1 files changed, 23 insertions, 23 deletions

diff --git a/activemodel/lib/active_model/attribute_methods.rb b/activemodel/lib/active_model/attribute_methods.rb
index cc6285f932..888a431e5f 100644
--- a/activemodel/lib/active_model/attribute_methods.rb
+++ b/activemodel/lib/active_model/attribute_methods.rb
@@ -1,5 +1,6 @@
-require 'concurrent/map'
-require 'mutex_m'
+# frozen_string_literal: true
+
+require "concurrent/map"
 
 module ActiveModel
   # Raised when an attribute is not defined.
@@ -68,9 +69,8 @@ module ActiveModel
     CALL_COMPILABLE_REGEXP = /\A[a-zA-Z_]\w*[!?]?\z/
 
     included do
-      class_attribute :attribute_aliases, :attribute_method_matchers, instance_writer: false
-      self.attribute_aliases = {}
-      self.attribute_method_matchers = [ClassMethods::AttributeMethodMatcher.new]
+      class_attribute :attribute_aliases, instance_writer: false, default: {}
+      class_attribute :attribute_method_matchers, instance_writer: false, default: [ ClassMethods::AttributeMethodMatcher.new ]
     end
 
     module ClassMethods
@@ -289,7 +289,7 @@ module ActiveModel
             generate_method = "define_method_#{matcher.method_missing_target}"
 
             if respond_to?(generate_method, true)
-              send(generate_method, attr_name)
+              send(generate_method, attr_name.to_s)
             else
               define_proxy_call true, generated_attribute_methods, method_name, matcher.method_missing_target, attr_name.to_s
             end
@@ -328,18 +328,15 @@ module ActiveModel
         attribute_method_matchers_cache.clear
       end
 
-      def generated_attribute_methods #:nodoc:
-        @generated_attribute_methods ||= Module.new {
-          extend Mutex_m
-        }.tap { |mod| include mod }
-      end
+      private
+        def generated_attribute_methods
+          @generated_attribute_methods ||= Module.new.tap { |mod| include mod }
+        end
 
-      protected
-        def instance_method_already_implemented?(method_name) #:nodoc:
+        def instance_method_already_implemented?(method_name)
           generated_attribute_methods.method_defined?(method_name)
         end
 
-      private
         # The methods +method_missing+ and +respond_to?+ of this module are
         # invoked often in a typical rails, both of which invoke the method
         # +matched_attribute_method+. The latter method iterates through an
@@ -349,11 +346,11 @@ module ActiveModel
         # used to alleviate the GC, which ultimately also speeds up the app
         # significantly (in our case our test suite finishes 10% faster with
         # this cache).
-        def attribute_method_matchers_cache #:nodoc:
+        def attribute_method_matchers_cache
           @attribute_method_matchers_cache ||= Concurrent::Map.new(initial_capacity: 4)
         end
 
-        def attribute_method_matchers_matching(method_name) #:nodoc:
+        def attribute_method_matchers_matching(method_name)
           attribute_method_matchers_cache.compute_if_absent(method_name) do
             # Must try to match prefixes/suffixes first, or else the matcher with no prefix/suffix
             # will match every time.
@@ -365,8 +362,8 @@ module ActiveModel
         # Define a method `name` in `mod` that dispatches to `send`
         # using the given `extra` args. This falls back on `define_method`
         # and `send` if the given names cannot be compiled.
-        def define_proxy_call(include_private, mod, name, send, *extra) #:nodoc:
-          defn = if name =~ NAME_COMPILABLE_REGEXP
+        def define_proxy_call(include_private, mod, name, send, *extra)
+          defn = if NAME_COMPILABLE_REGEXP.match?(name)
             "def #{name}(*args)"
           else
             "define_method(:'#{name}') do |*args|"
@@ -374,7 +371,7 @@ module ActiveModel
 
           extra = (extra.map!(&:inspect) << "*args").join(", ".freeze)
 
-          target = if send =~ CALL_COMPILABLE_REGEXP
+          target = if CALL_COMPILABLE_REGEXP.match?(send)
             "#{"self." unless include_private}#{send}(#{extra})"
           else
             "send(:'#{send}', #{extra})"
@@ -393,7 +390,7 @@ module ActiveModel
           AttributeMethodMatch = Struct.new(:target, :attr_name, :method_name)
 
           def initialize(options = {})
-            @prefix, @suffix = options.fetch(:prefix, ''), options.fetch(:suffix, '')
+            @prefix, @suffix = options.fetch(:prefix, ""), options.fetch(:suffix, "")
             @regex = /^(?:#{Regexp.escape(@prefix)})(.*)(?:#{Regexp.escape(@suffix)})$/
             @method_missing_target = "#{@prefix}attribute#{@suffix}"
             @method_name = "#{prefix}%s#{suffix}"
@@ -458,12 +455,11 @@ module ActiveModel
       end
     end
 
-    protected
-      def attribute_method?(attr_name) #:nodoc:
+    private
+      def attribute_method?(attr_name)
         respond_to_without_attributes?(:attributes) && attributes.include?(attr_name)
       end
 
-    private
       # Returns a struct representing the matching attribute method.
       # The struct's attributes are prefix, base and suffix.
       def matched_attribute_method(method_name)
@@ -474,5 +470,9 @@ module ActiveModel
       def missing_attribute(attr_name, stack)
         raise ActiveModel::MissingAttributeError, "missing attribute: #{attr_name}", stack
       end
+
+      def _read_attribute(attr)
+        __send__(attr)
+      end
   end
 end