net: emit "write after end" errors in the next tick

This commit makes those errors caused by calling
`net.Socket.write()` after sockets ending be emitted in the next
tick.

PR-URL: https://github.com/nodejs/node/pull/24457
Fixes: https://github.com/nodejs/node/issues/24111
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

lib/net.js

@@ -401,8 +401,7 @@ function writeAfterFIN(chunk, encoding, cb) {
   // eslint-disable-next-line no-restricted-syntax
   var er = new Error('This socket has been ended by the other party');
   er.code = 'EPIPE';
-  // TODO: defer error events consistently everywhere, not just the cb
+  process.nextTick(emitErrorNT, this, er);
-  this.emit('error', er);
   if (typeof cb === 'function') {
     defaultTriggerAsyncIdScope(this[async_id_symbol], process.nextTick, cb, er);
   }

test/parallel/test-net-write-after-end-nt.js

@@ -0,0 +1,26 @@
+'use strict';
+const common = require('../common');
+
+const assert = require('assert');
+const net = require('net');
+
+const { mustCall } = common;
+
+// This test ensures those errors caused by calling `net.Socket.write()`
+// after sockets ending will be emitted in the next tick.
+const server = net.createServer(mustCall((socket) => {
+  socket.end();
+})).listen(() => {
+  const client = net.connect(server.address().port, () => {
+    let hasError = false;
+    client.on('error', mustCall((err) => {
+      hasError = true;
+      server.close();
+    }));
+    client.on('end', mustCall(() => {
+      client.write('hello', mustCall());
+      assert(!hasError, 'The error should be emitted in the next tick.');
+    }));
+    client.end();
+  });
+});