This method is deprecated or moved on the latest stable version. The last existing version (v2.3.8) is shown here.
attribute_will_change!(attr)
Handle *_will_change! for method_missing.
# File activerecord/lib/active_record/dirty.rb, line 121 def attribute_will_change!(attr) changed_attributes[attr] = clone_attribute_value(:read_attribute, attr) end
