jekyll-build-pages/bin/compare_expected_output

#! /usr/bin/env ruby

require "pathname"
require "shellwords"

project_path = ARGV[0]

Dir.chdir(project_path)

expected_files = Dir["_expected/**/*"].select { |path| File.file?(path) }.map { |path| Pathname.new(path).relative_path_from("_expected").to_s }
actual_files = Dir["_site/**/*"].select { |path| File.file?(path) }.map { |path| Pathname.new(path).relative_path_from("_site").to_s }

differences = []

expected_files.each do |expected_file|
  if actual_files.include?(expected_file)
    diff = `diff #{Shellwords.escape(File.join("_expected", expected_file))} #{Shellwords.escape(File.join("_site", expected_file))}`
    if !$?.success?
      differences << "Expected output of #{expected_file} differs:\n#{diff}"
    end
  else
    differences << "Missing expected file: #{expected_file}"
  end
end

unexpected_files = actual_files - expected_files
unexpected_files.each do |unexpected_file|
  differences << "Unexpected file: #{unexpected_file}"
end

if !differences.empty?
  STDERR.puts "Differences between expected and actual outputs:"
  differences.each { |diff| STDERR.puts(diff) }
  exit(1)
end