Multibyte strings respond_to the String methods they proxy so they can be duck-typed. Closes #6549.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6882 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/CHANGELOG

@@ -1,5 +1,7 @@
 *SVN*
 
+* Multibyte strings respond_to the String methods they proxy so they can be duck-typed.  #6549 [Tuxie]
+
 * Array#to_xml yields the builder just like Hash and ActiveRecord::Base.  #8472 [seth]
 
 * Date, Time, and DateTime support formatting blocks in addition to strftime strings. Introduce :long_ordinal format, e.g. "February 21st, 2005".  #8191 [Coda Hale]
@@ -146,7 +148,7 @@
 
 * Make String#chars slicing behaviour consistent with String. Closes #6387 [Manfred Stienstra]
 
-* Pull in latest multibye patch. Closes #6346 [Manfred Stienstra]
+* Pull in latest multibyte patch. Closes #6346 [Manfred Stienstra]
 
 * Add ActiveSupport::Multibyte.  Provides String#chars which lets you deal with strings as a sequence of chars, not of bytes. Closes #6242 [Julian Tarkhanov, Manfred Stienstra, Thijs van der Vossen & Jan Behrens]
 

activesupport/lib/active_support/multibyte/chars.rb

@@ -41,6 +41,12 @@ module ActiveSupport::Multibyte #:nodoc:
       @string
     end
     
+    # Make duck-typing with String possible
+    def respond_to?(method)
+      super || @string.respond_to?(method) || handler.respond_to?(method) ||
+        (method.to_s =~ /(.*)!/ && handler.respond_to?($1)) || false
+    end
+    
     # Create a new Chars instance.
     def initialize(str)
       @string = str.respond_to?(:string) ? str.string : str

activesupport/test/multibyte_chars_test.rb

@@ -151,6 +151,13 @@ class CharsTest < Test::Unit::TestCase
     end
   end
   
+  def test_duck_typing
+    assert_equal true,  'test'.chars.respond_to?(:strip)
+    assert_equal true,  'test'.chars.respond_to?(:normalize)
+    assert_equal true,  'test'.chars.respond_to?(:normalize!)
+    assert_equal false, 'test'.chars.respond_to?(:a_method_that_doesnt_exist)
+  end
+  
   protected
 
   def with_kcode(kcode)