vendor/rails/activesupport/lib/active_support/multibyte/unicode_database.rb

   1 # encoding: utf-8
   2
   3 module ActiveSupport #:nodoc:
   4   module Multibyte #:nodoc:
   5     # Holds data about a codepoint in the Unicode database
   6     class Codepoint
   7       attr_accessor :code, :combining_class, :decomp_type, :decomp_mapping, :uppercase_mapping, :lowercase_mapping
   8     end
   9
  10     # Holds static data from the Unicode database
  11     class UnicodeDatabase
  12       ATTRIBUTES = :codepoints, :composition_exclusion, :composition_map, :boundary, :cp1252
  13
  14       attr_writer(*ATTRIBUTES)
  15
  16       def initialize
  17         @codepoints = Hash.new(Codepoint.new)
  18         @composition_exclusion = []
  19         @composition_map = {}
  20         @boundary = {}
  21         @cp1252 = {}
  22       end
  23
  24       # Lazy load the Unicode database so it's only loaded when it's actually used
  25       ATTRIBUTES.each do |attr_name|
  26         class_eval(<<-EOS, __FILE__, __LINE__)
  27           def #{attr_name}
  28             load
  29             @#{attr_name}
  30           end
  31         EOS
  32       end
  33
  34       # Loads the Unicode database and returns all the internal objects of UnicodeDatabase.
  35       def load
  36         begin
  37           @codepoints, @composition_exclusion, @composition_map, @boundary, @cp1252 = File.open(self.class.filename, 'rb') { |f| Marshal.load f.read }
  38         rescue Exception => e
  39             raise IOError.new("Couldn't load the Unicode tables for UTF8Handler (#{e.message}), ActiveSupport::Multibyte is unusable")
  40         end
  41
  42         # Redefine the === method so we can write shorter rules for grapheme cluster breaks
  43         @boundary.each do |k,_|
  44           @boundary[k].instance_eval do
  45             def ===(other)
  46               detect { |i| i === other } ? true : false
  47             end
  48           end if @boundary[k].kind_of?(Array)
  49         end
  50
  51         # define attr_reader methods for the instance variables
  52         class << self
  53           attr_reader(*ATTRIBUTES)
  54         end
  55       end
  56
  57       # Returns the directory in which the data files are stored
  58       def self.dirname
  59         File.dirname(__FILE__) + '/../values/'
  60       end
  61
  62       # Returns the filename for the data file for this version
  63       def self.filename
  64         File.expand_path File.join(dirname, "unicode_tables.dat")
  65       end
  66     end
  67
  68     # UniCode Database
  69     UCD = UnicodeDatabase.new
  70   end
  71 end