diff options
Diffstat (limited to 'lib/sqlalchemy/orm/attributes.py')
| -rw-r--r-- | lib/sqlalchemy/orm/attributes.py | 27 |
1 files changed, 15 insertions, 12 deletions
diff --git a/lib/sqlalchemy/orm/attributes.py b/lib/sqlalchemy/orm/attributes.py index 321ab7d6f..31c351bb0 100644 --- a/lib/sqlalchemy/orm/attributes.py +++ b/lib/sqlalchemy/orm/attributes.py @@ -653,8 +653,8 @@ class AttributeImpl(object): """ raise NotImplementedError() - def initialize(self, state, dict_): - """Initialize the given state's attribute with an empty value.""" + def _default_value(self, state, dict_): + """Produce an empty value for an uninitialized scalar attribute.""" value = None for fn in self.dispatch.init_scalar: @@ -710,8 +710,7 @@ class AttributeImpl(object): if not passive & INIT_OK: return NO_VALUE else: - # Return a new, empty value - return self.initialize(state, dict_) + return self._default_value(state, dict_) def append(self, state, dict_, value, initiator, passive=PASSIVE_OFF): self.set(state, dict_, value, initiator, passive=passive) @@ -1184,11 +1183,14 @@ class CollectionAttributeImpl(AttributeImpl): # del is a no-op if collection not present. del dict_[self.key] - def initialize(self, state, dict_): - """Initialize this attribute with an empty collection.""" + def _default_value(self, state, dict_): + """Produce an empty collection for an un-initialized attribute""" - _, user_data = self._initialize_collection(state) - dict_[self.key] = user_data + if self.key in state._empty_collections: + return state._empty_collections[self.key] + + adapter, user_data = self._initialize_collection(state) + adapter._set_empty(user_data) return user_data def _initialize_collection(self, state): @@ -1287,7 +1289,7 @@ class CollectionAttributeImpl(AttributeImpl): old = self.get(state, dict_, passive=PASSIVE_ONLY_PERSISTENT) if old is PASSIVE_NO_RESULT: - old = self.initialize(state, dict_) + old = self._default_value(state, dict_) elif old is orig_iterable: # ignore re-assignment of the current collection, as happens # implicitly with in-place operators (foo.collection |= other) @@ -1699,7 +1701,6 @@ class History(History): @classmethod def from_collection(cls, attribute, state, current): original = state.committed_state.get(attribute.key, _NO_HISTORY) - if current is NO_VALUE: return cls((), (), ()) @@ -1892,8 +1893,10 @@ def init_state_collection(state, dict_, key): """Initialize a collection attribute and return the collection adapter.""" attr = state.manager[key].impl - user_data = attr.initialize(state, dict_) - return attr.get_collection(state, dict_, user_data) + user_data = attr._default_value(state, dict_) + adapter = attr.get_collection(state, dict_, user_data) + adapter._reset_empty() + return adapter def set_committed_value(instance, key, value): |