validate_transformation

# File activestorage/lib/active_storage/transformers/image_processing_transformer.rb, line 38
        def validate_transformation(name, argument)
          if name.to_s == "combine_options"
            raise ArgumentError, <<~ERROR.squish
              Active Storage's ImageProcessing transformer doesn't support :combine_options,
              as it always generates a single command.
            ERROR
          end
        end