Merge branch 'master' into pr/539

Conflicts:
	mongoengine/base/datastructures.py

mongoengine/base/datastructures.py

@@ -1,4 +1,6 @@
 import weakref
+import functools
+import itertools
 from mongoengine.common import _import_class
 
 __all__ = ("BaseDict", "BaseList")
@@ -183,3 +185,97 @@ class BaseList(list):
                 self._instance._mark_as_changed('%s.%s' % (self._name, key))
             else:
                 self._instance._mark_as_changed(self._name)
+
+
+class StrictDict(object):
+    __slots__ = ()
+    _special_fields = set(['get', 'pop', 'iteritems', 'items', 'keys', 'create'])
+    _classes = {}
+    def __init__(self, **kwargs):
+        for k,v in kwargs.iteritems():
+            setattr(self, k, v)
+    def __getitem__(self, key):
+        key = '_reserved_' + key if key in self._special_fields else key
+        try:
+            return getattr(self, key)
+        except AttributeError:
+            raise KeyError(key)
+    def __setitem__(self, key, value):
+        key = '_reserved_' + key if key in self._special_fields else key
+        return setattr(self, key, value)
+    def __contains__(self, key):
+        return hasattr(self, key)
+    def get(self, key, default=None):
+        try:
+            return self[key]
+        except KeyError:
+            return default
+    def pop(self, key, default=None):
+        v = self.get(key, default)
+        try:
+            delattr(self, key)
+        except AttributeError:
+            pass
+        return v
+    def iteritems(self):
+        for key in self:
+            yield key, self[key]
+    def items(self):
+        return [(k, self[k]) for k in iter(self)]
+    def keys(self):
+        return list(iter(self))
+    def __iter__(self):
+        return (key for key in self.__slots__ if hasattr(self, key))
+    def __len__(self):
+        return len(list(self.iteritems()))
+    def __eq__(self, other):
+        return self.items() == other.items()
+    def __neq__(self, other):
+        return self.items() != other.items()
+
+    @classmethod
+    def create(cls, allowed_keys):
+        allowed_keys_tuple = tuple(('_reserved_' + k if k in cls._special_fields else k) for k in allowed_keys)
+        allowed_keys = frozenset(allowed_keys_tuple)
+        if allowed_keys not in cls._classes:
+            class SpecificStrictDict(cls):
+                __slots__ = allowed_keys_tuple
+            cls._classes[allowed_keys] = SpecificStrictDict
+        return cls._classes[allowed_keys]
+
+
+class SemiStrictDict(StrictDict):
+    __slots__ = ('_extras')
+    _classes = {}
+    def __getattr__(self, attr):
+        try:
+            super(SemiStrictDict, self).__getattr__(attr)
+        except AttributeError:
+            try:
+                return self.__getattribute__('_extras')[attr]
+            except KeyError as e:
+                raise AttributeError(e)
+    def __setattr__(self, attr, value):
+        try:
+            super(SemiStrictDict, self).__setattr__(attr, value)
+        except AttributeError:
+            try:
+                self._extras[attr] = value
+            except AttributeError:
+                self._extras = {attr: value}
+
+    def __delattr__(self, attr):
+        try:
+            super(SemiStrictDict, self).__delattr__(attr)
+        except AttributeError:
+            try:
+                del self._extras[attr]
+            except KeyError as e:
+                raise AttributeError(e)
+
+    def __iter__(self):
+        try:
+            extras_iter = iter(self.__getattribute__('_extras'))
+        except AttributeError:
+            extras_iter = ()
+        return itertools.chain(super(SemiStrictDict, self).__iter__(), extras_iter)