'use strict'; const common = require('../common'); const { Duplex, } = require('stream'); const { setTimeout } = require('timers/promises'); { class Foo extends Duplex { async _final(callback) { await setTimeout(common.platformTimeout(1)); callback(); } _read() {} } const foo = new Foo(); foo._write = common.mustCall((chunk, encoding, cb) => { cb(); }); foo.end('test', common.mustCall()); foo.on('error', common.mustNotCall()); }