1  # encoding: utf-8
   2 
   3  module ActiveSupport #:nodoc:
   4    module Multibyte #:nodoc:
   5      if Kernel.const_defined?(:Encoding)
   6        # Returns a regular expression that matches valid characters in the current encoding
   7        def self.valid_character
   8          VALID_CHARACTER[Encoding.default_external.to_s]
   9        end
  10      else
  11        def self.valid_character
  12          case $KCODE
  13          when 'UTF8'
  14            VALID_CHARACTER['UTF-8']
  15          when 'SJIS'
  16            VALID_CHARACTER['Shift_JIS']
  17          end
  18        end
  19      end
  20 
  21      if 'string'.respond_to?(:valid_encoding?)
  22        # Verifies the encoding of a string
  23        def self.verify(string)
  24          string.valid_encoding?
  25        end
  26      else
  27        def self.verify(string)
  28          if expression = valid_character
  29            # Splits the string on character boundaries, which are determined based on $KCODE.
  30            string.split(//).all? { |c| expression =~ c }
  31          else
  32            true
  33          end
  34        end
  35      end
  36 
  37      # Verifies the encoding of the string and raises an exception when it's not valid
  38      def self.verify!(string)
  39        raise EncodingError.new("Found characters with invalid encoding") unless verify(string)
  40      end
  41 
  42      if 'string'.respond_to?(:force_encoding)
  43        # Removes all invalid characters from the string.
  44        #
  45        # Note: this method is a no-op in Ruby 1.9
  46        def self.clean(string)
  47          string
  48        end
  49      else
  50        def self.clean(string)
  51          if expression = valid_character
  52            # Splits the string on character boundaries, which are determined based on $KCODE.
  53            string.split(//).grep(expression).join
  54          else
  55            string
  56          end
  57        end
  58      end
  59    end
  60  end