mirror of
https://github.com/sqlalchemy/sqlalchemy.git
synced 2026-06-08 08:36:48 -04:00
752f2e0fc8
implicitly initialized to None via first access; this action, which has always resulted in a population of the attribute, now emits an attribute event just like any other attribute set operation and generates the same kind of history as one. Additionally, many mapper internal operations will no longer implicitly generate these "None" values when various never-set attributes are checked. These are subtle behavioral fixes to attribute mechanics which provide a better solution to the problem of 🎫`3060`, which also involves recognition of attributes explicitly set to ``None`` vs. attributes that were never set. fixes #3061