module ActiveSupport module Multibyte module Unicode extend self # A list of all available normalization forms. See http://www.unicode.org/reports/tr15/tr15-29.html for more # information about normalization. NORMALIZATION_FORMS = [:c, :kc, :d, :kd] # The Unicode version that is supported by the implementation UNICODE_VERSION = '5.2.0' # The default normalization used for operations that require normalization. It can be set to any of the # normalizations in NORMALIZATION_FORMS. # # Example: # ActiveSupport::Multibyte::Unicode.default_normalization_form = :c attr_accessor :default_normalization_form @default_normalization_form = :kc # Hangul character boundaries and properties HANGUL_SBASE = 0xAC00 HANGUL_LBASE = 0x1100 HANGUL_VBASE = 0x1161 HANGUL_TBASE = 0x11A7 HANGUL_LCOUNT = 19 HANGUL_VCOUNT = 21 HANGUL_TCOUNT = 28 HANGUL_NCOUNT = HANGUL_VCOUNT * HANGUL_TCOUNT HANGUL_SCOUNT = 11172 HANGUL_SLAST = HANGUL_SBASE + HANGUL_SCOUNT HANGUL_JAMO_FIRST = 0x1100 HANGUL_JAMO_LAST = 0x11FF # All the unicode whitespace WHITESPACE = [ (0x0009..0x000D).to_a, # White_Space # Cc [5] .. 0x0020, # White_Space # Zs SPACE 0x0085, # White_Space # Cc 0x00A0, # White_Space # Zs NO-BREAK SPACE 0x1680, # White_Space # Zs OGHAM SPACE MARK 0x180E, # White_Space # Zs MONGOLIAN VOWEL SEPARATOR (0x2000..0x200A).to_a, # White_Space # Zs [11] EN QUAD..HAIR SPACE 0x2028, # White_Space # Zl LINE SEPARATOR 0x2029, # White_Space # Zp PARAGRAPH SEPARATOR 0x202F, # White_Space # Zs NARROW NO-BREAK SPACE 0x205F, # White_Space # Zs MEDIUM MATHEMATICAL SPACE 0x3000, # White_Space # Zs IDEOGRAPHIC SPACE ].flatten.freeze # BOM (byte order mark) can also be seen as whitespace, it's a non-rendering character used to distinguish # between little and big endian. This is not an issue in utf-8, so it must be ignored. LEADERS_AND_TRAILERS = WHITESPACE + [65279] # ZERO-WIDTH NO-BREAK SPACE aka BOM # Returns a regular expression pattern that matches the passed Unicode codepoints def self.codepoints_to_pattern(array_of_codepoints) #:nodoc: array_of_codepoints.collect{ |e| [e].pack 'U*' }.join('|') end TRAILERS_PAT = /(#{codepoints_to_pattern(LEADERS_AND_TRAILERS)})+\Z/u LEADERS_PAT = /\A(#{codepoints_to_pattern(LEADERS_AND_TRAILERS)})+/u # Unpack the string at codepoints boundaries. Raises an EncodingError when the encoding of the string isn't # valid UTF-8. # # Example: # Unicode.u_unpack('Café') #=> [67, 97, 102, 233] def u_unpack(string) begin string.unpack 'U*' rescue ArgumentError raise EncodingError, 'malformed UTF-8 character' end end # Detect whether the codepoint is in a certain character class. Returns +true+ when it's in the specified # character class and +false+ otherwise. Valid character classes are: :cr, :lf, :l, # :v, :lv, :lvt and :t. # # Primarily used by the grapheme cluster support. def in_char_class?(codepoint, classes) classes.detect { |c| database.boundary[c] === codepoint } ? true : false end # Unpack the string at grapheme boundaries. Returns a list of character lists. # # Example: # Unicode.g_unpack('क्षि') #=> [[2325, 2381], [2359], [2367]] # Unicode.g_unpack('Café') #=> [[67], [97], [102], [233]] def g_unpack(string) codepoints = u_unpack(string) unpacked = [] pos = 0 marker = 0 eoc = codepoints.length while(pos < eoc) pos += 1 previous = codepoints[pos-1] current = codepoints[pos] if ( # CR X LF one = ( previous == database.boundary[:cr] and current == database.boundary[:lf] ) or # L X (L|V|LV|LVT) two = ( database.boundary[:l] === previous and in_char_class?(current, [:l,:v,:lv,:lvt]) ) or # (LV|V) X (V|T) three = ( in_char_class?(previous, [:lv,:v]) and in_char_class?(current, [:v,:t]) ) or # (LVT|T) X (T) four = ( in_char_class?(previous, [:lvt,:t]) and database.boundary[:t] === current ) or # X Extend five = (database.boundary[:extend] === current) ) else unpacked << codepoints[marker..pos-1] marker = pos end end unpacked end # Reverse operation of g_unpack. # # Example: # Unicode.g_pack(Unicode.g_unpack('क्षि')) #=> 'क्षि' def g_pack(unpacked) (unpacked.flatten).pack('U*') end # Re-order codepoints so the string becomes canonical. def reorder_characters(codepoints) length = codepoints.length- 1 pos = 0 while pos < length do cp1, cp2 = database.codepoints[codepoints[pos]], database.codepoints[codepoints[pos+1]] if (cp1.combining_class > cp2.combining_class) && (cp2.combining_class > 0) codepoints[pos..pos+1] = cp2.code, cp1.code pos += (pos > 0 ? -1 : 1) else pos += 1 end end codepoints end # Decompose composed characters to the decomposed form. def decompose_codepoints(type, codepoints) codepoints.inject([]) do |decomposed, cp| # if it's a hangul syllable starter character if HANGUL_SBASE <= cp and cp < HANGUL_SLAST sindex = cp - HANGUL_SBASE ncp = [] # new codepoints ncp << HANGUL_LBASE + sindex / HANGUL_NCOUNT ncp << HANGUL_VBASE + (sindex % HANGUL_NCOUNT) / HANGUL_TCOUNT tindex = sindex % HANGUL_TCOUNT ncp << (HANGUL_TBASE + tindex) unless tindex == 0 decomposed.concat ncp # if the codepoint is decomposable in with the current decomposition type elsif (ncp = database.codepoints[cp].decomp_mapping) and (!database.codepoints[cp].decomp_type || type == :compatability) decomposed.concat decompose_codepoints(type, ncp.dup) else decomposed << cp end end end # Compose decomposed characters to the composed form. def compose_codepoints(codepoints) pos = 0 eoa = codepoints.length - 1 starter_pos = 0 starter_char = codepoints[0] previous_combining_class = -1 while pos < eoa pos += 1 lindex = starter_char - HANGUL_LBASE # -- Hangul if 0 <= lindex and lindex < HANGUL_LCOUNT vindex = codepoints[starter_pos+1] - HANGUL_VBASE rescue vindex = -1 if 0 <= vindex and vindex < HANGUL_VCOUNT tindex = codepoints[starter_pos+2] - HANGUL_TBASE rescue tindex = -1 if 0 <= tindex and tindex < HANGUL_TCOUNT j = starter_pos + 2 eoa -= 2 else tindex = 0 j = starter_pos + 1 eoa -= 1 end codepoints[starter_pos..j] = (lindex * HANGUL_VCOUNT + vindex) * HANGUL_TCOUNT + tindex + HANGUL_SBASE end starter_pos += 1 starter_char = codepoints[starter_pos] # -- Other characters else current_char = codepoints[pos] current = database.codepoints[current_char] if current.combining_class > previous_combining_class if ref = database.composition_map[starter_char] composition = ref[current_char] else composition = nil end unless composition.nil? codepoints[starter_pos] = composition starter_char = composition codepoints.delete_at pos eoa -= 1 pos -= 1 previous_combining_class = -1 else previous_combining_class = current.combining_class end else previous_combining_class = current.combining_class end if current.combining_class == 0 starter_pos = pos starter_char = codepoints[pos] end end end codepoints end # Replaces all ISO-8859-1 or CP1252 characters by their UTF-8 equivalent resulting in a valid UTF-8 string. # # Passing +true+ will forcibly tidy all bytes, assuming that the string's encoding is entirely CP1252 or ISO-8859-1. def tidy_bytes(string, force = false) if force return string.unpack("C*").map do |b| tidy_byte(b) end.flatten.compact.pack("C*").unpack("U*").pack("U*") end bytes = string.unpack("C*") conts_expected = 0 last_lead = 0 bytes.each_index do |i| byte = bytes[i] is_ascii = byte < 128 is_cont = byte > 127 && byte < 192 is_lead = byte > 191 && byte < 245 is_unused = byte > 240 is_restricted = byte > 244 # Impossible or highly unlikely byte? Clean it. if is_unused || is_restricted bytes[i] = tidy_byte(byte) elsif is_cont # Not expecting contination byte? Clean up. Otherwise, now expect one less. conts_expected == 0 ? bytes[i] = tidy_byte(byte) : conts_expected -= 1 else if conts_expected > 0 # Expected continuation, but got ASCII or leading? Clean backwards up to # the leading byte. (1..(i - last_lead)).each {|j| bytes[i - j] = tidy_byte(bytes[i - j])} conts_expected = 0 end if is_lead # Final byte is leading? Clean it. if i == bytes.length - 1 bytes[i] = tidy_byte(bytes.last) else # Valid leading byte? Expect continuations determined by position of # first zero bit, with max of 3. conts_expected = byte < 224 ? 1 : byte < 240 ? 2 : 3 last_lead = i end end end end bytes.empty? ? "" : bytes.flatten.compact.pack("C*").unpack("U*").pack("U*") end # Returns the KC normalization of the string by default. NFKC is considered the best normalization form for # passing strings to databases and validations. # # * string - The string to perform normalization on. # * form - The form you want to normalize in. Should be one of the following: # :c, :kc, :d, or :kd. Default is # ActiveSupport::Multibyte.default_normalization_form def normalize(string, form=nil) form ||= @default_normalization_form # See http://www.unicode.org/reports/tr15, Table 1 codepoints = u_unpack(string) case form when :d reorder_characters(decompose_codepoints(:canonical, codepoints)) when :c compose_codepoints(reorder_characters(decompose_codepoints(:canonical, codepoints))) when :kd reorder_characters(decompose_codepoints(:compatability, codepoints)) when :kc compose_codepoints(reorder_characters(decompose_codepoints(:compatability, codepoints))) else raise ArgumentError, "#{form} is not a valid normalization variant", caller end.pack('U*') end def apply_mapping(string, mapping) #:nodoc: u_unpack(string).map do |codepoint| cp = database.codepoints[codepoint] if cp and (ncp = cp.send(mapping)) and ncp > 0 ncp else codepoint end end.pack('U*') end # Holds data about a codepoint in the Unicode database class Codepoint attr_accessor :code, :combining_class, :decomp_type, :decomp_mapping, :uppercase_mapping, :lowercase_mapping end # Holds static data from the Unicode database class UnicodeDatabase ATTRIBUTES = :codepoints, :composition_exclusion, :composition_map, :boundary, :cp1252 attr_writer(*ATTRIBUTES) def initialize @codepoints = Hash.new(Codepoint.new) @composition_exclusion = [] @composition_map = {} @boundary = {} @cp1252 = {} end # Lazy load the Unicode database so it's only loaded when it's actually used ATTRIBUTES.each do |attr_name| class_eval(<<-EOS, __FILE__, __LINE__ + 1) def #{attr_name} # def codepoints load # load @#{attr_name} # @codepoints end # end EOS end # Loads the Unicode database and returns all the internal objects of UnicodeDatabase. def load begin @codepoints, @composition_exclusion, @composition_map, @boundary, @cp1252 = File.open(self.class.filename, 'rb') { |f| Marshal.load f.read } rescue Exception => e raise IOError.new("Couldn't load the Unicode tables for UTF8Handler (#{e.message}), ActiveSupport::Multibyte is unusable") end # Redefine the === method so we can write shorter rules for grapheme cluster breaks @boundary.each do |k,_| @boundary[k].instance_eval do def ===(other) detect { |i| i === other } ? true : false end end if @boundary[k].kind_of?(Array) end # define attr_reader methods for the instance variables class << self attr_reader(*ATTRIBUTES) end end # Returns the directory in which the data files are stored def self.dirname File.dirname(__FILE__) + '/../values/' end # Returns the filename for the data file for this version def self.filename File.expand_path File.join(dirname, "unicode_tables.dat") end end private def tidy_byte(byte) if byte < 160 [database.cp1252[byte] || byte].pack("U").unpack("C*") elsif byte < 192 [194, byte] else [195, byte - 64] end end def database @database ||= UnicodeDatabase.new end end end end