Core Data: Migrating ignores manual mapping model (or fails migration) despite mapping model’s existence
Let's say you created a somewhat complex migration model. Among other things, let's say it includes entity migration policies (you know -- subclasses of NSEntityMigrationPolicy). However, Core Data ignores your manual migration model. Why, oh why? You can try looking into this by clicking on schema name in Xcode 4, picking the "Run" sidebar 'tab', [...]