Incompatibility of types with recent changes in `@types/node`

[devversion]

Versions (please complete the following information):

• Chokidar version [e.g. 3.2.1 or commit hash] 3.5.3
• Node version [e.g. 12.11.0, ensure you are using the latest node.js] 18.17.1
• OS version: [e.g. Ubuntu 19.04 or MacOS 10.15 or Windows 10] Ubuntu

To Reproduce:

1. Update @types/node in this repository to e.g. latest Node v16 types: 16.18.75
2. Notice that types/index.d.ts is not properly extending fs.FSWatcher

  incorrectly implements interface 'import("fs").FSWatcher'.
  Type 'FSWatcher' is missing the following properties from type 'FSWatcher': ref, unref

Expected behavior Chokidar types should work with most recent versions of @types/node. TypeScript projects will face similar errors when building with skipLibCheck: false (which is the default)

Additional context

Change in @types/node that made this breaking change (to match Node versions) in a SemVer patch: https://github.com/DefinitelyTyped/DefinitelyTyped/pull/68300

[Semigradsky]

There is a possible quick fix - change this line https://github.com/paulmillr/chokidar/blob/5589454f3e082c5c476de11277346ee3debe5ad4/types/index.d.ts#L9 to

export class FSWatcher extends EventEmitter implements Omit<fs.FSWatcher, 'ref' | 'unref'> { 

Or define these missed methods.

[paulmillr]

so why was it fine before? maybe it’s not ours issue?

[devversion]

I don't have enough context unfortunately, but at first glance it looks like:

• fs.FSWatcher actually defines these two methods always
  • They are now typed in @types/node, and users will see those.
  • Chokidar may be validated against this version of the Node types.
• The watcher type from chokidar "implements" fs.FSWatcher but with the new interface, it does not fully implement the latest version of fs.FSWatcher.
  • This is likely fine, but the type just needs to be updated to implement a "subset" of Node's FSWatcher.

[Semigradsky]

ref and unref were added in v14.3.0, v12.20.0 to Node.js but were missed in @types/node.

• https://nodejs.org/docs/latest/api/fs.html#watcherref
• https://nodejs.org/docs/latest/api/fs.html#watcherunref

[trollspank]

For those that may come here later... when working with Capacitor their @capacitor-community/electron module (which sets up electron for Capacitor) the 'npm run build' will fail for capacitor as it uses chokidar in setup.ts.

You have been warned :) Work around until this is resolved is 'npm install @types/node@16.18.71' within your electron directory.

[uiolee]

same issue when working with @types/node@18.19.9 and newer

[Cellule]

I wasn't successful with the Omit<fs.FSWatcher, "ref" | "unref"> solution has methods returning this would not be compatible anymore.

Instead for now I'm going with this solution. Something looks off so I'm not sure enough to make a PR on this repo, but at least it unblocks me

export class FSWatcher extends EventEmitter implements fs.FSWatcher {
  ref(): never;
  unref(): never;
}

[paulmillr]

published 3.6.0