module Addressable::IDNA

Constants

ACE_MAX_LENGTH

ACE_PREFIX

This module is loosely based on idn_actionmailer by Mick Staugaard, the unicode library by Yoshida Masato, and the punycode implementation by Kazuhiro Nishiyama. Most of the code was copied verbatim, but some reformatting was done, and some translation from C was done.

Without their code to work from as a base, we’d all still be relying on the presence of libidn. Which nobody ever seems to have installed.

Original sources: github.com/staugaard/idn_actionmailer www.yoshidam.net/Ruby.html#unicode rubyforge.org/frs/?group_id=2550

DISPLAY_CHANGING

Characters that change how a label displays without being visible themselves: controls, format characters such as bidi overrides and isolates, and default ignorable code points. libidn rejects most of them, but not those added to Unicode after the version it checks against, such as U+2066 to U+2069. Format characters that are also default ignorable are left out of the second set, since Ruby warns about a duplicated range in a character class.

NAMEPREP_PROHIBITED

Characters that nameprep doesn’t allow in a label (Section 5 of RFC 3491), or that it maps to nothing, so they can’t be in a label that toASCII produces. Some code points are in more than one table; they’re listed only under the first, since Ruby warns about a duplicated range in a character class.

PUNYCODE_BASE

PUNYCODE_DAMP

PUNYCODE_DELIMITER

PUNYCODE_INITIAL_BIAS

PUNYCODE_INITIAL_N

PUNYCODE_MAXINT

PUNYCODE_PRINT_ASCII

PUNYCODE_SKEW

PUNYCODE_TMAX

PUNYCODE_TMIN

UNICODE_DATA

UNICODE_DATA_CANONICAL

UNICODE_DATA_COMBINING_CLASS

UNICODE_DATA_COMPATIBILITY

UNICODE_DATA_EXCLUSION

UNICODE_DATA_LOWERCASE

UNICODE_DATA_TITLECASE

UNICODE_DATA_UPPERCASE

UNICODE_MAX_LENGTH

UTF8_REGEX

UTF8_REGEX_MULTIBYTE

Public Class Methods

to_ascii (value)

Source

# File lib/addressable/idna/native.rb, line 42
def self.to_ascii(value)
  value.to_s.split('.', -1).map do |segment|
    if segment.size > 0 && segment.size < 64
      IDN::Idna.toASCII(segment, IDN::Idna::ALLOW_UNASSIGNED)
    elsif segment.size >= 64
      segment
    else
      ''
    end
  end.join('.')
end

to_unicode (value)

Source

# File lib/addressable/idna/native.rb, line 63
def self.to_unicode(value)
  value.to_s.split('.', -1).map do |segment|
    if segment.size > 0 && segment.size < 64
      decoded = IDN::Idna.toUnicode(segment, IDN::Idna::ALLOW_UNASSIGNED)
      decoded =~ DISPLAY_CHANGING ? segment : decoded
    elsif segment.size >= 64
      segment
    else
      ''
    end
  end.join('.')
end

unicode_normalize_kc (value)

Source

# File lib/addressable/idna/native.rb, line 34
def unicode_normalize_kc(value)
  value.to_s.unicode_normalize(:nfkc)
end

@deprecated Use {String#unicode_normalize(:nfkc)} instead

Private Class Methods

lookup_unicode_lowercase (codepoint)

Source

# File lib/addressable/idna/pure.rb, line 188
def self.lookup_unicode_lowercase(codepoint)
  codepoint_data = UNICODE_DATA[codepoint]
  (codepoint_data ?
    (codepoint_data[UNICODE_DATA_LOWERCASE] || codepoint) :
    codepoint)
end

punycode_adapt (delta, numpoints, firsttime)

Source

# File lib/addressable/idna/pure.rb, line 4742
def self.punycode_adapt(delta, numpoints, firsttime)
  delta = firsttime ? delta / PUNYCODE_DAMP : delta >> 1
  # delta >> 1 is a faster way of doing delta / 2
  delta += delta / numpoints
  difference = PUNYCODE_BASE - PUNYCODE_TMIN

  k = 0
  while delta > (difference * PUNYCODE_TMAX) / 2
    delta /= difference
    k += PUNYCODE_BASE
  end

  k + (difference + 1) * delta / (delta + PUNYCODE_SKEW)
end

Bias adaptation method

punycode_basic? (codepoint)

Source

# File lib/addressable/idna/pure.rb, line 4710
def self.punycode_basic?(codepoint)
  codepoint < 0x80
end

punycode_decode (value)

Source

# File lib/addressable/idna/native.rb, line 28
def self.punycode_decode(value)
  IDN::Punycode.decode(value.to_s)
end

punycode_decode_digit (codepoint)

Source

# File lib/addressable/idna/pure.rb, line 4728
def self.punycode_decode_digit(codepoint)
  if codepoint >= 48 && codepoint <= 57
    codepoint - 22
  elsif codepoint >= 65 && codepoint <= 90
    codepoint - 65
  elsif codepoint >= 97 && codepoint <= 122
    codepoint - 97
  else
    PUNYCODE_BASE
  end
end

Returns the numeric value of a basic codepoint (for use in representing integers) in the range 0 to base - 1, or PUNYCODE_BASE if codepoint does not represent a value.

punycode_delimiter? (codepoint)

Source

# File lib/addressable/idna/pure.rb, line 4715
def self.punycode_delimiter?(codepoint)
  codepoint == PUNYCODE_DELIMITER
end

punycode_encode (value)

Source

# File lib/addressable/idna/native.rb, line 24
def self.punycode_encode(value)
  IDN::Punycode.encode(value.to_s)
end

punycode_encode_digit (d)

Source

# File lib/addressable/idna/pure.rb, line 4720
def self.punycode_encode_digit(d)
  d + 22 + 75 * ((d < 26) ? 1 : 0)
end

unicode_downcase (input)

Source

# File lib/addressable/idna/pure.rb, line 180
def self.unicode_downcase(input)
  input = input.to_s unless input.is_a?(String)
  unpacked = input.unpack("U*")
  unpacked.map! { |codepoint| lookup_unicode_lowercase(codepoint) }
  return unpacked.pack("U*")
end

Unicode aware downcase method.

@api private @param [String] input

The input string.

@return [String] The downcased result.