module ActiveRecord::AttributeDecorators::ClassMethods

def add_user_provided_columns(*)
  super.map do |column|
    decorated_type = attribute_type_decorations.apply(column.name, column.cast_type)
    column.with_type(decorated_type)
  end
end

def decorate_attribute_type(column_name, decorator_name, &block)
  matcher = ->(name, _) { name == column_name.to_s }
  key = "_#{column_name}_#{decorator_name}"
  decorate_matching_attribute_types(matcher, key, &block)
end

def decorate_matching_attribute_types(matcher, decorator_name, &block)
  clear_caches_calculated_from_columns
  decorator_name = decorator_name.to_s
  # Create new hashes so we don't modify parent classes
  self.attribute_type_decorations = attribute_type_decorations.merge(decorator_name => [matcher, block])
end