1 files changed, 4 insertions, 4 deletions
diff --git a/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb b/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
index a77da573fe..bf175a8a70 100644
--- a/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
+++ b/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
@@ -19,9 +19,9 @@ class Module
   # The attribute name must be a valid method name in Ruby.
   #
   #   module Foo
-  #     mattr_reader :"1_Badname "
+  #     mattr_reader :"1_Badname"
   #   end
-  #   # => NameError: invalid attribute name
+  #   # => NameError: invalid attribute name: 1_Badname
   #
   # If you want to opt out the creation on the instance reader method, pass
   # <tt>instance_reader: false</tt> or <tt>instance_accessor: false</tt>.
@@ -53,7 +53,7 @@ class Module
   def mattr_reader(*syms)
     options = syms.extract_options!
     syms.each do |sym|
-      raise NameError.new("invalid attribute name: #{sym}") unless sym =~ /^[_A-Za-z]\w*$/
+      raise NameError.new("invalid attribute name: #{sym}") unless sym =~ /\A[_A-Za-z]\w*\z/
       class_eval(<<-EOS, __FILE__, __LINE__ + 1)
         @@#{sym} = nil unless defined? @@#{sym}
 
@@ -119,7 +119,7 @@ class Module
   def mattr_writer(*syms)
     options = syms.extract_options!
     syms.each do |sym|
-      raise NameError.new("invalid attribute name: #{sym}") unless sym =~ /^[_A-Za-z]\w*$/
+      raise NameError.new("invalid attribute name: #{sym}") unless sym =~ /\A[_A-Za-z]\w*\z/
       class_eval(<<-EOS, __FILE__, __LINE__ + 1)
         @@#{sym} = nil unless defined? @@#{sym}