Minor refactor to increase readability of method missing

.rubocop.yml

@@ -1,18 +1 @@
-# This configuration was generated by
-# `rubocop --auto-gen-config`
-# on 2016-09-19 23:23:44 -0400 using RuboCop version 0.43.0.
-# The point is for the user to remove these configuration records
-# one by one as the offenses are removed from the code base.
-# Note that changes in the inspected code, or installation of new
-# versions of RuboCop, may require this file to be generated again.
-
-# Offense count: 1
-# Configuration parameters: CountComments.
-Metrics/ClassLength:
-  Max: 101
-
-# Offense count: 64
-# Configuration parameters: AllowHeredoc, AllowURI, URISchemes.
-# URISchemes: http, https
-Metrics/LineLength:
-  Max: 483
+inherit_from: .rubocop_todo.yml

.rubocop_todo.yml

@@ -0,0 +1,52 @@
+# This configuration was generated by
+# `rubocop --auto-gen-config`
+# on 2016-09-19 23:29:07 -0400 using RuboCop version 0.43.0.
+# The point is for the user to remove these configuration records
+# one by one as the offenses are removed from the code base.
+# Note that changes in the inspected code, or installation of new
+# versions of RuboCop, may require this file to be generated again.
+# Offense count: 1
+# Configuration parameters: CountComments.
+Metrics/ClassLength:
+  Max: 101
+
+# Offense count: 64
+# Configuration parameters: AllowHeredoc, AllowURI, URISchemes.
+# URISchemes: http, https
+Metrics/LineLength:
+  Max: 483
+
+# Offense count: 1
+Metrics/AbcSize:
+  Max: 19
+
+# Offense count: 1
+Style/CaseEquality:
+  Exclude:
+    - 'lib/countries/country/class_methods.rb'
+
+# Offense count: 7
+Style/ClassVars:
+  Exclude:
+    - 'lib/countries/data.rb'
+
+# Offense count: 9
+Style/Documentation:
+  Exclude:
+    - 'spec/**/*'
+    - 'test/**/*'
+    - 'lib/countries/configuration.rb'
+    - 'lib/countries/country.rb'
+    - 'lib/countries/country/class_methods.rb'
+    - 'lib/countries/country/emoji.rb'
+    - 'lib/countries/global.rb'
+    - 'lib/countries/kwarg_struct.rb'
+    - 'lib/countries/mongoid.rb'
+
+
+# Offense count: 1
+# Configuration parameters: EnforcedStyle, SupportedStyles.
+# SupportedStyles: snake_case, camelCase
+Style/MethodName:
+  Exclude:
+    - 'lib/countries/country/class_methods.rb'

lib/countries/country/class_methods.rb

@@ -11,6 +11,8 @@ def self::Country(country_data_or_country)
   end
 
   module CountryClassMethods
+    FIND_BY_REGEX = /^find_(all_)?(country_|countries_)?by_(.+)/
+
     def new(country_data)
       super if country_data.is_a?(Hash) || codes.include?(country_data.to_s.upcase)
     end
@@ -47,25 +49,36 @@ def [](query)
       search(query)
     end
 
-    def method_missing(*m)
-      regex = m.first.to_s.match(/^find_(all_)?(country_|countries_)?by_(.+)/)
-      super unless regex
+    def method_missing(method_name, *arguments)
+      matches = method_name.to_s.match(FIND_BY_REGEX)
+      return_all = matches[1]
+      super unless matches
+
+      countries = find_by(matches[3], arguments[0], matches[2])
+      return_all ? countries : countries.last
+    end
 
-      countries = find_by(Regexp.last_match[3], m[1], Regexp.last_match[2])
-      Regexp.last_match[1] ? countries : countries.last
+    def respond_to_missing?(method_name, include_private = false)
+      matches = method_name.to_s.match(FIND_BY_REGEX)
+      if matches && matches[3]
+        matches[3].all? { |a| instance_methods.include?(a.to_sym) }
+      else
+        super
+      end
     end
 
     def find_all_by(attribute, val)
-      attributes, value = parse_attributes(attribute, val)
+      attributes, lookup_value = parse_attributes(attribute, val)
 
       ISO3166::Data.cache.select do |_, v|
-        attributes.map do |attr|
-          Array(Country.new(v).send(attr)).any? { |n| value === sterlize_value(n) }
-        end.include?(true)
+        country = Country.new(v)
+        attributes.any? do |attr|
+          Array(country.send(attr)).any? { |n| lookup_value === strip_accents(n) }
+        end
       end
     end
 
-    def sterlize_value(v)
+    def strip_accents(v)
       if v.is_a?(Regexp)
         Regexp.new(v.source.unaccent, 'i')
       else
@@ -85,7 +98,7 @@ def parse_attributes(attribute, val)
         # attributes << 'translated_names'
       end
 
-      [attributes, sterlize_value(val)]
+      [attributes, strip_accents(val)]
     end
 
     def find_by(attribute, value, obj = nil)