/
scanner.rl
908 lines (737 loc) · 27.8 KB
/
scanner.rl
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%%{
machine re_scanner;
include re_char_type "char_type.rl";
include re_property "property.rl";
dot = '.';
backslash = '\\';
alternation = '|';
beginning_of_line = '^';
end_of_line = '$';
range_open = '{';
range_close = '}';
curlies = range_open | range_close;
group_open = '(';
group_close = ')';
parantheses = group_open | group_close;
set_open = '[';
set_close = ']';
brackets = set_open | set_close;
comment = ('#' . [^\n]* . '\n'?);
class_name_posix = 'alnum' | 'alpha' | 'blank' |
'cntrl' | 'digit' | 'graph' |
'lower' | 'print' | 'punct' |
'space' | 'upper' | 'xdigit' |
'word' | 'ascii';
class_posix = ('[:' . '^'? . class_name_posix . ':]');
# these are not supported in ruby, and need verification
collating_sequence = '[.' . (alpha | [\-])+ . '.]';
character_equivalent = '[=' . alpha . '=]';
line_anchor = beginning_of_line | end_of_line;
anchor_char = [AbBzZG];
escaped_ascii = [abefnrtv];
octal_sequence = [0-7]{1,3};
hex_sequence = 'x' . xdigit{1,2};
hex_sequence_err = 'x' . [^0-9a-fA-F{];
codepoint_single = 'u' . xdigit{4};
codepoint_list = 'u{' . xdigit{1,6} . (space . xdigit{1,6})* . '}';
codepoint_sequence = codepoint_single | codepoint_list;
control_sequence = ('c' | 'C-') . (backslash . 'M-')? . backslash? . any;
meta_sequence = 'M-' . (backslash . ('c' | 'C-'))? . backslash? . any;
zero_or_one = '?' | '??' | '?+';
zero_or_more = '*' | '*?' | '*+';
one_or_more = '+' | '+?' | '++';
quantifier_greedy = '?' | '*' | '+';
quantifier_reluctant = '??' | '*?' | '+?';
quantifier_possessive = '?+' | '*+' | '++';
quantifier_mode = '?' | '+';
quantity_exact = (digit+);
quantity_minimum = (digit+) . ',';
quantity_maximum = ',' . (digit+);
quantity_range = (digit+) . ',' . (digit+);
quantifier_interval = range_open . ( quantity_exact | quantity_minimum |
quantity_maximum | quantity_range ) . range_close .
quantifier_mode?;
quantifiers = quantifier_greedy | quantifier_reluctant |
quantifier_possessive | quantifier_interval;
conditional = '(?(';
group_comment = '?#' . [^)]* . group_close;
group_atomic = '?>';
group_passive = '?:';
group_absence = '?~';
assertion_lookahead = '?=';
assertion_nlookahead = '?!';
assertion_lookbehind = '?<=';
assertion_nlookbehind = '?<!';
# try to treat every other group head as options group, like Ruby
group_options = '?' . ( [^!#'():<=>~]+ . ':'? ) ?;
group_ref = [gk];
group_name_char = (alnum | '_');
group_name_id = (group_name_char . (group_name_char+)?)?;
group_number = '-'? . [1-9] . ([0-9]+)?;
group_level = [+\-] . [0-9]+;
group_name = ('<' . group_name_id . '>') | ("'" . group_name_id . "'");
group_lookup = group_name | group_number;
group_named = ('?' . group_name );
group_name_ref = group_ref . (('<' . group_name_id . group_level? '>') |
("'" . group_name_id . group_level? "'"));
group_number_ref = group_ref . (('<' . group_number . group_level? '>') |
("'" . group_number . group_level? "'"));
group_type = group_atomic | group_passive | group_absence | group_named;
keep_mark = 'K';
assertion_type = assertion_lookahead | assertion_nlookahead |
assertion_lookbehind | assertion_nlookbehind;
# characters that 'break' a literal
meta_char = dot | backslash | alternation |
curlies | parantheses | brackets |
line_anchor | quantifier_greedy;
literal_delimiters = ']' | '}';
ascii_print = ((0x20..0x7e) - meta_char - '#');
ascii_nonprint = (0x01..0x1f | 0x7f);
utf8_2_byte = (0xc2..0xdf 0x80..0xbf);
utf8_3_byte = (0xe0..0xef 0x80..0xbf 0x80..0xbf);
utf8_4_byte = (0xf0..0xf4 0x80..0xbf 0x80..0xbf 0x80..0xbf);
non_literal_escape = char_type_char | anchor_char | escaped_ascii |
group_ref | keep_mark | [xucCM];
non_set_escape = (anchor_char - 'b') | group_ref | keep_mark |
multi_codepoint_char_type | [0-9cCM];
# EOF error, used where it can be detected
action premature_end_error {
text = ts ? copy(data, ts-1..-1) : data.pack('c*')
raise PrematureEndError.new( text )
}
# Invalid sequence error, used from sequences, like escapes and sets
action invalid_sequence_error {
text = ts ? copy(data, ts-1..-1) : data.pack('c*')
validation_error(:sequence, 'sequence', text)
}
# group (nesting) and set open/close actions
action group_opened { self.group_depth = group_depth + 1 }
action group_closed { self.group_depth = group_depth - 1 }
action set_opened { self.set_depth = set_depth + 1 }
action set_closed { self.set_depth = set_depth - 1 }
# Character set scanner, continues consuming characters until it meets the
# closing bracket of the set.
# --------------------------------------------------------------------------
character_set := |*
set_close > (set_meta, 2) @set_closed {
emit(:set, :close, *text(data, ts, te))
if in_set?
fret;
else
fgoto main;
end
};
'-]' @set_closed { # special case, emits two tokens
emit(:literal, :literal, copy(data, ts..te-2), ts, te - 1)
emit(:set, :close, copy(data, ts+1..te-1), ts + 1, te)
if in_set?
fret;
else
fgoto main;
end
};
'-&&' { # special case, emits two tokens
emit(:literal, :literal, '-', ts, te)
emit(:set, :intersection, '&&', ts, te)
};
'^' {
text = text(data, ts, te).first
if tokens.last[1] == :open
emit(:set, :negate, text, ts, te)
else
emit(:literal, :literal, text, ts, te)
end
};
'-' {
text = text(data, ts, te).first
# ranges cant start with a subset or intersection/negation/range operator
if tokens.last[0] == :set
emit(:literal, :literal, text, ts, te)
else
emit(:set, :range, text, ts, te)
end
};
# Unlike ranges, intersections can start or end at set boundaries, whereupon
# they match nothing: r = /[a&&]/; [r =~ ?a, r =~ ?&] # => [nil, nil]
'&&' {
emit(:set, :intersection, *text(data, ts, te))
};
backslash {
fcall set_escape_sequence;
};
set_open >(open_bracket, 1) >set_opened {
emit(:set, :open, *text(data, ts, te))
fcall character_set;
};
class_posix >(open_bracket, 1) @set_closed @eof(premature_end_error) {
text = text(data, ts, te).first
type = :posixclass
class_name = text[2..-3]
if class_name[0].chr == '^'
class_name = class_name[1..-1]
type = :nonposixclass
end
emit(type, class_name.to_sym, text, ts, te)
};
collating_sequence >(open_bracket, 1) @set_closed @eof(premature_end_error) {
emit(:set, :collation, *text(data, ts, te))
};
character_equivalent >(open_bracket, 1) @set_closed @eof(premature_end_error) {
emit(:set, :equivalent, *text(data, ts, te))
};
meta_char > (set_meta, 1) {
emit(:literal, :literal, *text(data, ts, te))
};
any |
ascii_nonprint |
utf8_2_byte |
utf8_3_byte |
utf8_4_byte {
char, *rest = *text(data, ts, te)
char.force_encoding('utf-8') if char.respond_to?(:force_encoding)
emit(:literal, :literal, char, *rest)
};
*|;
# set escapes scanner
# --------------------------------------------------------------------------
set_escape_sequence := |*
non_set_escape > (escaped_set_alpha, 2) {
emit(:escape, :literal, *text(data, ts, te, 1))
fret;
};
any > (escaped_set_alpha, 1) {
fhold;
fnext character_set;
fcall escape_sequence;
};
*|;
# escape sequence scanner
# --------------------------------------------------------------------------
escape_sequence := |*
[1-9] {
text = text(data, ts, te, 1).first
emit(:backref, :number, text, ts-1, te)
fret;
};
octal_sequence {
emit(:escape, :octal, *text(data, ts, te, 1))
fret;
};
meta_char {
case text = text(data, ts, te, 1).first
when '\.'; emit(:escape, :dot, text, ts-1, te)
when '\|'; emit(:escape, :alternation, text, ts-1, te)
when '\^'; emit(:escape, :bol, text, ts-1, te)
when '\$'; emit(:escape, :eol, text, ts-1, te)
when '\?'; emit(:escape, :zero_or_one, text, ts-1, te)
when '\*'; emit(:escape, :zero_or_more, text, ts-1, te)
when '\+'; emit(:escape, :one_or_more, text, ts-1, te)
when '\('; emit(:escape, :group_open, text, ts-1, te)
when '\)'; emit(:escape, :group_close, text, ts-1, te)
when '\{'; emit(:escape, :interval_open, text, ts-1, te)
when '\}'; emit(:escape, :interval_close, text, ts-1, te)
when '\['; emit(:escape, :set_open, text, ts-1, te)
when '\]'; emit(:escape, :set_close, text, ts-1, te)
when "\\\\";
emit(:escape, :backslash, text, ts-1, te)
end
fret;
};
escaped_ascii > (escaped_alpha, 7) {
# \b is emitted as backspace only when inside a character set, otherwise
# it is a word boundary anchor. A syntax might "normalize" it if needed.
case text = text(data, ts, te, 1).first
when '\a'; emit(:escape, :bell, text, ts-1, te)
when '\b'; emit(:escape, :backspace, text, ts-1, te)
when '\e'; emit(:escape, :escape, text, ts-1, te)
when '\f'; emit(:escape, :form_feed, text, ts-1, te)
when '\n'; emit(:escape, :newline, text, ts-1, te)
when '\r'; emit(:escape, :carriage, text, ts-1, te)
when '\t'; emit(:escape, :tab, text, ts-1, te)
when '\v'; emit(:escape, :vertical_tab, text, ts-1, te)
end
fret;
};
codepoint_sequence > (escaped_alpha, 6) $eof(premature_end_error) {
text = text(data, ts, te, 1).first
if text[2].chr == '{'
emit(:escape, :codepoint_list, text, ts-1, te)
else
emit(:escape, :codepoint, text, ts-1, te)
end
fret;
};
hex_sequence > (escaped_alpha, 5) $eof(premature_end_error) {
emit(:escape, :hex, *text(data, ts, te, 1))
fret;
};
hex_sequence_err @invalid_sequence_error {
fret;
};
control_sequence >(escaped_alpha, 4) $eof(premature_end_error) {
emit_meta_control_sequence(data, ts, te, :control)
fret;
};
meta_sequence >(backslashed, 3) $eof(premature_end_error) {
emit_meta_control_sequence(data, ts, te, :meta_sequence)
fret;
};
char_type_char > (escaped_alpha, 2) {
fhold;
fnext *(in_set? ? fentry(character_set) : fentry(main));
fcall char_type;
};
property_char > (escaped_alpha, 2) {
fhold;
fnext *(in_set? ? fentry(character_set) : fentry(main));
fcall unicode_property;
};
(any -- non_literal_escape) > (escaped_alpha, 1) {
emit(:escape, :literal, *text(data, ts, te, 1))
fret;
};
*|;
# conditional expressions scanner
# --------------------------------------------------------------------------
conditional_expression := |*
group_lookup . ')' {
text = text(data, ts, te-1).first
emit(:conditional, :condition, text, ts, te-1)
emit(:conditional, :condition_close, ')', te-1, te)
};
any {
fhold;
fcall main;
};
*|;
# Main scanner
# --------------------------------------------------------------------------
main := |*
# Meta characters
# ------------------------------------------------------------------------
dot {
emit(:meta, :dot, *text(data, ts, te))
};
alternation {
if conditional_stack.last == group_depth
emit(:conditional, :separator, *text(data, ts, te))
else
emit(:meta, :alternation, *text(data, ts, te))
end
};
# Anchors
# ------------------------------------------------------------------------
beginning_of_line {
emit(:anchor, :bol, *text(data, ts, te))
};
end_of_line {
emit(:anchor, :eol, *text(data, ts, te))
};
backslash . keep_mark > (backslashed, 4) {
emit(:keep, :mark, *text(data, ts, te))
};
backslash . anchor_char > (backslashed, 3) {
case text = text(data, ts, te).first
when '\\A'; emit(:anchor, :bos, text, ts, te)
when '\\z'; emit(:anchor, :eos, text, ts, te)
when '\\Z'; emit(:anchor, :eos_ob_eol, text, ts, te)
when '\\b'; emit(:anchor, :word_boundary, text, ts, te)
when '\\B'; emit(:anchor, :nonword_boundary, text, ts, te)
when '\\G'; emit(:anchor, :match_start, text, ts, te)
end
};
literal_delimiters {
append_literal(data, ts, te)
};
# Character sets
# ------------------------------------------------------------------------
set_open >set_opened {
emit(:set, :open, *text(data, ts, te))
fcall character_set;
};
# Conditional expression
# (?(condition)Y|N) conditional expression
# ------------------------------------------------------------------------
conditional {
text = text(data, ts, te).first
conditional_stack << group_depth
emit(:conditional, :open, text[0..-2], ts, te-1)
emit(:conditional, :condition_open, '(', te-1, te)
fcall conditional_expression;
};
# (?#...) comments: parsed as a single expression, without introducing a
# new nesting level. Comments may not include parentheses, escaped or not.
# special case for close, action performed on all transitions to get the
# correct closing count.
# ------------------------------------------------------------------------
group_open . group_comment $group_closed {
emit(:group, :comment, *text(data, ts, te))
};
# Expression options:
# (?imxdau-imx) option on/off
# i: ignore case
# m: multi-line (dot(.) match newline)
# x: extended form
# d: default class rules (1.9 compatible)
# a: ASCII class rules (\s, \w, etc.)
# u: Unicode class rules (\s, \w, etc.)
#
# (?imxdau-imx:subexp) option on/off for subexp
# ------------------------------------------------------------------------
group_open . group_options >group_opened {
text = text(data, ts, te).first
if text[2..-1] =~ /([^\-mixdau:]|^$)|-.*([dau])/
raise InvalidGroupOption.new($1 || "-#{$2}", text)
end
emit_options(text, ts, te)
};
# Assertions
# (?=subexp) look-ahead
# (?!subexp) negative look-ahead
# (?<=subexp) look-behind
# (?<!subexp) negative look-behind
# ------------------------------------------------------------------------
group_open . assertion_type >group_opened {
case text = text(data, ts, te).first
when '(?='; emit(:assertion, :lookahead, text, ts, te)
when '(?!'; emit(:assertion, :nlookahead, text, ts, te)
when '(?<='; emit(:assertion, :lookbehind, text, ts, te)
when '(?<!'; emit(:assertion, :nlookbehind, text, ts, te)
end
};
# Groups
# (?:subexp) passive (non-captured) group
# (?>subexp) atomic group, don't backtrack in subexp.
# (?~subexp) absence group, matches anything that is not subexp
# (?<name>subexp) named group
# (?'name'subexp) named group (single quoted version)
# (subexp) captured group
# ------------------------------------------------------------------------
group_open . group_type >group_opened {
case text = text(data, ts, te).first
when '(?:'; emit(:group, :passive, text, ts, te)
when '(?>'; emit(:group, :atomic, text, ts, te)
when '(?~'; emit(:group, :absence, text, ts, te)
when /^\(\?(?:<>|'')/
validation_error(:group, 'named group', 'name is empty')
when /^\(\?<\w*>/
emit(:group, :named_ab, text, ts, te)
when /^\(\?'\w*'/
emit(:group, :named_sq, text, ts, te)
end
};
group_open @group_opened {
text = text(data, ts, te).first
emit(:group, :capture, text, ts, te)
};
group_close @group_closed {
if conditional_stack.last == group_depth + 1
conditional_stack.pop
emit(:conditional, :close, *text(data, ts, te))
else
if spacing_stack.length > 1 &&
spacing_stack.last[:depth] == group_depth + 1
spacing_stack.pop
self.free_spacing = spacing_stack.last[:free_spacing]
end
emit(:group, :close, *text(data, ts, te))
end
};
# Group backreference, named and numbered
# ------------------------------------------------------------------------
backslash . (group_name_ref | group_number_ref) > (backslashed, 4) {
case text = text(data, ts, te).first
when /^\\([gk])(<>|'')/ # angle brackets
validation_error(:backref, 'ref/call', 'ref ID is empty')
when /^\\([gk])<[^\d+-]\w*>/ # angle-brackets
if $1 == 'k'
emit(:backref, :name_ref_ab, text, ts, te)
else
emit(:backref, :name_call_ab, text, ts, te)
end
when /^\\([gk])'[^\d+-]\w*'/ #single quotes
if $1 == 'k'
emit(:backref, :name_ref_sq, text, ts, te)
else
emit(:backref, :name_call_sq, text, ts, te)
end
when /^\\([gk])<\d+>/ # angle-brackets
if $1 == 'k'
emit(:backref, :number_ref_ab, text, ts, te)
else
emit(:backref, :number_call_ab, text, ts, te)
end
when /^\\([gk])'\d+'/ # single quotes
if $1 == 'k'
emit(:backref, :number_ref_sq, text, ts, te)
else
emit(:backref, :number_call_sq, text, ts, te)
end
when /^\\(?:g<\+|g<-|(k)<-)\d+>/ # angle-brackets
if $1 == 'k'
emit(:backref, :number_rel_ref_ab, text, ts, te)
else
emit(:backref, :number_rel_call_ab, text, ts, te)
end
when /^\\(?:g'\+|g'-|(k)'-)\d+'/ # single quotes
if $1 == 'k'
emit(:backref, :number_rel_ref_sq, text, ts, te)
else
emit(:backref, :number_rel_call_sq, text, ts, te)
end
when /^\\k<[^\d+\-]\w*[+\-]\d+>/ # angle-brackets
emit(:backref, :name_recursion_ref_ab, text, ts, te)
when /^\\k'[^\d+\-]\w*[+\-]\d+'/ # single-quotes
emit(:backref, :name_recursion_ref_sq, text, ts, te)
when /^\\([gk])<[+\-]?\d+[+\-]\d+>/ # angle-brackets
emit(:backref, :number_recursion_ref_ab, text, ts, te)
when /^\\([gk])'[+\-]?\d+[+\-]\d+'/ # single-quotes
emit(:backref, :number_recursion_ref_sq, text, ts, te)
end
};
# Quantifiers
# ------------------------------------------------------------------------
zero_or_one {
case text = text(data, ts, te).first
when '?' ; emit(:quantifier, :zero_or_one, text, ts, te)
when '??'; emit(:quantifier, :zero_or_one_reluctant, text, ts, te)
when '?+'; emit(:quantifier, :zero_or_one_possessive, text, ts, te)
end
};
zero_or_more {
case text = text(data, ts, te).first
when '*' ; emit(:quantifier, :zero_or_more, text, ts, te)
when '*?'; emit(:quantifier, :zero_or_more_reluctant, text, ts, te)
when '*+'; emit(:quantifier, :zero_or_more_possessive, text, ts, te)
end
};
one_or_more {
case text = text(data, ts, te).first
when '+' ; emit(:quantifier, :one_or_more, text, ts, te)
when '+?'; emit(:quantifier, :one_or_more_reluctant, text, ts, te)
when '++'; emit(:quantifier, :one_or_more_possessive, text, ts, te)
end
};
quantifier_interval {
emit(:quantifier, :interval, *text(data, ts, te))
};
# Catch unmatched curly braces as literals
range_open {
append_literal(data, ts, te)
};
# Escaped sequences
# ------------------------------------------------------------------------
backslash > (backslashed, 1) {
fcall escape_sequence;
};
comment {
if free_spacing
emit(:free_space, :comment, *text(data, ts, te))
else
append_literal(data, ts, te)
end
};
space+ {
if free_spacing
emit(:free_space, :whitespace, *text(data, ts, te))
else
append_literal(data, ts, te)
end
};
# Literal: any run of ASCII (pritable or non-printable), and/or UTF-8,
# except meta characters.
# ------------------------------------------------------------------------
(ascii_print -- space)+ |
ascii_nonprint+ |
utf8_2_byte+ |
utf8_3_byte+ |
utf8_4_byte+ {
append_literal(data, ts, te)
};
*|;
}%%
# THIS IS A GENERATED FILE, DO NOT EDIT DIRECTLY
# This file was generated from lib/regexp_parser/scanner/scanner.rl
class Regexp::Scanner
# General scanner error (catch all)
class ScannerError < StandardError; end
# Base for all scanner validation errors
class ValidationError < StandardError
def initialize(reason)
super reason
end
end
# Unexpected end of pattern
class PrematureEndError < ScannerError
def initialize(where = '')
super "Premature end of pattern at #{where}"
end
end
# Invalid sequence format. Used for escape sequences, mainly.
class InvalidSequenceError < ValidationError
def initialize(what = 'sequence', where = '')
super "Invalid #{what} at #{where}"
end
end
# Invalid group. Used for named groups.
class InvalidGroupError < ValidationError
def initialize(what, reason)
super "Invalid #{what}, #{reason}."
end
end
# Invalid groupOption. Used for inline options.
class InvalidGroupOption < ValidationError
def initialize(option, text)
super "Invalid group option #{option} in #{text}"
end
end
# Invalid back reference. Used for name a number refs/calls.
class InvalidBackrefError < ValidationError
def initialize(what, reason)
super "Invalid back reference #{what}, #{reason}"
end
end
# The property name was not recognized by the scanner.
class UnknownUnicodePropertyError < ValidationError
def initialize(name)
super "Unknown unicode character property name #{name}"
end
end
# Scans the given regular expression text, or Regexp object and collects the
# emitted token into an array that gets returned at the end. If a block is
# given, it gets called for each emitted token.
#
# This method may raise errors if a syntax error is encountered.
# --------------------------------------------------------------------------
def self.scan(input_object, &block)
new.scan(input_object, &block)
end
def scan(input_object, &block)
self.literal = nil
stack = []
if input_object.is_a?(Regexp)
input = input_object.source
self.free_spacing = (input_object.options & Regexp::EXTENDED != 0)
else
input = input_object
self.free_spacing = false
end
self.spacing_stack = [{:free_spacing => free_spacing, :depth => 0}]
data = input.unpack("c*") if input.is_a?(String)
eof = data.length
self.tokens = []
self.block = block_given? ? block : nil
self.set_depth = 0
self.group_depth = 0
self.conditional_stack = []
%% write data;
%% write init;
%% write exec;
# to avoid "warning: assigned but unused variable - testEof"
testEof = testEof
if cs == re_scanner_error
text = ts ? copy(data, ts-1..-1) : data.pack('c*')
raise ScannerError.new("Scan error at '#{text}'")
end
raise PrematureEndError.new("(missing group closing paranthesis) "+
"[#{group_depth}]") if in_group?
raise PrematureEndError.new("(missing set closing bracket) "+
"[#{set_depth}]") if in_set?
# when the entire expression is a literal run
emit_literal if literal
tokens
end
# lazy-load property maps when first needed
require 'yaml'
PROP_MAPS_DIR = File.expand_path('../scanner/properties', __FILE__)
def self.short_prop_map
@short_prop_map ||= YAML.load_file("#{PROP_MAPS_DIR}/short.yml")
end
def self.long_prop_map
@long_prop_map ||= YAML.load_file("#{PROP_MAPS_DIR}/long.yml")
end
# Emits an array with the details of the scanned pattern
def emit(type, token, text, ts, te)
#puts "EMIT: type: #{type}, token: #{token}, text: #{text}, ts: #{ts}, te: #{te}"
emit_literal if literal
if block
block.call type, token, text, ts, te
end
tokens << [type, token, text, ts, te]
end
private
attr_accessor :tokens, :literal, :block, :free_spacing, :spacing_stack,
:group_depth, :set_depth, :conditional_stack
def in_group?
group_depth > 0
end
def in_set?
set_depth > 0
end
# Copy from ts to te from data as text
def copy(data, range)
data[range].pack('c*')
end
# Copy from ts to te from data as text, returning an array with the text
# and the offsets used to copy it.
def text(data, ts, te, soff = 0)
[copy(data, ts-soff..te-1), ts-soff, te]
end
# Appends one or more characters to the literal buffer, to be emitted later
# by a call to emit_literal. Contents can be a mix of ASCII and UTF-8.
def append_literal(data, ts, te)
self.literal = literal || []
literal << text(data, ts, te)
end
# Emits the literal run collected by calls to the append_literal method,
# using the total start (ts) and end (te) offsets of the run.
def emit_literal
ts, te = literal.first[1], literal.last[2]
text = literal.map {|t| t[0]}.join
text.force_encoding('utf-8') if text.respond_to?(:force_encoding)
self.literal = nil
emit(:literal, :literal, text, ts, te)
end
def emit_options(text, ts, te)
token = nil
# Ruby allows things like '(?-xxxx)' or '(?xx-xx--xx-:abc)'.
text =~ /\(\?([mixdau]*)(-(?:[mix]*))*(:)?/
positive, negative, group_local = $1, $2, $3
if positive.include?('x')
self.free_spacing = true
end
# If the x appears in both, treat it like ruby does, the second cancels
# the first.
if negative && negative.include?('x')
self.free_spacing = false
end
if group_local
spacing_stack << {:free_spacing => free_spacing, :depth => group_depth}
token = :options
else
# switch for parent group level
spacing_stack.last[:free_spacing] = free_spacing
token = :options_switch
end
emit(:group, token, text, ts, te)
end
def emit_meta_control_sequence(data, ts, te, token)
if data.last < 0x00 || data.last > 0x7F
validation_error(:sequence, 'escape', token.to_s)
end
emit(:escape, token, *text(data, ts, te, 1))
end
# Centralizes and unifies the handling of validation related
# errors.
def validation_error(type, what, reason)
case type
when :group
error = InvalidGroupError.new(what, reason)
when :backref
error = InvalidBackrefError.new(what, reason)
when :sequence
error = InvalidSequenceError.new(what, reason)
end
raise error # unless @@config.validation_ignore
end
end # module Regexp::Scanner