denoland/deno · error · TypeError

Invalid port (expected number): ${maybePort}

Error message

Invalid port (expected number): ${maybePort}

What it means

Error "Invalid port (expected number): ${maybePort}" thrown in denoland/deno.

Source

Thrown at ext/net/01_net.js:645

    }
    case "tunnel": {
      const { 0: rid, 1: addr } = op_net_listen_tunnel();
      return new Listener(rid, addr, "tunnel");
    }
    default:
      throw new TypeError(`Unsupported transport: '${transport}'`);
  }
}

function validatePort(maybePort, isServer = false) {
  // A missing port means "any available port" (port 0) for servers. Clients
  // must always specify a port to connect to, so a missing port is left as-is
  // and rejected below.
  if (isServer && (maybePort === null || maybePort === undefined)) {
    maybePort = 0;
  }
  if (typeof maybePort !== "number" && typeof maybePort !== "string") {
    throw new TypeError(`Invalid port (expected number): ${maybePort}`);
  }
  if (maybePort === "") throw new TypeError("Invalid port: ''");
  const port = Number(maybePort);
  if (!NumberIsInteger(port)) {
    if (NumberIsNaN(port) && !NumberIsNaN(maybePort)) {
      throw new TypeError(`Invalid port: '${maybePort}'`);
    } else {
      throw new TypeError(`Invalid port: ${maybePort}`);
    }
  } else if (port < (isServer ? 0 : 1) || port > 65535) {
    // Servers may bind to port 0 (OS-assigned), clients may not connect to it.
    throw new RangeError(`Invalid port (out of range): ${maybePort}`);
  }
  return port;
}

function createListenDatagram(udpOpFn, unixOpFn) {
  return function listenDatagram(args) {

View on GitHub (pinned to 89f33cbef2)

When it happens

Trigger: Thrown at ext/net/01_net.js:645 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of denoland/deno@89f33cbef2 (2026-08-16). Data as JSON: /api/errors/4f473d66e734a8e6. Report an issue: GitHub.