class Sinatra::ShowExceptions

def call(env)
  @app.call(env)
rescue Exception => e
  errors, env["rack.errors"] = env["rack.errors"], @@eats_errors
  if prefers_plain_text?(env)
    content_type = "text/plain"
    body = dump_exception(e)
  else
    content_type = "text/html"
    body = pretty(env, e)
  end
  env["rack.errors"] = errors
  [
    500,
    {
      "Content-Type" => content_type,
      "Content-Length" => body.bytesize.to_s
    },
    [body]
  ]
end