* lib/rdoc.rb, lib/rdoc, test/rdoc: Update to RDoc 4.2.0.alpha(313287)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47391 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rdoc/i18n/locale.rb

@@ -0,0 +1,101 @@
+##
+# A message container for a locale.
+#
+# This object provides the following two features:
+#
+#   * Loads translated messages from .po file.
+#   * Translates a message into the locale.
+
+class RDoc::I18n::Locale
+
+  @@locales = {} # :nodoc:
+
+  class << self
+
+    ##
+    # Returns the locale object for +locale_name+.
+
+    def [](locale_name)
+      @@locales[locale_name] ||= new(locale_name)
+    end
+
+    ##
+    # Sets the locale object for +locale_name+.
+    #
+    # Normally, this method is not used. This method is useful for
+    # testing.
+
+    def []=(locale_name, locale)
+      @@locales[locale_name] = locale
+    end
+
+  end
+
+  ##
+  # The name of the locale. It uses IETF language tag format
+  # +[language[_territory][.codeset][@modifier]]+.
+  #
+  # See also {BCP 47 - Tags for Identifying
+  # Languages}[http://tools.ietf.org/rfc/bcp/bcp47.txt].
+
+  attr_reader :name
+
+  ##
+  # Creates a new locale object for +name+ locale. +name+ must
+  # follow IETF language tag format.
+
+  def initialize(name)
+    @name = name
+    @messages = {}
+  end
+
+  ##
+  # Loads translation messages from +locale_directory+/+@name+/rdoc.po
+  # or +locale_directory+/+@name+.po. The former has high priority.
+  #
+  # This method requires gettext gem for parsing .po file. If you
+  # don't have gettext gem, this method doesn't load .po file. This
+  # method warns and returns +false+.
+  #
+  # Returns +true+ if succeeded, +false+ otherwise.
+
+  def load(locale_directory)
+    return false if @name.nil?
+
+    po_file_candidates = [
+      File.join(locale_directory, @name, 'rdoc.po'),
+      File.join(locale_directory, "#{@name}.po"),
+    ]
+    po_file = po_file_candidates.find do |po_file_candidate|
+      File.exist?(po_file_candidate)
+    end
+    return false unless po_file
+
+    begin
+      require 'gettext/po_parser'
+      require 'gettext/mo'
+    rescue LoadError
+      warn('Need gettext gem for i18n feature:')
+      warn('  gem install gettext')
+      return false
+    end
+
+    po_parser = GetText::POParser.new
+    messages = GetText::MO.new
+    po_parser.report_warning = false
+    po_parser.parse_file(po_file, messages)
+
+    @messages.merge!(messages)
+
+    true
+  end
+
+  ##
+  # Translates the +message+ into locale. If there is no tranlsation
+  # messages for +message+ in locale, +message+ itself is returned.
+
+  def translate(message)
+    @messages[message] || message
+  end
+
+end