attribute_method_matcher

# File activemodel/lib/active_model/attribute_methods.rb, line 312
        def attribute_method_matcher(method_name) #:nodoc:
          if attribute_method_matchers_cache.key?(method_name)
            attribute_method_matchers_cache[method_name]
          else
            # Must try to match prefixes/suffixes first, or else the matcher with no prefix/suffix
            # will match every time.
            matchers = attribute_method_matchers.partition(&:plain?).reverse.flatten(1)
            match = nil
            matchers.detect { |method| match = method.match(method_name) }
            attribute_method_matchers_cache[method_name] = match
          end
        end