text: module.exports = function () {
      // see https://code.google.com/p/v8/wiki/JavaScriptStackTraceApi
      var origPrepareStackTrace = Error.prepareStackTrace;
      Error.prepareStackTrace = function (_, stack) { return stack; };
      var stack = (new Error()).stack;
      Error.prepareStackTrace = origPrepareStackTrace;
      return stack[2].getFileName();
  };
  