Bun hangs on a closed express server, Node.js works

[mindreframer]

What version of Bun is running?

1.2.12+32a47ae45

What platform is your computer?

Darwin 24.3.0 arm64 arm

What steps can reproduce the bug?

$ bun check.js

const request = require("supertest");
const express = require("express");

const app = express();

app.get("/user", function (req, res) {
  res.status(200).json({ name: "john" });
});

const server = app.listen(); // Store server instance

request(app)
  .get("/user")
  .expect("Content-Type", /json/)
  .expect("Content-Length", "15")
  .expect(200)
  .end(function (err, res) {
    if (err) throw err;
    server.close(); // Close the server when done
  });

console.log("done");

What is the expected behavior?

The express server should be closed when reaching the end of the file, which works correctly in Node.js

What do you see instead?

The script hangs, not finishing properly.
process.exit(); is harder and kills the script for sure, but it should work by closing the server instance.

Additional information

No response

[mindreframer]

found a version, that works:

const request = require("supertest");
const express = require("express");

const app = express();

app.get("/user", function (req, res) {
  res.status(200).json({ name: "john" });
});

const server = app.listen(); // Store server instance 

request(server) // <- not app, but server here!
  .get("/user")
  .expect("Content-Type", /json/)
  .expect("Content-Length", "15")
  .expect(200)
  .end(function (err, res) {
    if (err) throw err;
    server.close(); // Close the server when done
  });

console.log("done");

[cirospaciari]

Looks like server.close(); in node.js behaves a little different than bun right now, I'm are working in the compatibility of this module every day, will investigate the case

[cirospaciari]

fixed in #18962 by @nektro available in latest canary