net: handle socket.write(cb) edge case

Make sure that when calling `write()` on a connecting socket, the
callback is called if the socket is destroyed before the connection is
established.

Fixes: nodejs#30841

lib/net.js

@@ -896,8 +896,13 @@ Socket.prototype._writeGeneric = function(writev, data, encoding, cb) {
     this._pendingData = data;
     this._pendingEncoding = encoding;
     this.once('connect', function connect() {
+      this.off('close', onClose);
       this._writeGeneric(writev, data, encoding, cb);
     });
+    function onClose() {
+      cb(new ERR_SOCKET_CLOSED());
+    }
+    this.once('close', onClose);
     return;
   }
   this._pendingData = null;

test/parallel/test-net-write-cb-on-destroy.js

@@ -0,0 +1,24 @@
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const net = require('net');
+
+const server = net.createServer();
+server.listen(0, common.mustCall(() => {
+  const socket = new net.Socket();
+
+  socket.connect({
+    port: server.address().port,
+  });
+
+  assert(socket.connecting);
+
+  socket.write('foo', common.expectsError({
+    code: 'ERR_SOCKET_CLOSED',
+    name: 'Error'
+  }));
+
+  socket.destroy();
+  server.close();
+}));