net: `write(cb)` not called if `destroy()`:ed before `'connect'`

[ronag]

See #30839

_writeGeneric waits for 'connect'

node/lib/net.js

Line 759 in cf5ce2c

this.once('connect', function connect() {

which might never be emitted due to

node/lib/net.js

Lines 1106 to 1108 in cf5ce2c

	if (self.destroyed) {
	return;
	}

I believe this will fail:

const socket = createSocketBeforeConnect();
socket.write('asd', common.mustCall());
socket.destroy();

[ronag]

This is fixed

[lpinca]

If the expectation is that callback is called this is not fixed.

const assert = require('assert');
const net = require('net');

const socket = new net.Socket();

socket.connect({
  port: 80,
  host: 'example.com',
  lookup() {}
});

assert(socket.connecting);

let called = false;

socket.write('foo', function() {
  called = true;
});

socket.destroy();

process.on('exit', function() {
  assert(called);
});

[ronag]

Yea, we should add a test for that.

This seems related to the whole constructing state which in this case never gets resolved, i.e. _write never finishes https://github.com/nodejs/node/blob/master/lib/net.js#L763. I can dig into this once/if #29656 lands.

[lpinca]

yes, _writeGeneric() is never called as 'connect' is never emitted.

[ronag]

pending resolution to discussion in #31179

[ronag]

'use strict';

const common = require('../common');
const assert = require('assert');
const net = require('net');

const socket = new net.Socket();

socket.connect({
  port: 80,
  host: 'example.com',
  lookup() {}
});

assert(socket.connecting);

socket.write('foo', common.mustCall());
socket.destroy();

[ronag]

This requires #29656 in order to be fully resolved.