node:http server throws uncatchable AddrInUse exception

[jamesdiacono]

It appears that the polyfill for Node.js's server does not correctly emit an "error" event when asked to listen on a port that is not available. To reproduce the problem, try running the following script in two separate Deno instances.

import http from "node:http";
const server = http.createServer();
server.once("error", function (error) {
    console.log("Failed to listen", error);
});
server.listen(9000, () => console.log("listening"));

The first instance logs "listening", which is correct. But the second instance crashes, instead of logging "Failed to listen" to stderr.

Reproduced in Deno v1.36.1 on MacOS.

I believe the problem is that there is no try...catch around the call to Deno.listen, which throws if the port is not available:

deno/ext/node/polyfills/http.ts

Line 1580 in 1b0e394

nextTick(() => this._serve());

deno/ext/node/polyfills/http.ts

Line 1613 in 1b0e394

this.#server = serve(

deno/ext/http/00_serve.js

Line 669 in 1b0e394

listener = listen(listenOpts);

[jamesdiacono]

Thanks!