2 files changed, 10 insertions, 2 deletions
diff --git a/activesupport/lib/active_support/core_ext/string/filters.rb b/activesupport/lib/active_support/core_ext/string/filters.rb
index b88976eab2..7461d03acc 100644
--- a/activesupport/lib/active_support/core_ext/string/filters.rb
+++ b/activesupport/lib/active_support/core_ext/string/filters.rb
@@ -26,6 +26,7 @@ class String
   # Returns a new string with all occurrences of the patterns removed.
   #   str = "foo bar test"
   #   str.remove(" test")                 # => "foo bar"
+  #   str.remove(" test", /bar/)          # => "foo "
   #   str                                 # => "foo bar test"
   def remove(*patterns)
     dup.remove!(*patterns)
@@ -33,8 +34,8 @@ class String
 
   # Alters the string by removing all occurrences of the patterns.
   #   str = "foo bar test"
-  #   str.remove!(" test")                 # => "foo bar"
-  #   str                                  # => "foo bar"
+  #   str.remove!(" test", /bar/)         # => "foo "
+  #   str                                 # => "foo "
   def remove!(*patterns)
     patterns.each do |pattern|
       gsub! pattern, ""
diff --git a/activesupport/lib/active_support/core_ext/string/multibyte.rb b/activesupport/lib/active_support/core_ext/string/multibyte.rb
index 2eedd4fdb1..57d7f8d1e7 100644
--- a/activesupport/lib/active_support/core_ext/string/multibyte.rb
+++ b/activesupport/lib/active_support/core_ext/string/multibyte.rb
@@ -35,6 +35,13 @@ class String
     ActiveSupport::Multibyte.proxy_class.new(self)
   end
 
+  # Return +true+ if string has utf_8 encoding.
+  #
+  #   utf_8_str = "some string".encode "UTF-8"
+  #   iso_str = "some string".encode "ISO-8859-1"
+  #
+  #   utf_8_str.is_utf8? # => true
+  #   iso_str.is_utf8?   # => false
   def is_utf8?
     case encoding
     when Encoding::UTF_8