Improve code following Rubocop's suggestions

lib/enumerate_it/base.rb

@@ -82,41 +82,43 @@ def self.to_range
       (list.min..list.max)
     end
 
-    private
+    class << self
+      def translate(value)
+        return value unless value.is_a? Symbol
 
-    def self.sorted_map
-      return enumeration if sort_mode == :none
+        default = value.to_s.gsub(/_/, ' ').split.map(&:capitalize).join(' ')
+        I18n.t("enumerations.#{self.name.underscore}.#{value.to_s.underscore}", default: default)
+      end
 
-      enumeration.sort_by { |k, v| sort_lambda.call(k, v) }
-    end
+      private
 
-    def self.sort_lambda
-      {
-        value:       lambda { |_k, v| v[0] },
-        name:        lambda { |k, _v| k },
-        translation: lambda { |_k, v| translate(v[1]) }
-      }[sort_mode || :translation]
-    end
+      def sorted_map
+        return enumeration if sort_mode == :none
 
-    def self.translate(value)
-      return value unless value.is_a? Symbol
+        enumeration.sort_by { |k, v| sort_lambda.call(k, v) }
+      end
 
-      default = value.to_s.gsub(/_/, ' ').split.map(&:capitalize).join(' ')
-      I18n.t("enumerations.#{self.name.underscore}.#{value.to_s.underscore}", default: default)
-    end
+      def sort_lambda
+        {
+          value:       lambda { |_k, v| v[0] },
+          name:        lambda { |k, _v| k },
+          translation: lambda { |_k, v| translate(v[1]) }
+        }[sort_mode || :translation]
+      end
 
-    def self.normalize_enumeration(values_hash)
-      values_hash.each_pair do |key, value|
-        values_hash[key] = [value, key] unless value.is_a? Array
+      def normalize_enumeration(values_hash)
+        values_hash.each_pair do |key, value|
+          values_hash[key] = [value, key] unless value.is_a? Array
+        end
       end
-    end
 
-    def self.register_enumeration(values_hash)
-      @@registered_enumerations[self] = values_hash
-    end
+      def register_enumeration(values_hash)
+        @@registered_enumerations[self] = values_hash
+      end
 
-    def self.define_enumeration_constant(name, value)
-      const_set name.to_s.gsub(/-/, '_').upcase, value
+      def define_enumeration_constant(name, value)
+        const_set name.to_s.gsub(/-/, '_').upcase, value
+      end
     end
   end
 end

spec/enumerate_it/base_spec.rb

@@ -49,7 +49,7 @@
         it { should eq(%w(1 2 3 0)) }
       end
     end
- end
+  end
 
   it "creates a method that returns the enumeration specification" do
     expect(TestEnumeration.enumeration).to eq(
@@ -234,8 +234,8 @@ class ActiveRecordStub
         attr_accessor :bla
 
         class << self
-          def validates_inclusion_of(options); true; end
-          def validates_presence_of; true; end
+          def validates_inclusion_of(_); true; end
+          def validates_presence_of;     true; end
         end
       end