simple_js_gherkin.js

// This is how I would love to use it from Javascript...

var gherkin = require('gherkin');

var simpleListener = {
  feature: function(keyword, name, description, line) {};
  scenario: function(keyword, name, description, line) {};
  step: function(keyword, name, line) {};
};

var lexer = gherkin.lexer.en(simpleListener);

lexer.scan(source);

simple_ruby_gherkin.rb

require 'rubygems'
require 'gherkin/rb_lexer/en'

# Implements a subset of the listener interface needed for the
# simple feature below. With more complex features we'll need to
# implement more methods. The full interface is best described in
# Java: http://github.com/aslakhellesoy/gherkin/blob/master/java/src/main/java/gherkin/lexer/Listener.java
class SimpleListener
  def feature(keyword, name, description, line)
    puts "#{keyword}: #{name}"
    puts "  #{description}"
    puts
  end

  def scenario(keyword, name, description, line)
    puts "  #{keyword}: #{name}"
  end

  def step(keyword, name, line)
    puts "    #{keyword}#{name}"
  end

  def eof
  end
end

lexer = Gherkin::RbLexer::En.new(SimpleListener.new)

feature = <<-EOF
Feature: Do some simple scanning
  Because we want to use Javascript
  
  Scenario: Hello World
    Given I have some Doppio
    And I convert the English Ruby Gherkin Lexer to Javascript
    Then I should be able to lex a .feature file with Node.js
EOF

lexer.scan(feature)