3 files changed, 3 insertions, 3 deletions
diff --git a/activemodel/lib/active_model/attribute_methods.rb b/activemodel/lib/active_model/attribute_methods.rb
index 286cd6c206..9033ec0dca 100644
--- a/activemodel/lib/active_model/attribute_methods.rb
+++ b/activemodel/lib/active_model/attribute_methods.rb
@@ -372,7 +372,7 @@ module ActiveModel
             "define_method(:'#{name}') do |*args|"
           end
 
-          extra = (extra.map!(&:inspect) << "*args").join(", ")
+          extra = (extra.map!(&:inspect) << "*args").join(", ".freeze)
 
           target = if send =~ CALL_COMPILABLE_REGEXP
             "#{"self." unless include_private}#{send}(#{extra})"
diff --git a/activemodel/lib/active_model/naming.rb b/activemodel/lib/active_model/naming.rb
index 1f1749af4e..213f2d5b6a 100644
--- a/activemodel/lib/active_model/naming.rb
+++ b/activemodel/lib/active_model/naming.rb
@@ -192,7 +192,7 @@ module ActiveModel
     private
 
     def _singularize(string)
-      ActiveSupport::Inflector.underscore(string).tr('/', '_')
+      ActiveSupport::Inflector.underscore(string).tr('/'.freeze, '_'.freeze)
     end
   end
 
diff --git a/activemodel/lib/active_model/validations/validates.rb b/activemodel/lib/active_model/validations/validates.rb
index bda436d8d0..1da4df21e7 100644
--- a/activemodel/lib/active_model/validations/validates.rb
+++ b/activemodel/lib/active_model/validations/validates.rb
@@ -115,7 +115,7 @@ module ActiveModel
           key = "#{key.to_s.camelize}Validator"
 
           begin
-            validator = key.include?('::') ? key.constantize : const_get(key)
+            validator = key.include?('::'.freeze) ? key.constantize : const_get(key)
           rescue NameError
             raise ArgumentError, "Unknown validator: '#{key}'"
           end