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 = "9.0.0" # The default normalization used for operations that require # normalization. It can be set to any of the normalizations # in NORMALIZATION_FORMS. # # 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 # 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. # # Unicode.unpack_graphemes('क्षि') # => [[2325, 2381], [2359], [2367]] # Unicode.unpack_graphemes('Café') # => [[67], [97], [102], [233]] def unpack_graphemes(string) codepoints = string.codepoints.to_a unpacked = [] pos = 0 marker = 0 eoc = codepoints.length while (pos < eoc) pos += 1 previous = codepoints[pos - 1] current = codepoints[pos] # See http://unicode.org/reports/tr29/#Grapheme_Cluster_Boundary_Rules should_break = if pos == eoc true # GB3. CR X LF elsif previous == database.boundary[:cr] && current == database.boundary[:lf] false # GB4. (Control|CR|LF) ÷ elsif previous && in_char_class?(previous, [:control, :cr, :lf]) true # GB5. ÷ (Control|CR|LF) elsif in_char_class?(current, [:control, :cr, :lf]) true # GB6. L X (L|V|LV|LVT) elsif database.boundary[:l] === previous && in_char_class?(current, [:l, :v, :lv, :lvt]) false # GB7. (LV|V) X (V|T) elsif in_char_class?(previous, [:lv, :v]) && in_char_class?(current, [:v, :t]) false # GB8. (LVT|T) X (T) elsif in_char_class?(previous, [:lvt, :t]) && database.boundary[:t] === current false # GB9. X (Extend | ZWJ) elsif in_char_class?(current, [:extend, :zwj]) false # GB9a. X SpacingMark elsif database.boundary[:spacingmark] === current false # GB9b. Prepend X elsif database.boundary[:prepend] === previous false # GB10. (E_Base | EBG) Extend* X E_Modifier elsif (marker...pos).any? { |i| in_char_class?(codepoints[i], [:e_base, :e_base_gaz]) && codepoints[i + 1...pos].all? { |c| database.boundary[:extend] === c } } && database.boundary[:e_modifier] === current false # GB11. ZWJ X (Glue_After_Zwj | EBG) elsif database.boundary[:zwj] === previous && in_char_class?(current, [:glue_after_zwj, :e_base_gaz]) false # GB12. ^ (RI RI)* RI X RI # GB13. [^RI] (RI RI)* RI X RI elsif codepoints[marker..pos].all? { |c| database.boundary[:regional_indicator] === c } && codepoints[marker..pos].count { |c| database.boundary[:regional_indicator] === c }.even? false # GB999. Any ÷ Any else true end if should_break unpacked << codepoints[marker..pos - 1] marker = pos end end unpacked end # Reverse operation of unpack_graphemes. # # Unicode.pack_graphemes(Unicode.unpack_graphemes('क्षि')) # => 'क्षि' def pack_graphemes(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(type, codepoints) codepoints.inject([]) do |decomposed, cp| # if it's a hangul syllable starter character if HANGUL_SBASE <= cp && 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) && (!database.codepoints[cp].decomp_type || type == :compatibility) decomposed.concat decompose(type, ncp.dup) else decomposed << cp end end end # Compose decomposed characters to the composed form. def compose(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 && lindex < HANGUL_LCOUNT vindex = codepoints[starter_pos + 1] - HANGUL_VBASE rescue vindex = -1 if 0 <= vindex && vindex < HANGUL_VCOUNT tindex = codepoints[starter_pos + 2] - HANGUL_TBASE rescue tindex = -1 if 0 <= tindex && 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 # Rubinius' String#scrub, however, doesn't support ASCII-incompatible chars. if !defined?(Rubinius) # 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) return string if string.empty? return recode_windows1252_chars(string) if force string.scrub { |bad| recode_windows1252_chars(bad) } end else def tidy_bytes(string, force = false) return string if string.empty? return recode_windows1252_chars(string) if force # We can't transcode to the same format, so we choose a nearly-identical encoding. # We're going to 'transcode' bytes from UTF-8 when possible, then fall back to # CP1252 when we get errors. The final string will be 'converted' back to UTF-8 # before returning. reader = Encoding::Converter.new(Encoding::UTF_8, Encoding::UTF_16LE) source = string.dup out = "".force_encoding(Encoding::UTF_16LE) loop do reader.primitive_convert(source, out) _, _, _, error_bytes, _ = reader.primitive_errinfo break if error_bytes.nil? out << error_bytes.encode(Encoding::UTF_16LE, Encoding::Windows_1252, invalid: :replace, undef: :replace) end reader.finish out.encode!(Encoding::UTF_8) end 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::Unicode.default_normalization_form. def normalize(string, form = nil) form ||= @default_normalization_form # See http://www.unicode.org/reports/tr15, Table 1 codepoints = string.codepoints.to_a case form when :d reorder_characters(decompose(:canonical, codepoints)) when :c compose(reorder_characters(decompose(:canonical, codepoints))) when :kd reorder_characters(decompose(:compatibility, codepoints)) when :kc compose(reorder_characters(decompose(:compatibility, codepoints))) else raise ArgumentError, "#{form} is not a valid normalization variant", caller end.pack("U*".freeze) end def downcase(string) apply_mapping string, :lowercase_mapping end def upcase(string) apply_mapping string, :uppercase_mapping end def swapcase(string) apply_mapping string, :swapcase_mapping 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 # Initializing Codepoint object with default values def initialize @combining_class = 0 @uppercase_mapping = 0 @lowercase_mapping = 0 end def swapcase_mapping uppercase_mapping > 0 ? uppercase_mapping : lowercase_mapping end 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 => 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_key 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 apply_mapping(string, mapping) database.codepoints string.each_codepoint.map do |codepoint| cp = database.codepoints[codepoint] if cp && (ncp = cp.send(mapping)) && ncp > 0 ncp else codepoint end end.pack("U*") end def recode_windows1252_chars(string) string.encode(Encoding::UTF_8, Encoding::Windows_1252, invalid: :replace, undef: :replace) end def database @database ||= UnicodeDatabase.new end end end end