aboutsummaryrefslogtreecommitdiffstats
path: root/actionpack/lib/action_dispatch/journey/scanner.rb
blob: 19e0bc03d61198ebe7dee362bdb4c11b9bf2aceb (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
require 'strscan'

module ActionDispatch
  module Journey # :nodoc:
    class Scanner # :nodoc:
      def initialize
        @ss = nil
      end

      def scan_setup(str)
        @ss = StringScanner.new(str)
      end

      def eos?
        @ss.eos?
      end

      def pos
        @ss.pos
      end

      def pre_match
        @ss.pre_match
      end

      def next_token
        return if @ss.eos?

        until token = scan || @ss.eos?; end
        token
      end

      private

        def scan
          case
            # /
          when text = @ss.scan(/\//)
            [:SLASH, text]
          when text = @ss.scan(/\*\w+/)
            [:STAR, text]
          when text = @ss.scan(/(?<!\\)\(/)
            [:LPAREN, text]
          when text = @ss.scan(/(?<!\\)\)/)
            [:RPAREN, text]
          when text = @ss.scan(/\|/)
            [:OR, text]
          when text = @ss.scan(/\./)
            [:DOT, text]
          when text = @ss.scan(/(?<!\\):\w+/)
            [:SYMBOL, text]
          when text = @ss.scan(/(?:[\w%\-~!$&'*+,;=@]|\\:|\\\(|\\\))+/)
            [:LITERAL, text.tr('\\', '')]
            # any char
          when text = @ss.scan(/./)
            [:LITERAL, text]
          end
        end
    end
  end
end