT:
+                self.document_type_obj = self.owner_document
+            else:
+                self.document_type_obj = get_document(self.document_type_obj)
+        return self.document_type_obj
+
+    def build_lazyref(self, value):
+        if isinstance(value, LazyReference):
+            if value.passthrough != self.passthrough:
+                value = LazyReference(value.document_type, value.pk, passthrough=self.passthrough)
+        elif value is not None:
+            if isinstance(value, self.document_type):
+                value = LazyReference(self.document_type, value.pk, passthrough=self.passthrough)
+            elif isinstance(value, DBRef):
+                value = LazyReference(self.document_type, value.id, passthrough=self.passthrough)
+            else:
+                # value is the primary key of the referenced document
+                value = LazyReference(self.document_type, value, passthrough=self.passthrough)
+        return value
+
+    def __get__(self, instance, owner):
+        """Descriptor to allow lazy dereferencing."""
+        if instance is None:
+            # Document class being used rather than a document object
+            return self
+
+        value = self.build_lazyref(instance._data.get(self.name))
+        if value:
+            instance._data[self.name] = value
+
+        return super(LazyReferenceField, self).__get__(instance, owner)
+
+    def to_mongo(self, value):
+        if isinstance(value, LazyReference):
+            pk = value.pk
+        elif isinstance(value, self.document_type):
+            pk = value.pk
+        elif isinstance(value, DBRef):
+            pk = value.id
+        else:
+            # value is the primary key of the referenced document
+            pk = value
+        id_field_name = self.document_type._meta['id_field']
+        id_field = self.document_type._fields[id_field_name]
+        pk = id_field.to_mongo(pk)
+        if self.dbref:
+            return DBRef(self.document_type._get_collection_name(), pk)
+        else:
+            return pk
+
+    def validate(self, value):
+        if isinstance(value, LazyReference):
+            if value.collection != self.document_type._get_collection_name():
+                self.error('Reference must be on a `%s` document.' % self.document_type)
+            pk = value.pk
+        elif isinstance(value, self.document_type):
+            pk = value.pk
+        elif isinstance(value, DBRef):
+            # TODO: check collection ?
+            collection = self.document_type._get_collection_name()
+            if value.collection != collection:
+                self.error("DBRef on bad collection (must be on `%s`)" % collection)
+            pk = value.id
+        else:
+            # value is the primary key of the referenced document
+            id_field_name = self.document_type._meta['id_field']
+            id_field = getattr(self.document_type, id_field_name)
+            pk = value
+            try:
+                id_field.validate(pk)
+            except ValidationError:
+                self.error(
+                    "value should be `{0}` document, LazyReference or DBRef on `{0}` "
+                    "or `{0}`'s primary key (i.e. `{1}`)".format(
+                        self.document_type.__name__, type(id_field).__name__))
+
+        if pk is None:
+            self.error('You can only reference documents once they have been '
+                       'saved to the database')
+
+    def prepare_query_value(self, op, value):
+        if value is None:
+            return None
+        super(LazyReferenceField, self).prepare_query_value(op, value)
+        return self.to_mongo(value)
+
+    def lookup_member(self, member_name):
+        return self.document_type._fields.get(member_name)
+
+
+class GenericLazyReferenceField(GenericReferenceField):
+    """A reference to *any* :class:`~mongoengine.document.Document` subclass
+    that will be automatically dereferenced on access (lazily).
+    Unlike the :class:`~mongoengine.fields.GenericReferenceField` it must be
+    manually dereferenced using it ``fetch()`` method.
+
+    .. note ::
+        * Any documents used as a generic reference must be registered in the
+          document registry.  Importing the model will automatically register
+          it.
+
+        * You can use the choices param to limit the acceptable Document types
+
+    .. versionadded:: 0.15
+    """
+
+    def __init__(self, *args, **kwargs):
+        self.passthrough = kwargs.pop('passthrough', False)
+        super(GenericLazyReferenceField, self).__init__(*args, **kwargs)
+
+    def _validate_choices(self, value):
+        if isinstance(value, LazyReference):
+            value = value.document_type._class_name
+        super(GenericLazyReferenceField, self)._validate_choices(value)
+
+    def build_lazyref(self, value):
+        if isinstance(value, LazyReference):
+            if value.passthrough != self.passthrough:
+                value = LazyReference(value.document_type, value.pk, passthrough=self.passthrough)
+        elif value is not None:
+            if isinstance(value, (dict, SON)):
+                value = LazyReference(get_document(value['_cls']), value['_ref'].id, passthrough=self.passthrough)
+            elif isinstance(value, Document):
+                value = LazyReference(type(value), value.pk, passthrough=self.passthrough)
+        return value
+
+    def __get__(self, instance, owner):
+        if instance is None:
+            return self
+
+        value = self.build_lazyref(instance._data.get(self.name))
+        if value:
+            instance._data[self.name] = value
+
+        return super(GenericLazyReferenceField, self).__get__(instance, owner)
+
+    def validate(self, value):
+        if isinstance(value, LazyReference) and value.pk is None:
+            self.error('You can only reference documents once they have been'
+                       ' saved to the database')
+        return super(GenericLazyReferenceField, self).validate(value)
+
+    def to_mongo(self, document):
+        if document is None:
+            return None
+
+        if isinstance(document, LazyReference):
+            return SON((
+                ('_cls', document.document_type._class_name),
+                ('_ref', DBRef(document.document_type._get_collection_name(), document.pk))
+            ))
+        else:
+            return super(GenericLazyReferenceField, self).to_mongo(document)

mongoengine/queryset/base.py

@@ -1722,25 +1722,33 @@ class BaseQuerySet(object):
         return frequencies
 
     def _fields_to_dbfields(self, fields):
-        """Translate fields paths to its db equivalents"""
+        """Translate fields' paths to their db equivalents."""
-        ret = []
         subclasses = []
-        document = self._document
+        if self._document._meta['allow_inheritance']:
-        if document._meta['allow_inheritance']:
             subclasses = [get_document(x)
-                          for x in document._subclasses][1:]
+                          for x in self._document._subclasses][1:]
+
+        db_field_paths = []
         for field in fields:
+            field_parts = field.split('.')
             try:
-                field = '.'.join(f.db_field for f in
+                field = '.'.join(
-                                 document._lookup_field(field.split('.')))
+                    f if isinstance(f, six.string_types) else f.db_field
-                ret.append(field)
+                    for f in self._document._lookup_field(field_parts)
+                )
+                db_field_paths.append(field)
             except LookUpError as err:
                 found = False
+
+                # If a field path wasn't found on the main document, go
+                # through its subclasses and see if it exists on any of them.
                 for subdoc in subclasses:
                     try:
-                        subfield = '.'.join(f.db_field for f in
+                        subfield = '.'.join(
-                                            subdoc._lookup_field(field.split('.')))
+                            f if isinstance(f, six.string_types) else f.db_field
-                        ret.append(subfield)
+                            for f in subdoc._lookup_field(field_parts)
+                        )
+                        db_field_paths.append(subfield)
                         found = True
                         break
                     except LookUpError:
@@ -1748,7 +1756,8 @@ class BaseQuerySet(object):
 
                 if not found:
                     raise err
-        return ret
+
+        return db_field_paths
 
     def _get_order_by(self, keys):
         """Given a list of MongoEngine-style sort keys, return a list

mongoengine/queryset/queryset.py

@@ -1,3 +1,5 @@
+import six
+
 from mongoengine.errors import OperationError
 from mongoengine.queryset.base import (BaseQuerySet, CASCADE, DENY, DO_NOTHING,
                                        NULLIFY, PULL)
@@ -112,7 +114,7 @@ class QuerySet(BaseQuerySet):
         # Pull in ITER_CHUNK_SIZE docs from the database and store them in
         # the result cache.
         try:
-            for _ in xrange(ITER_CHUNK_SIZE):
+            for _ in six.moves.range(ITER_CHUNK_SIZE):
                 self._result_cache.append(self.next())
         except StopIteration:
             # Getting this exception means there are no more docs in the
@@ -166,7 +168,7 @@ class QuerySetNoCache(BaseQuerySet):
             return '.. queryset mid-iteration ..'
 
         data = []
-        for _ in xrange(REPR_OUTPUT_SIZE + 1):
+        for _ in six.moves.range(REPR_OUTPUT_SIZE + 1):
             try:
                 data.append(self.next())
             except StopIteration:

mongoengine/queryset/transform.py

@@ -284,7 +284,9 @@ def update(_doc_cls=None, **update):
             if isinstance(field, GeoJsonBaseField):
                 value = field.to_mongo(value)
 
-            if op in (None, 'set', 'push', 'pull'):
+            if op == 'push' and isinstance(value, (list, tuple, set)):
+                value = [field.prepare_query_value(op, v) for v in value]
+            elif op in (None, 'set', 'push', 'pull'):
                 if field.required or value is not None:
                     value = field.prepare_query_value(op, value)
             elif op in ('pushAll', 'pullAll'):
@@ -333,10 +335,20 @@ def update(_doc_cls=None, **update):
                 value = {key: value}
         elif op == 'addToSet' and isinstance(value, list):
             value = {key: {'$each': value}}
+        elif op == 'push':
+            if parts[-1].isdigit():
+                key = parts[0]
+                position = int(parts[-1])
+                # $position expects an iterable. If pushing a single value,
+                # wrap it in a list.
+                if not isinstance(value, (set, tuple, list)):
+                    value = [value]
+                value = {key: {'$each': value, '$position': position}}
+            else:
+                value = {key: value}
         else:
             value = {key: value}
         key = '$' + op
-
         if key not in mongo_update:
             mongo_update[key] = value
         elif key in mongo_update and isinstance(mongo_update[key], dict):

setup.cfg

@@ -1,11 +1,11 @@
 [nosetests]
 verbosity=2
 detailed-errors=1
-tests=tests
+#tests=tests
 cover-package=mongoengine
 
 [flake8]
-ignore=E501,F401,F403,F405,I201
+ignore=E501,F401,F403,F405,I201,I202
 exclude=build,dist,docs,venv,venv3,.tox,.eggs,tests
 max-complexity=47
 application-import-names=mongoengine,tests

setup.py

@@ -70,9 +70,9 @@ setup(
     name='mongoengine',
     version=VERSION,
     author='Harry Marr',
-    author_email='harry.marr@{nospam}gmail.com',
+    author_email='harry.marr@gmail.com',
-    maintainer="Ross Lawley",
+    maintainer="Stefan Wojcik",
-    maintainer_email="ross.lawley@{nospam}gmail.com",
+    maintainer_email="wojcikstefan@gmail.com",
     url='http://mongoengine.org/',
     download_url='https://github.com/MongoEngine/mongoengine/tarball/master',
     license='MIT',

tests/document/instance.py

@@ -22,6 +22,8 @@ from mongoengine.queryset import NULLIFY, Q
 from mongoengine.context_managers import switch_db, query_counter
 from mongoengine import signals
 
+from tests.utils import needs_mongodb_v26
+
 TEST_IMAGE_PATH = os.path.join(os.path.dirname(__file__),
                                '../fields/mongoengine.png')
 
@@ -826,6 +828,22 @@ class InstanceTest(unittest.TestCase):
 
         self.assertDbEqual([dict(other_doc.to_mongo()), dict(doc.to_mongo())])
 
+    @needs_mongodb_v26
+    def test_modify_with_positional_push(self):
+        class BlogPost(Document):
+            tags = ListField(StringField())
+
+        post = BlogPost.objects.create(tags=['python'])
+        self.assertEqual(post.tags, ['python'])
+        post.modify(push__tags__0=['code', 'mongo'])
+        self.assertEqual(post.tags, ['code', 'mongo', 'python'])
+
+        # Assert same order of the list items is maintained in the db
+        self.assertEqual(
+            BlogPost._get_collection().find_one({'_id': post.pk})['tags'],
+            ['code', 'mongo', 'python']
+        )
+
     def test_save(self):
         """Ensure that a document may be saved in the database."""
 
@@ -3149,6 +3167,33 @@ class InstanceTest(unittest.TestCase):
 
         person.update(set__height=2.0)
 
+    @needs_mongodb_v26
+    def test_push_with_position(self):
+        """Ensure that push with position works properly for an instance."""
+        class BlogPost(Document):
+            slug = StringField()
+            tags = ListField(StringField())
+
+        blog = BlogPost()
+        blog.slug = "ABC"
+        blog.tags = ["python"]
+        blog.save()
+
+        blog.update(push__tags__0=["mongodb", "code"])
+        blog.reload()
+        self.assertEqual(blog.tags, ['mongodb', 'code', 'python'])
+
+    def test_push_nested_list(self):
+        """Ensure that push update works in nested list"""
+        class BlogPost(Document):
+            slug = StringField()
+            tags = ListField()
+
+        blog = BlogPost(slug="test").save()
+        blog.update(push__tags=["value1", 123])
+        blog.reload()
+        self.assertEqual(blog.tags, [["value1", 123]])
+
 
 if __name__ == '__main__':
     unittest.main()

tests/fields/fields.py

@@ -26,7 +26,7 @@ except ImportError:
 from mongoengine import *
 from mongoengine.connection import get_db
 from mongoengine.base import (BaseDict, BaseField, EmbeddedDocumentList,
-                              _document_registry)
+                              _document_registry, LazyReference)
 
 from tests.utils import MongoDBTestCase
 
@@ -35,6 +35,28 @@ __all__ = ("FieldTest", "EmbeddedDocumentListFieldTestCase")
 
 class FieldTest(MongoDBTestCase):
 
+    def test_datetime_from_empty_string(self):
+        """
+        Ensure an exception is raised when trying to
+        cast an empty string to datetime.
+        """
+        class MyDoc(Document):
+            dt = DateTimeField()
+
+        md = MyDoc(dt='')
+        self.assertRaises(ValidationError, md.save)
+
+    def test_datetime_from_whitespace_string(self):
+        """
+        Ensure an exception is raised when trying to
+        cast a whitespace-only string to datetime.
+        """
+        class MyDoc(Document):
+            dt = DateTimeField()
+
+        md = MyDoc(dt='   ')
+        self.assertRaises(ValidationError, md.save)
+
     def test_default_values_nothing_set(self):
         """Ensure that default field values are used when creating
         a document.
@@ -909,7 +931,9 @@ class FieldTest(MongoDBTestCase):
             comments = ListField(EmbeddedDocumentField(Comment))
             tags = ListField(StringField())
             authors = ListField(ReferenceField(User))
+            authors_as_lazy = ListField(LazyReferenceField(User))
             generic = ListField(GenericReferenceField())
+            generic_as_lazy = ListField(GenericLazyReferenceField())
 
         User.drop_collection()
         BlogPost.drop_collection()
@@ -947,6 +971,15 @@ class FieldTest(MongoDBTestCase):
         post.authors = [user]
         post.validate()
 
+        post.authors_as_lazy = [Comment()]
+        self.assertRaises(ValidationError, post.validate)
+
+        post.authors_as_lazy = [User()]
+        self.assertRaises(ValidationError, post.validate)
+
+        post.authors_as_lazy = [user]
+        post.validate()
+
         post.generic = [1, 2]
         self.assertRaises(ValidationError, post.validate)
 
@@ -959,6 +992,18 @@ class FieldTest(MongoDBTestCase):
         post.generic = [user]
         post.validate()
 
+        post.generic_as_lazy = [1, 2]
+        self.assertRaises(ValidationError, post.validate)
+
+        post.generic_as_lazy = [User(), Comment()]
+        self.assertRaises(ValidationError, post.validate)
+
+        post.generic_as_lazy = [Comment()]
+        self.assertRaises(ValidationError, post.validate)
+
+        post.generic_as_lazy = [user]
+        post.validate()
+
     def test_sorted_list_sorting(self):
         """Ensure that a sorted list field properly sorts values.
         """
@@ -4576,5 +4621,522 @@ class CachedReferenceFieldTest(MongoDBTestCase):
         self.assertTrue(isinstance(ocorrence.animal, Animal))
 
 
+class LazyReferenceFieldTest(MongoDBTestCase):
+    def test_lazy_reference_config(self):
+        # Make sure ReferenceField only accepts a document class or a string
+        # with a document class name.
+        self.assertRaises(ValidationError, LazyReferenceField, EmbeddedDocument)
+
+    def test_lazy_reference_simple(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            person = StringField()
+            animal = LazyReferenceField(Animal)
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        animal = Animal(name="Leopard", tag="heavy").save()
+        Ocurrence(person="test", animal=animal).save()
+        p = Ocurrence.objects.get()
+        self.assertIsInstance(p.animal, LazyReference)
+        fetched_animal = p.animal.fetch()
+        self.assertEqual(fetched_animal, animal)
+        # `fetch` keep cache on referenced document by default...
+        animal.tag = "not so heavy"
+        animal.save()
+        double_fetch = p.animal.fetch()
+        self.assertIs(fetched_animal, double_fetch)
+        self.assertEqual(double_fetch.tag, "heavy")
+        # ...unless specified otherwise
+        fetch_force = p.animal.fetch(force=True)
+        self.assertIsNot(fetch_force, fetched_animal)
+        self.assertEqual(fetch_force.tag, "not so heavy")
+
+    def test_lazy_reference_fetch_invalid_ref(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            person = StringField()
+            animal = LazyReferenceField(Animal)
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        animal = Animal(name="Leopard", tag="heavy").save()
+        Ocurrence(person="test", animal=animal).save()
+        animal.delete()
+        p = Ocurrence.objects.get()
+        self.assertIsInstance(p.animal, LazyReference)
+        with self.assertRaises(DoesNotExist):
+            p.animal.fetch()
+
+    def test_lazy_reference_set(self):
+        class Animal(Document):
+            meta = {'allow_inheritance': True}
+
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            person = StringField()
+            animal = LazyReferenceField(Animal)
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        class SubAnimal(Animal):
+            nick = StringField()
+
+        animal = Animal(name="Leopard", tag="heavy").save()
+        sub_animal = SubAnimal(nick='doggo', name='dog').save()
+        for ref in (
+                animal,
+                animal.pk,
+                DBRef(animal._get_collection_name(), animal.pk),
+                LazyReference(Animal, animal.pk),
+
+                sub_animal,
+                sub_animal.pk,
+                DBRef(sub_animal._get_collection_name(), sub_animal.pk),
+                LazyReference(SubAnimal, sub_animal.pk),
+                ):
+            p = Ocurrence(person="test", animal=ref).save()
+            p.reload()
+            self.assertIsInstance(p.animal, LazyReference)
+            p.animal.fetch()
+
+    def test_lazy_reference_bad_set(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            person = StringField()
+            animal = LazyReferenceField(Animal)
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        class BadDoc(Document):
+            pass
+
+        animal = Animal(name="Leopard", tag="heavy").save()
+        baddoc = BadDoc().save()
+        for bad in (
+                42,
+                'foo',
+                baddoc,
+                DBRef(baddoc._get_collection_name(), animal.pk),
+                LazyReference(BadDoc, animal.pk)
+                ):
+            with self.assertRaises(ValidationError):
+                p = Ocurrence(person="test", animal=bad).save()
+
+    def test_lazy_reference_query_conversion(self):
+        """Ensure that LazyReferenceFields can be queried using objects and values
+        of the type of the primary key of the referenced object.
+        """
+        class Member(Document):
+            user_num = IntField(primary_key=True)
+
+        class BlogPost(Document):
+            title = StringField()
+            author = LazyReferenceField(Member, dbref=False)
+
+        Member.drop_collection()
+        BlogPost.drop_collection()
+
+        m1 = Member(user_num=1)
+        m1.save()
+        m2 = Member(user_num=2)
+        m2.save()
+
+        post1 = BlogPost(title='post 1', author=m1)
+        post1.save()
+
+        post2 = BlogPost(title='post 2', author=m2)
+        post2.save()
+
+        post = BlogPost.objects(author=m1).first()
+        self.assertEqual(post.id, post1.id)
+
+        post = BlogPost.objects(author=m2).first()
+        self.assertEqual(post.id, post2.id)
+
+        # Same thing by passing a LazyReference instance
+        post = BlogPost.objects(author=LazyReference(Member, m2.pk)).first()
+        self.assertEqual(post.id, post2.id)
+
+    def test_lazy_reference_query_conversion_dbref(self):
+        """Ensure that LazyReferenceFields can be queried using objects and values
+        of the type of the primary key of the referenced object.
+        """
+        class Member(Document):
+            user_num = IntField(primary_key=True)
+
+        class BlogPost(Document):
+            title = StringField()
+            author = LazyReferenceField(Member, dbref=True)
+
+        Member.drop_collection()
+        BlogPost.drop_collection()
+
+        m1 = Member(user_num=1)
+        m1.save()
+        m2 = Member(user_num=2)
+        m2.save()
+
+        post1 = BlogPost(title='post 1', author=m1)
+        post1.save()
+
+        post2 = BlogPost(title='post 2', author=m2)
+        post2.save()
+
+        post = BlogPost.objects(author=m1).first()
+        self.assertEqual(post.id, post1.id)
+
+        post = BlogPost.objects(author=m2).first()
+        self.assertEqual(post.id, post2.id)
+
+        # Same thing by passing a LazyReference instance
+        post = BlogPost.objects(author=LazyReference(Member, m2.pk)).first()
+        self.assertEqual(post.id, post2.id)
+
+    def test_lazy_reference_passthrough(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            animal = LazyReferenceField(Animal, passthrough=False)
+            animal_passthrough = LazyReferenceField(Animal, passthrough=True)
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        animal = Animal(name="Leopard", tag="heavy").save()
+        Ocurrence(animal=animal, animal_passthrough=animal).save()
+        p = Ocurrence.objects.get()
+        self.assertIsInstance(p.animal, LazyReference)
+        with self.assertRaises(KeyError):
+            p.animal['name']
+        with self.assertRaises(AttributeError):
+            p.animal.name
+        self.assertEqual(p.animal.pk, animal.pk)
+
+        self.assertEqual(p.animal_passthrough.name, "Leopard")
+        self.assertEqual(p.animal_passthrough['name'], "Leopard")
+
+        # Should not be able to access referenced document's methods
+        with self.assertRaises(AttributeError):
+            p.animal.save
+        with self.assertRaises(KeyError):
+            p.animal['save']
+
+    def test_lazy_reference_not_set(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            person = StringField()
+            animal = LazyReferenceField(Animal)
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        Ocurrence(person='foo').save()
+        p = Ocurrence.objects.get()
+        self.assertIs(p.animal, None)
+
+    def test_lazy_reference_equality(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        Animal.drop_collection()
+
+        animal = Animal(name="Leopard", tag="heavy").save()
+        animalref = LazyReference(Animal, animal.pk)
+        self.assertEqual(animal, animalref)
+        self.assertEqual(animalref, animal)
+
+        other_animalref = LazyReference(Animal, ObjectId("54495ad94c934721ede76f90"))
+        self.assertNotEqual(animal, other_animalref)
+        self.assertNotEqual(other_animalref, animal)
+
+    def test_lazy_reference_embedded(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class EmbeddedOcurrence(EmbeddedDocument):
+            in_list = ListField(LazyReferenceField(Animal))
+            direct = LazyReferenceField(Animal)
+
+        class Ocurrence(Document):
+            in_list = ListField(LazyReferenceField(Animal))
+            in_embedded = EmbeddedDocumentField(EmbeddedOcurrence)
+            direct = LazyReferenceField(Animal)
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        animal1 = Animal('doggo').save()
+        animal2 = Animal('cheeta').save()
+
+        def check_fields_type(occ):
+            self.assertIsInstance(occ.direct, LazyReference)
+            for elem in occ.in_list:
+                self.assertIsInstance(elem, LazyReference)
+            self.assertIsInstance(occ.in_embedded.direct, LazyReference)
+            for elem in occ.in_embedded.in_list:
+                self.assertIsInstance(elem, LazyReference)
+
+        occ = Ocurrence(
+            in_list=[animal1, animal2],
+            in_embedded={'in_list': [animal1, animal2], 'direct': animal1},
+            direct=animal1
+        ).save()
+        check_fields_type(occ)
+        occ.reload()
+        check_fields_type(occ)
+        occ.direct = animal1.id
+        occ.in_list = [animal1.id, animal2.id]
+        occ.in_embedded.direct = animal1.id
+        occ.in_embedded.in_list = [animal1.id, animal2.id]
+        check_fields_type(occ)
+
+
+class GenericLazyReferenceFieldTest(MongoDBTestCase):
+    def test_generic_lazy_reference_simple(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            person = StringField()
+            animal = GenericLazyReferenceField()
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        animal = Animal(name="Leopard", tag="heavy").save()
+        Ocurrence(person="test", animal=animal).save()
+        p = Ocurrence.objects.get()
+        self.assertIsInstance(p.animal, LazyReference)
+        fetched_animal = p.animal.fetch()
+        self.assertEqual(fetched_animal, animal)
+        # `fetch` keep cache on referenced document by default...
+        animal.tag = "not so heavy"
+        animal.save()
+        double_fetch = p.animal.fetch()
+        self.assertIs(fetched_animal, double_fetch)
+        self.assertEqual(double_fetch.tag, "heavy")
+        # ...unless specified otherwise
+        fetch_force = p.animal.fetch(force=True)
+        self.assertIsNot(fetch_force, fetched_animal)
+        self.assertEqual(fetch_force.tag, "not so heavy")
+
+    def test_generic_lazy_reference_choices(self):
+        class Animal(Document):
+            name = StringField()
+
+        class Vegetal(Document):
+            name = StringField()
+
+        class Mineral(Document):
+            name = StringField()
+
+        class Ocurrence(Document):
+            living_thing = GenericLazyReferenceField(choices=[Animal, Vegetal])
+            thing = GenericLazyReferenceField()
+
+        Animal.drop_collection()
+        Vegetal.drop_collection()
+        Mineral.drop_collection()
+        Ocurrence.drop_collection()
+
+        animal = Animal(name="Leopard").save()
+        vegetal = Vegetal(name="Oak").save()
+        mineral = Mineral(name="Granite").save()
+
+        occ_animal = Ocurrence(living_thing=animal, thing=animal).save()
+        occ_vegetal = Ocurrence(living_thing=vegetal, thing=vegetal).save()
+        with self.assertRaises(ValidationError):
+            Ocurrence(living_thing=mineral).save()
+
+        occ = Ocurrence.objects.get(living_thing=animal)
+        self.assertEqual(occ, occ_animal)
+        self.assertIsInstance(occ.thing, LazyReference)
+        self.assertIsInstance(occ.living_thing, LazyReference)
+
+        occ.thing = vegetal
+        occ.living_thing = vegetal
+        occ.save()
+
+        occ.thing = mineral
+        occ.living_thing = mineral
+        with self.assertRaises(ValidationError):
+            occ.save()
+
+    def test_generic_lazy_reference_set(self):
+        class Animal(Document):
+            meta = {'allow_inheritance': True}
+
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            person = StringField()
+            animal = GenericLazyReferenceField()
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        class SubAnimal(Animal):
+            nick = StringField()
+
+        animal = Animal(name="Leopard", tag="heavy").save()
+        sub_animal = SubAnimal(nick='doggo', name='dog').save()
+        for ref in (
+                animal,
+                LazyReference(Animal, animal.pk),
+                {'_cls': 'Animal', '_ref': DBRef(animal._get_collection_name(), animal.pk)},
+
+                sub_animal,
+                LazyReference(SubAnimal, sub_animal.pk),
+                {'_cls': 'SubAnimal', '_ref': DBRef(sub_animal._get_collection_name(), sub_animal.pk)},
+                ):
+            p = Ocurrence(person="test", animal=ref).save()
+            p.reload()
+            self.assertIsInstance(p.animal, (LazyReference, Document))
+            p.animal.fetch()
+
+    def test_generic_lazy_reference_bad_set(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            person = StringField()
+            animal = GenericLazyReferenceField(choices=['Animal'])
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        class BadDoc(Document):
+            pass
+
+        animal = Animal(name="Leopard", tag="heavy").save()
+        baddoc = BadDoc().save()
+        for bad in (
+                42,
+                'foo',
+                baddoc,
+                LazyReference(BadDoc, animal.pk)
+                ):
+            with self.assertRaises(ValidationError):
+                p = Ocurrence(person="test", animal=bad).save()
+
+    def test_generic_lazy_reference_query_conversion(self):
+        class Member(Document):
+            user_num = IntField(primary_key=True)
+
+        class BlogPost(Document):
+            title = StringField()
+            author = GenericLazyReferenceField()
+
+        Member.drop_collection()
+        BlogPost.drop_collection()
+
+        m1 = Member(user_num=1)
+        m1.save()
+        m2 = Member(user_num=2)
+        m2.save()
+
+        post1 = BlogPost(title='post 1', author=m1)
+        post1.save()
+
+        post2 = BlogPost(title='post 2', author=m2)
+        post2.save()
+
+        post = BlogPost.objects(author=m1).first()
+        self.assertEqual(post.id, post1.id)
+
+        post = BlogPost.objects(author=m2).first()
+        self.assertEqual(post.id, post2.id)
+
+        # Same thing by passing a LazyReference instance
+        post = BlogPost.objects(author=LazyReference(Member, m2.pk)).first()
+        self.assertEqual(post.id, post2.id)
+
+    def test_generic_lazy_reference_not_set(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class Ocurrence(Document):
+            person = StringField()
+            animal = GenericLazyReferenceField()
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        Ocurrence(person='foo').save()
+        p = Ocurrence.objects.get()
+        self.assertIs(p.animal, None)
+
+    def test_generic_lazy_reference_embedded(self):
+        class Animal(Document):
+            name = StringField()
+            tag = StringField()
+
+        class EmbeddedOcurrence(EmbeddedDocument):
+            in_list = ListField(GenericLazyReferenceField())
+            direct = GenericLazyReferenceField()
+
+        class Ocurrence(Document):
+            in_list = ListField(GenericLazyReferenceField())
+            in_embedded = EmbeddedDocumentField(EmbeddedOcurrence)
+            direct = GenericLazyReferenceField()
+
+        Animal.drop_collection()
+        Ocurrence.drop_collection()
+
+        animal1 = Animal('doggo').save()
+        animal2 = Animal('cheeta').save()
+
+        def check_fields_type(occ):
+            self.assertIsInstance(occ.direct, LazyReference)
+            for elem in occ.in_list:
+                self.assertIsInstance(elem, LazyReference)
+            self.assertIsInstance(occ.in_embedded.direct, LazyReference)
+            for elem in occ.in_embedded.in_list:
+                self.assertIsInstance(elem, LazyReference)
+
+        occ = Ocurrence(
+            in_list=[animal1, animal2],
+            in_embedded={'in_list': [animal1, animal2], 'direct': animal1},
+            direct=animal1
+        ).save()
+        check_fields_type(occ)
+        occ.reload()
+        check_fields_type(occ)
+        animal1_ref = {'_cls': 'Animal', '_ref': DBRef(animal1._get_collection_name(), animal1.pk)}
+        animal2_ref = {'_cls': 'Animal', '_ref': DBRef(animal2._get_collection_name(), animal2.pk)}
+        occ.direct = animal1_ref
+        occ.in_list = [animal1_ref, animal2_ref]
+        occ.in_embedded.direct = animal1_ref
+        occ.in_embedded.in_list = [animal1_ref, animal2_ref]
+        check_fields_type(occ)
+
+
 if __name__ == '__main__':
     unittest.main()

tests/queryset/field_list.py

@@ -197,14 +197,18 @@ class OnlyExcludeAllTest(unittest.TestCase):
             title = StringField()
             text = StringField()
 
+        class VariousData(EmbeddedDocument):
+            some = BooleanField()
+
         class BlogPost(Document):
             content = StringField()
             author = EmbeddedDocumentField(User)
             comments = ListField(EmbeddedDocumentField(Comment))
+            various = MapField(field=EmbeddedDocumentField(VariousData))
 
         BlogPost.drop_collection()
 
-        post = BlogPost(content='Had a good coffee today...')
+        post = BlogPost(content='Had a good coffee today...', various={'test_dynamic':{'some': True}})
         post.author = User(name='Test User')
         post.comments = [Comment(title='I aggree', text='Great post!'), Comment(title='Coffee', text='I hate coffee')]
         post.save()
@@ -215,6 +219,9 @@ class OnlyExcludeAllTest(unittest.TestCase):
         self.assertEqual(obj.author.name, 'Test User')
         self.assertEqual(obj.comments, [])
 
+        obj = BlogPost.objects.only('various.test_dynamic.some').get()
+        self.assertEqual(obj.various["test_dynamic"].some, True)
+
         obj = BlogPost.objects.only('content', 'comments.title',).get()
         self.assertEqual(obj.content, 'Had a good coffee today...')
         self.assertEqual(obj.author, None)

tests/queryset/geo.py

@@ -510,6 +510,24 @@ class GeoQueriesTest(MongoDBTestCase):
         roads = Road.objects.filter(poly__geo_intersects={"$geometry": polygon}).count()
         self.assertEqual(1, roads)
 
+    def test_aspymongo_with_only(self):
+        """Ensure as_pymongo works with only"""
+        class Place(Document):
+            location = PointField()
+
+        Place.drop_collection()
+        p = Place(location=[24.946861267089844, 60.16311983618494])
+        p.save()
+        qs = Place.objects().only('location')
+        self.assertDictEqual(
+            qs.as_pymongo()[0]['location'],
+            {u'type': u'Point',
+             u'coordinates': [
+                24.946861267089844,
+                60.16311983618494]
+            }
+        )
+
     def test_2dsphere_point_sets_correctly(self):
         class Location(Document):
             loc = PointField()

tests/queryset/modify.py

@@ -1,6 +1,8 @@
 import unittest
 
-from mongoengine import connect, Document, IntField
+from mongoengine import connect, Document, IntField, StringField, ListField
+
+from tests.utils import needs_mongodb_v26
 
 __all__ = ("FindAndModifyTest",)
 
@@ -94,6 +96,37 @@ class FindAndModifyTest(unittest.TestCase):
         self.assertEqual(old_doc.to_mongo(), {"_id": 1})
         self.assertDbEqual([{"_id": 0, "value": 0}, {"_id": 1, "value": -1}])
 
+    @needs_mongodb_v26
+    def test_modify_with_push(self):
+        class BlogPost(Document):
+            tags = ListField(StringField())
+
+        BlogPost.drop_collection()
+
+        blog = BlogPost.objects.create()
+
+        # Push a new tag via modify with new=False (default).
+        BlogPost(id=blog.id).modify(push__tags='code')
+        self.assertEqual(blog.tags, [])
+        blog.reload()
+        self.assertEqual(blog.tags, ['code'])
+
+        # Push a new tag via modify with new=True.
+        blog = BlogPost.objects(id=blog.id).modify(push__tags='java', new=True)
+        self.assertEqual(blog.tags, ['code', 'java'])
+
+        # Push a new tag with a positional argument.
+        blog = BlogPost.objects(id=blog.id).modify(
+            push__tags__0='python',
+            new=True)
+        self.assertEqual(blog.tags, ['python', 'code', 'java'])
+
+        # Push multiple new tags with a positional argument.
+        blog = BlogPost.objects(id=blog.id).modify(
+            push__tags__1=['go', 'rust'],
+            new=True)
+        self.assertEqual(blog.tags, ['python', 'go', 'rust', 'code', 'java'])
+
 
 if __name__ == '__main__':
     unittest.main()

tests/queryset/queryset.py

@@ -1903,6 +1903,47 @@ class QuerySetTest(unittest.TestCase):
 
         BlogPost.drop_collection()
 
+    @needs_mongodb_v26
+    def test_update_push_with_position(self):
+        """Ensure that the 'push' update with position works properly.
+        """
+        class BlogPost(Document):
+            slug = StringField()
+            tags = ListField(StringField())
+
+        BlogPost.drop_collection()
+
+        post = BlogPost.objects.create(slug="test")
+
+        BlogPost.objects.filter(id=post.id).update(push__tags="code")
+        BlogPost.objects.filter(id=post.id).update(push__tags__0=["mongodb", "python"])
+        post.reload()
+        self.assertEqual(post.tags, ['mongodb', 'python', 'code'])
+
+        BlogPost.objects.filter(id=post.id).update(set__tags__2="java")
+        post.reload()
+        self.assertEqual(post.tags, ['mongodb', 'python', 'java'])
+
+        #test push with singular value
+        BlogPost.objects.filter(id=post.id).update(push__tags__0='scala')
+        post.reload()
+        self.assertEqual(post.tags, ['scala', 'mongodb', 'python', 'java'])
+
+    def test_update_push_list_of_list(self):
+        """Ensure that the 'push' update operation works in the list of list
+        """
+        class BlogPost(Document):
+            slug = StringField()
+            tags = ListField()
+
+        BlogPost.drop_collection()
+
+        post = BlogPost(slug="test").save()
+
+        BlogPost.objects.filter(slug="test").update(push__tags=["value1", 123])
+        post.reload()
+        self.assertEqual(post.tags, [["value1", 123]])
+
     def test_update_push_and_pull_add_to_set(self):
         """Ensure that the 'pull' update operation works correctly.
         """
@@ -2045,6 +2086,23 @@ class QuerySetTest(unittest.TestCase):
             Site.objects(id=s.id).update_one(
                 pull_all__collaborators__helpful__user=['Ross'])
 
+    def test_pull_in_genericembedded_field(self):
+
+        class Foo(EmbeddedDocument):
+            name = StringField()
+
+        class Bar(Document):
+            foos = ListField(GenericEmbeddedDocumentField(
+                choices=[Foo, ]))
+
+        Bar.drop_collection()
+
+        foo = Foo(name="bar")
+        bar = Bar(foos=[foo]).save()
+        Bar.objects(id=bar.id).update(pull__foos=foo)
+        bar.reload()
+        self.assertEqual(len(bar.foos), 0)
+
     def test_update_one_pop_generic_reference(self):
 
         class BlogTag(Document):
@@ -2138,6 +2196,24 @@ class QuerySetTest(unittest.TestCase):
         self.assertEqual(message.authors[1].name, "Ross")
         self.assertEqual(message.authors[2].name, "Adam")
 
+    def test_set_generic_embedded_documents(self):
+
+        class Bar(EmbeddedDocument):
+            name = StringField()
+
+        class User(Document):
+            username = StringField()
+            bar = GenericEmbeddedDocumentField(choices=[Bar,])
+
+        User.drop_collection()
+
+        User(username='abc').save()
+        User.objects(username='abc').update(
+            set__bar=Bar(name='test'), upsert=True)
+
+        user = User.objects(username='abc').first()
+        self.assertEqual(user.bar.name, "test")
+
     def test_reload_embedded_docs_instance(self):
 
         class SubDoc(EmbeddedDocument):
@@ -4764,6 +4840,30 @@ class QuerySetTest(unittest.TestCase):
         for obj in C.objects.no_sub_classes():
             self.assertEqual(obj.__class__, C)
 
+    def test_query_generic_embedded_document(self):
+        """Ensure that querying sub field on generic_embedded_field works
+        """
+        class A(EmbeddedDocument):
+            a_name = StringField()
+
+        class B(EmbeddedDocument):
+            b_name = StringField()
+
+        class Doc(Document):
+            document = GenericEmbeddedDocumentField(choices=(A, B))
+
+        Doc.drop_collection()
+        Doc(document=A(a_name='A doc')).save()
+        Doc(document=B(b_name='B doc')).save()
+
+        # Using raw in filter working fine
+        self.assertEqual(Doc.objects(
+            __raw__={'document.a_name': 'A doc'}).count(), 1)
+        self.assertEqual(Doc.objects(
+            __raw__={'document.b_name': 'B doc'}).count(), 1)
+        self.assertEqual(Doc.objects(document__a_name='A doc').count(), 1)
+        self.assertEqual(Doc.objects(document__b_name='B doc').count(), 1)
+
     def test_query_reference_to_custom_pk_doc(self):
 
         class A(Document):
@@ -4931,6 +5031,7 @@ class QuerySetTest(unittest.TestCase):
             self.assertTrue(Person.objects._has_data(),
                             'Cursor has data and returned False')
 
+    @needs_mongodb_v26
     def test_queryset_aggregation_framework(self):
         class Person(Document):
             name = StringField()
@@ -4938,13 +5039,19 @@ class QuerySetTest(unittest.TestCase):
 
         Person.drop_collection()
 
-        p1 = Person.objects.create(name="Isabella Luanna", age=16)
+        p1 = Person(name="Isabella Luanna", age=16)
-        p2 = Person.objects.create(name="Wilson Junior", age=21)
+        p1.save()
-        p3 = Person.objects.create(name="Sandra Mara", age=37)
+
+        p2 = Person(name="Wilson Junior", age=21)
+        p2.save()
+
+        p3 = Person(name="Sandra Mara", age=37)
+        p3.save()
 
         data = Person.objects(age__lte=22).aggregate(
             {'$project': {'name': {'$toUpper': '$name'}}}
         )
+
         self.assertEqual(list(data), [
             {'_id': p1.pk, 'name': "ISABELLA LUANNA"},
             {'_id': p2.pk, 'name': "WILSON JUNIOR"}
@@ -4953,6 +5060,7 @@ class QuerySetTest(unittest.TestCase):
         data = Person.objects(age__lte=22).order_by('-name').aggregate(
             {'$project': {'name': {'$toUpper': '$name'}}}
         )
+
         self.assertEqual(list(data), [
             {'_id': p2.pk, 'name': "WILSON JUNIOR"},
             {'_id': p1.pk, 'name': "ISABELLA LUANNA"}

tests/test_datastructures.py

@@ -1,6 +1,6 @@
 import unittest
 
-from mongoengine.base.datastructures import StrictDict, SemiStrictDict
+from mongoengine.base.datastructures import StrictDict
 
 
 class TestStrictDict(unittest.TestCase):
@@ -76,44 +76,5 @@ class TestStrictDict(unittest.TestCase):
         assert dict(**d) == {'a': 1, 'b': 2}
 
 
-class TestSemiSrictDict(TestStrictDict):
-    def strict_dict_class(self, *args, **kwargs):
-        return SemiStrictDict.create(*args, **kwargs)
-
-    def test_init_fails_on_nonexisting_attrs(self):
-        # disable irrelevant test
-        pass
-
-    def test_setattr_raises_on_nonexisting_attr(self):
-        # disable irrelevant test
-        pass
-
-    def test_setattr_getattr_nonexisting_attr_succeeds(self):
-        d = self.dtype()
-        d.x = 1
-        self.assertEqual(d.x, 1)
-
-    def test_init_succeeds_with_nonexisting_attrs(self):
-        d = self.dtype(a=1, b=1, c=1, x=2)
-        self.assertEqual((d.a, d.b, d.c, d.x), (1, 1, 1, 2))
-
-    def test_iter_with_nonexisting_attrs(self):
-        d = self.dtype(a=1, b=1, c=1, x=2)
-        self.assertEqual(list(d), ['a', 'b', 'c', 'x'])
-
-    def test_iteritems_with_nonexisting_attrs(self):
-        d = self.dtype(a=1, b=1, c=1, x=2)
-        self.assertEqual(list(d.iteritems()), [('a', 1), ('b', 1), ('c', 1), ('x', 2)])
-
-    def tets_cmp_with_strict_dicts(self):
-        d = self.dtype(a=1, b=1, c=1)
-        dd = StrictDict.create(("a", "b", "c"))(a=1, b=1, c=1)
-        self.assertEqual(d, dd)
-
-    def test_cmp_with_strict_dict_with_nonexisting_attrs(self):
-        d = self.dtype(a=1, b=1, c=1, x=2)
-        dd = StrictDict.create(("a", "b", "c", "x"))(a=1, b=1, c=1, x=2)
-        self.assertEqual(d, dd)
-
 if __name__ == '__main__':
     unittest.main()