Module: RDoc::Encoding

Relationships & Source Files
Defined in:	lib/rdoc/encoding.rb

Overview

This class is a wrapper around File IO and Encoding that helps RDoc load files and convert them to the correct encoding.

Class Method Summary

.change_encoding(text, encoding)

Changes encoding based on encoding without converting and returns new string.
.read_file(filename, encoding, force_transcode = false)

Reads the contents of filename and handles any encoding directives in the file.
.remove_frozen_string_literal(string)
.set_encoding(string)

Sets the encoding of string based on the magic comment.

Class Method Details

.change_encoding(text, encoding)

Changes encoding based on encoding without converting and returns new string

[ GitHub ]

# File 'lib/rdoc/encoding.rb', line 117


def self.change_encoding text, encoding
  if text.kind_of? RDoc::Comment
    text.encode! encoding
  else
    # TODO: Remove this condition after Ruby 2.2 EOL
    if RUBY_VERSION < '2.3.0'
      text.force_encoding encoding
    else
      String.new text, encoding: encoding
    end
  end
end

.read_file(filename, encoding, force_transcode = false)

Reads the contents of filename and handles any encoding directives in the file.

The content will be converted to the encoding. If the file cannot be converted a warning will be printed and nil will be returned.

If force_transcode is true the document will be transcoded and any unknown character in the target encoding will be replaced with '?'

[ GitHub ]

# File 'lib/rdoc/encoding.rb', line 20


def self.read_file filename, encoding, force_transcode = false
  content = open filename, "rb" do |f| f.read end
  content.gsub!("\r\n", "\n") if RUBY_PLATFORM =~ /mswin|mingw/

  utf8 = content.sub!(/\A\xef\xbb\xbf/, '')

  content = RDoc::Encoding.set_encoding content

  begin
    encoding ||= Encoding.default_external
    orig_encoding = content.encoding

    if not orig_encoding.ascii_compatible? then
      content = content.encode encoding
    elsif utf8 then
      content = RDoc::Encoding.change_encoding content, Encoding::UTF_8
      content = content.encode encoding
    else
      # assume the content is in our output encoding
      content = RDoc::Encoding.change_encoding content, encoding
    end

    unless content.valid_encoding? then
      # revert and try to transcode
      content = RDoc::Encoding.change_encoding content, orig_encoding
      content = content.encode encoding
    end

    unless content.valid_encoding? then
      warn "unable to convert #{filename} to #{encoding}, skipping"
      content = nil
    end
  rescue Encoding::InvalidByteSequenceError,
         Encoding::UndefinedConversionError => e
    if force_transcode then
      content = RDoc::Encoding.change_encoding content, orig_encoding
      content = content.encode(encoding,
                               :invalid => :replace,
                               :undef => :replace,
                               :replace => '?')
      return content
    else
      warn "unable to convert #{e.message} for #{filename}, skipping"
      return nil
    end
  end

  content
rescue ArgumentError => e
  raise unless e.message =~ /unknown encoding name - (.*)/
  warn "unknown encoding name \"#{$1}\" for #{filename}, skipping"
  nil
rescue Errno::EISDIR, Errno::ENOENT
  nil
end

.remove_frozen_string_literal(string)

[ GitHub ]

# File 'lib/rdoc/encoding.rb', line 76


def self.remove_frozen_string_literal string
  string =~ /\A(?:#!.*\n)?(.*\n)/
  first_line = $1

  if first_line =~ /\A# frozen[-_]string[-_]literal[=:].$/i
    string = string.sub first_line, ''
  end

  string
end

.set_encoding(string)

Sets the encoding of string based on the magic comment

[ GitHub ]

# File 'lib/rdoc/encoding.rb', line 90


def self.set_encoding string
  string = remove_frozen_string_literal string

  string =~ /\A(?:#!.*\n)?(.*\n)/

  first_line = $1

  name = case first_line
         when /^<\?xml[^?]*encoding=(["'])(.*?)\1/ then $2
         when /\b(?:en)?coding[=:]\s*([^\s;]+)/i   then $1
         else                                           return string
         end

  string = string.sub first_line, ''

  string = remove_frozen_string_literal string

  enc = Encoding.find name
  string = RDoc::Encoding.change_encoding string, enc if enc

  string
end