Current File : //opt/alt/ruby31/share/ruby/ripper/lexer.rb
# frozen_string_literal: true
#
# $Id$
#
# Copyright (c) 2004,2005 Minero Aoki
#
# This program is free software.
# You can distribute and/or modify this program under the Ruby License.
# For details of Ruby License, see ruby/COPYING.
#
require 'ripper/core'
class Ripper
# Tokenizes the Ruby program and returns an array of strings.
# The +filename+ and +lineno+ arguments are mostly ignored, since the
# return value is just the tokenized input.
# By default, this method does not handle syntax errors in +src+,
# use the +raise_errors+ keyword to raise a SyntaxError for an error in +src+.
#
# p Ripper.tokenize("def m(a) nil end")
# # => ["def", " ", "m", "(", "a", ")", " ", "nil", " ", "end"]
#
def Ripper.tokenize(src, filename = '-', lineno = 1, **kw)
Lexer.new(src, filename, lineno).tokenize(**kw)
end
# Tokenizes the Ruby program and returns an array of an array,
# which is formatted like
# <code>[[lineno, column], type, token, state]</code>.
# The +filename+ argument is mostly ignored.
# By default, this method does not handle syntax errors in +src+,
# use the +raise_errors+ keyword to raise a SyntaxError for an error in +src+.
#
# require 'ripper'
# require 'pp'
#
# pp Ripper.lex("def m(a) nil end")
# #=> [[[1, 0], :on_kw, "def", FNAME ],
# [[1, 3], :on_sp, " ", FNAME ],
# [[1, 4], :on_ident, "m", ENDFN ],
# [[1, 5], :on_lparen, "(", BEG|LABEL],
# [[1, 6], :on_ident, "a", ARG ],
# [[1, 7], :on_rparen, ")", ENDFN ],
# [[1, 8], :on_sp, " ", BEG ],
# [[1, 9], :on_kw, "nil", END ],
# [[1, 12], :on_sp, " ", END ],
# [[1, 13], :on_kw, "end", END ]]
#
def Ripper.lex(src, filename = '-', lineno = 1, **kw)
Lexer.new(src, filename, lineno).lex(**kw)
end
class Lexer < ::Ripper #:nodoc: internal use only
class State
attr_reader :to_int, :to_s
def initialize(i)
@to_int = i
@to_s = Ripper.lex_state_name(i)
freeze
end
def [](index)
case index
when 0, :to_int
@to_int
when 1, :to_s
@event
else
nil
end
end
alias to_i to_int
alias inspect to_s
def pretty_print(q) q.text(to_s) end
def ==(i) super or to_int == i end
def &(i) self.class.new(to_int & i) end
def |(i) self.class.new(to_int | i) end
def allbits?(i) to_int.allbits?(i) end
def anybits?(i) to_int.anybits?(i) end
def nobits?(i) to_int.nobits?(i) end
end
class Elem
attr_accessor :pos, :event, :tok, :state, :message
def initialize(pos, event, tok, state, message = nil)
@pos = pos
@event = event
@tok = tok
@state = State.new(state)
@message = message
end
def [](index)
case index
when 0, :pos
@pos
when 1, :event
@event
when 2, :tok
@tok
when 3, :state
@state
when 4, :message
@message
else
nil
end
end
def inspect
"#<#{self.class}: #{event}@#{pos[0]}:#{pos[1]}:#{state}: #{tok.inspect}#{": " if message}#{message}>"
end
alias to_s inspect
def pretty_print(q)
q.group(2, "#<#{self.class}:", ">") {
q.breakable
q.text("#{event}@#{pos[0]}:#{pos[1]}")
q.breakable
state.pretty_print(q)
q.breakable
q.text("token: ")
tok.pretty_print(q)
if message
q.breakable
q.text("message: ")
q.text(message)
end
}
end
def to_a
if @message
[@pos, @event, @tok, @state, @message]
else
[@pos, @event, @tok, @state]
end
end
end
attr_reader :errors
def tokenize(**kw)
parse(**kw).sort_by(&:pos).map(&:tok)
end
def lex(**kw)
parse(**kw).sort_by(&:pos).map(&:to_a)
end
# parse the code and returns elements including errors.
def scan(**kw)
result = (parse(**kw) + errors + @stack.flatten).uniq.sort_by {|e| [*e.pos, (e.message ? -1 : 0)]}
result.each_with_index do |e, i|
if e.event == :on_parse_error and e.tok.empty? and (pre = result[i-1]) and
pre.pos[0] == e.pos[0] and (pre.pos[1] + pre.tok.size) == e.pos[1]
e.tok = pre.tok
e.pos[1] = pre.pos[1]
result[i-1] = e
result[i] = pre
end
end
result
end
def parse(raise_errors: false)
@errors = []
@buf = []
@stack = []
super()
@buf = @stack.pop unless @stack.empty?
if raise_errors and !@errors.empty?
raise SyntaxError, @errors.map(&:message).join(' ;')
end
@buf.flatten!
unless (result = @buf).empty?
result.concat(@buf) until (@buf = []; super(); @buf.flatten!; @buf.empty?)
end
result
end
private
unless SCANNER_EVENT_TABLE.key?(:ignored_sp)
SCANNER_EVENT_TABLE[:ignored_sp] = 1
SCANNER_EVENTS << :ignored_sp
EVENTS << :ignored_sp
end
def on_heredoc_dedent(v, w)
ignored_sp = []
heredoc = @buf.last
if Array === heredoc
heredoc.each_with_index do |e, i|
if Elem === e and e.event == :on_tstring_content and e.pos[1].zero?
tok = e.tok.dup if w > 0 and /\A\s/ =~ e.tok
if (n = dedent_string(e.tok, w)) > 0
if e.tok.empty?
e.tok = tok[0, n]
e.event = :on_ignored_sp
next
end
ignored_sp << [i, Elem.new(e.pos.dup, :on_ignored_sp, tok[0, n], e.state)]
e.pos[1] += n
end
end
end
end
ignored_sp.reverse_each do |i, e|
heredoc[i, 0] = [e]
end
v
end
def on_heredoc_beg(tok)
@stack.push @buf
buf = []
@buf.push buf
@buf = buf
@buf.push Elem.new([lineno(), column()], __callee__, tok, state())
end
def on_heredoc_end(tok)
@buf.push Elem.new([lineno(), column()], __callee__, tok, state())
@buf = @stack.pop
end
def _push_token(tok)
e = Elem.new([lineno(), column()], __callee__, tok, state())
@buf.push(e)
e
end
def on_error1(mesg)
@errors.push Elem.new([lineno(), column()], __callee__, token(), state(), mesg)
end
def on_error2(mesg, elem)
@errors.push Elem.new(elem.pos, __callee__, elem.tok, elem.state, mesg)
end
PARSER_EVENTS.grep(/_error\z/) do |e|
arity = PARSER_EVENT_TABLE.fetch(e)
alias_method "on_#{e}", "on_error#{arity}"
end
alias compile_error on_error1
(SCANNER_EVENTS.map {|event|:"on_#{event}"} - private_instance_methods(false)).each do |event|
alias_method event, :_push_token
end
end
# [EXPERIMENTAL]
# Parses +src+ and return a string which was matched to +pattern+.
# +pattern+ should be described as Regexp.
#
# require 'ripper'
#
# p Ripper.slice('def m(a) nil end', 'ident') #=> "m"
# p Ripper.slice('def m(a) nil end', '[ident lparen rparen]+') #=> "m(a)"
# p Ripper.slice("<<EOS\nstring\nEOS",
# 'heredoc_beg nl $(tstring_content*) heredoc_end', 1)
# #=> "string\n"
#
def Ripper.slice(src, pattern, n = 0)
if m = token_match(src, pattern)
then m.string(n)
else nil
end
end
def Ripper.token_match(src, pattern) #:nodoc:
TokenPattern.compile(pattern).match(src)
end
class TokenPattern #:nodoc:
class Error < ::StandardError # :nodoc:
end
class CompileError < Error # :nodoc:
end
class MatchError < Error # :nodoc:
end
class << self
alias compile new
end
def initialize(pattern)
@source = pattern
@re = compile(pattern)
end
def match(str)
match_list(::Ripper.lex(str))
end
def match_list(tokens)
if m = @re.match(map_tokens(tokens))
then MatchData.new(tokens, m)
else nil
end
end
private
def compile(pattern)
if m = /[^\w\s$()\[\]{}?*+\.]/.match(pattern)
raise CompileError, "invalid char in pattern: #{m[0].inspect}"
end
buf = +''
pattern.scan(/(?:\w+|\$\(|[()\[\]\{\}?*+\.]+)/) do |tok|
case tok
when /\w/
buf.concat map_token(tok)
when '$('
buf.concat '('
when '('
buf.concat '(?:'
when /[?*\[\])\.]/
buf.concat tok
else
raise 'must not happen'
end
end
Regexp.compile(buf)
rescue RegexpError => err
raise CompileError, err.message
end
def map_tokens(tokens)
tokens.map {|pos,type,str| map_token(type.to_s.delete_prefix('on_')) }.join
end
MAP = {}
seed = ('a'..'z').to_a + ('A'..'Z').to_a + ('0'..'9').to_a
SCANNER_EVENT_TABLE.each do |ev, |
raise CompileError, "[RIPPER FATAL] too many system token" if seed.empty?
MAP[ev.to_s.delete_prefix('on_')] = seed.shift
end
def map_token(tok)
MAP[tok] or raise CompileError, "unknown token: #{tok}"
end
class MatchData # :nodoc:
def initialize(tokens, match)
@tokens = tokens
@match = match
end
def string(n = 0)
return nil unless @match
match(n).join
end
private
def match(n = 0)
return [] unless @match
@tokens[@match.begin(n)...@match.end(n)].map {|pos,type,str| str }
end
end
end
end