arity_coerce

# File activesupport/lib/active_support/deprecation/behaviors.rb, line 109
        def arity_coerce(behavior)
          unless behavior.respond_to?(:call)
            raise ArgumentError, "#{behavior.inspect} is not a valid deprecation behavior."
          end

          if behavior.arity == 4 || behavior.arity == -1
            behavior
          else
            -> message, callstack, _, _ { behavior.call(message, callstack) }
          end
        end