rails--rails/railties/test/engine/commands_test.rb

require "abstract_unit"
begin
  require "pty"
rescue LoadError
end

class Rails::Engine::CommandsTest < ActiveSupport::TestCase
  def setup
    @destination_root = Dir.mktmpdir("bukkits")
    Dir.chdir(@destination_root) { `bundle exec rails plugin new bukkits --mountable` }
  end

  def teardown
    FileUtils.rm_rf(@destination_root)
  end

  def test_help_command_work_inside_engine
    output = capture(:stderr) do
      Dir.chdir(plugin_path) { `bin/rails --help` }
    end
    assert_no_match "NameError", output
  end

  def test_runner_command_work_inside_engine
    output = capture(:stdout) do
      Dir.chdir(plugin_path) { system("bin/rails runner 'puts Rails.env'") }
    end

    assert_equal "test", output.strip
  end

  def test_console_command_work_inside_engine
    skip "PTY unavailable" unless available_pty?

    master, slave = PTY.open
    spawn_command("console", slave)
    assert_output(">", master)
  ensure
    master.puts "quit"
  end

  def test_dbconsole_command_work_inside_engine
    skip "PTY unavailable" unless available_pty?

    master, slave = PTY.open
    spawn_command("dbconsole", slave)
    assert_output("sqlite>", master)
  ensure
    master.puts ".exit"
  end

  def test_server_command_work_inside_engine
    skip "PTY unavailable" unless available_pty?

    master, slave = PTY.open
    pid = spawn_command("server", slave)
    assert_output("Listening on", master)
  ensure
    kill(pid)
  end

  private
    def plugin_path
      "#{@destination_root}/bukkits"
    end

    def assert_output(expected, io, timeout = 10)
      timeout = Time.now + timeout

      output = ""
      until output.include?(expected) || Time.now > timeout
        if IO.select([io], [], [], 0.1)
          output << io.read(1)
        end
      end

      assert_includes output, expected, "#{expected.inspect} expected, but got:\n\n#{output}"
    end

    def spawn_command(command, fd)
      Process.spawn(
        "#{plugin_path}/bin/rails #{command}",
        in: fd, out: fd, err: fd
      )
    end

    def available_pty?
      defined?(PTY) && PTY.respond_to?(:open)
    end

    def kill(pid)
      Process.kill("TERM", pid)
      Process.wait(pid)
    rescue Errno::ESRCH
    end
end