Active Null Object
Instead of returning nil when an association is not found, return a Null Object.
Associations
# Automatically searches for the Null Object based on the association name (NullUser)...
belongs_to :user, null_object: true
# ...or pass explicit class name.
belongs_to :user, null_object: 'NullAdmin'Finder
# Use a specialized finder if you want a Null Object if the record is not found.
User.find_or_null_object(1)
# ...or pass explicit class name.
User.find_or_null_object(1, null_object: 'NullAdmin')