Method onError

packages/socket.io-client/lib/manager.ts:335–346

(err)

    });

    const onError = (err) => {
      debug(class="st">"error");
      this.cleanup();
      this._readyState = class="st">"closed";
      this.emitReserved(class="st">"error", err);
      if (fn) {
        fn(err);
      } else {
        class="cm">// Only do this if there is no fn to handle the error
        this.maybeReconnectOnOpen();
      }
    };

    class="cm">// emit `error`
    const errorSub = on(socket, class="st">"error", onError);