Create a Relish .nav file from a directory of *.feature files

generate_relish_nav.rb

require 'gherkin/parser'
require 'gherkin/pickles/compiler'

module RelishNav
  class Collector
    def initialize(feature_dir)
      @feature_dir = feature_dir
      @parser = Gherkin::Parser.new
    end

    def collect_features(initial_entries = {})
      dirs = initial_entries
      Dir["#{feature_dir}/**/*.feature"].each do |file|
        dir = relative(File.dirname(file), feature_dir)

        (dirs[dir] ||= []).tap do |nodes|
          node = extract_gherkin_info(file)

          feature_file = relative(file, "#{feature_dir}/#{dir}")
          node = node.merge(file: feature_file)
          nodes << node
        end
      end
      dirs
    end

    private

    attr_reader :parser
    attr_reader :feature_dir

    def relative(path, base_dir)
      path = path.sub("#{base_dir}", '')
      path = path[1..-1] if path.start_with?('/')
      path
    end

    def extract_gherkin_info(file)
      document = parser.parse(IO.read(file))
      feature = document.fetch(:feature)
      name = feature.fetch(:name)
      tags = feature.fetch(:tags).map { |taginfo| taginfo[:name]}

      # NOTE: neither name nor tags are used yet
      { name: name, tags: tags }
    end
  end

  class Generator
    def generate(data, output_file)
      dirs = data

      File.open(output_file, "w") do |file|
        dirs.each_pair do |dir, nodes|
          if dir.empty?
            dump_nodes(file, nodes, level: 0)
          else
            file.puts "- #{dir}:"
            dump_nodes(file, nodes, level: 1)
          end
        end
      end
    end

    def dump_nodes(file, nodes, options)
      indent = '  ' * options.fetch(:level)
      nodes.each do |node|
        file.puts "#{indent}- #{node.fetch(:file)}"
      end
    end
  end
end


initial_entries = {
  '' => [
    { name: '', file: "Changelog.md", tags: [] },
    { name: '', file: "Autotest.md", tags: [] }
  ]
}

feature_dir = '/home/me/github.com/rspec-core/features'
output_file = ".nav.new"
collector = RelishNav::Collector.new(feature_dir)
data = collector.collect_features(initial_entries)

generator = RelishNav::Generator.new
generator.generate(data, output_file)