constructor (app, method, path, optHttp2) {
    super(method.toUpperCase(), path);

    if (typeof app === 'function') {
      if (optHttp2) {
        app = http2.createServer(app); // eslint-disable-line no-param-reassign
      } else {
        app = http.createServer(app); // eslint-disable-line no-param-reassign
      }
    }

    this.redirects(0);
    this.buffer();
    this.app = app;
    this._asserts = [];
    this.url = typeof app === 'string'
      ? app + path
      : this.serverAddress(app, path);
  }
Initialize a new `Test` with the given `app`,
request `method` and `path`.

@param {Server} app
@param {String} method
@param {String} path
@api public