--watch should monitor replaced files

What is the problem this feature will solve?

Currently, --watch watches an inode and not necessarily what the user might consider a "file". This can cause confusion on systems that write to disk by deleting the old file and then creating a new one.

For example, when using Docker Compose's watch mode, the watched file is first deleted. When a new file is created Node currently fails to restart on file changes, as node is still watching the inode of the deleted file, and doesn't react to the new file being created.

What is the feature you are proposing to solve the problem?

While this behavior makes sense for the lower-level and more "raw" fs.watch(), perhaps the more general --watch behavior can be expanded to be smarter about detecting replaced files. Alternatively, a new flag can be introduced with this behavior.

What alternatives have you considered?

Other alternatives require using one of the different file watcher libs. That seems like a step down from the otherwise awesome native watch feature.

Docker Compose Issue: [BUG] Compose Watch With “node –watch” Only Reloads First Time
Docker Issue: node --watch doesn't work well within a container

从 Node.js 的 --watch 实现以及 issue 中描述的 fs.watch 行为开始。重现 Docker Compose 风格的删除并重新创建序列，然后确定是否应扩展现有行为，或通过新的 flag 将其暴露出来。当被监视的文件被替换时，--watch 能够可靠地作出反应，并且包含针对替换情况的测试覆盖，即视为完成。