事件：'finish'

【Event: 'finish'】

在调用 stream.end() 方法并且所有数据已被刷新到底层系统后，会触发 'finish' 事件。

【The 'finish' event is emitted after the stream.end() method has been called, and all data has been flushed to the underlying system.】

const writer = getWritableStreamSomehow();
for (let i = 0; i < 100; i++) {
  writer.write(`hello, #${i}!\n`);
}
writer.on('finish', () => {
  console.log('All writes are now complete.');
});
writer.end('This is the end\n'); 拷贝