lexers/gherkin.lua

   1 -- Copyright 2015-2016 Jason Schindler. See LICENSE.
   2 -- Gherkin (https://github.com/cucumber/cucumber/wiki/Gherkin) LPeg lexer.
   3
   4 local l = require('lexer')
   5 local token, word_match = l.token, l.word_match
   6 local P, R, S = lpeg.P, lpeg.R, lpeg.S
   7
   8 local M = {_NAME = 'gherkin'}
   9
  10 -- Whitespace.
  11 local ws = token(l.WHITESPACE, l.space^1)
  12
  13 -- Tags.
  14 local tag = token('tag', '@' * l.word^0)
  15
  16 -- Comments.
  17 local comment = token(l.COMMENT, '#' * l.nonnewline^0)
  18
  19 -- Strings.
  20 local doc_str = '"""' * (l.any - '"""')^0 * P('"""')^-1
  21 local dq_str = l.delimited_range('"')
  22
  23 local string = token(l.STRING, doc_str + dq_str)
  24
  25 -- Placeholders.
  26 local placeholder = token('placeholder', l.nested_pair('<', '>'))
  27
  28 -- Keywords.
  29 local keyword = token(l.KEYWORD, word_match{
  30   'Given', 'When', 'Then', 'And', 'But'
  31 })
  32
  33 -- Identifiers.
  34 local identifier = token(l.KEYWORD, P('Scenario Outline') + word_match{
  35   'Feature', 'Background', 'Scenario', 'Scenarios', 'Examples'
  36 })
  37
  38 -- Examples.
  39 local example = token('example', '|' * l.nonnewline^0)
  40
  41 -- Numbers.
  42 local number = token(l.NUMBER, l.float + l.integer)
  43
  44 M._rules = {
  45   {'whitespace', ws},
  46   {'comment', comment},
  47   {'tag', tag},
  48   {'placeholder', placeholder},
  49   {'keyword', keyword},
  50   {'identifier', identifier},
  51   {'example', example},
  52   {'string', string},
  53   {'number', number}
  54 }
  55
  56 M._tokenstyles = {
  57   tag = l.STYLE_LABEL,
  58   placeholder = l.STYLE_NUMBER,
  59   example = l.STYLE_NUMBER
  60 }
  61
  62 M._FOLDBYINDENTATION = true
  63
  64 return M