Contents

require 'diff/lcs'

module RSpec
  module Matchers
    class FileMatcher < Matcher
      def initialize expected
        super(:have_different_contents, expected) do |*_expected|
          match_for_should do |actual|
            perform_match(actual, _expected[0])
          end

          match_for_should_not do |actual|
            !perform_match(actual, _expected[0])
          end

          def perform_match(actual, expected)
            expected = File.open(expected).read if expected.is_a?(Pathname)
            expected = expected.scan(/[^\n]+/) unless expected.is_a?(Array)

            actual = File.open(actual).read if actual.is_a?(Pathname)
            actual = actual.scan(/[^\n]+/) unless actual.is_a?(Array)

            differences = Diff::LCS::diff(expected, actual)
            @diff = differences.map do |chunk|
                added_at = (add = chunk.detect{|d| d.action == '+'}) && add.position+1
                removed_at = (remove = chunk.detect{|d| d.action == '-'}) && remove.position+1
                "Line #{added_at}/#{removed_at}:\n"+
                chunk.map do |change|
                  "#{change.action} #{change.element}"
                end*"\n"
              end*"\n"
            @diff != ''
          end

          def failure_message_for_should
            "expected a difference, but got none"
          end

          failure_message_for_should_not do |actual|
            "expected no difference, but got:\n#{@diff}"
          end
        end
      end
    end

    def have_different_contents(expected)
      FileMatcher.new(expected)
    end
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
activefacts-0.8.10	spec/helpers/file_matcher.rb