`Deno.watchFs` emits events for wrong directory when multiple watchers are running

[wegrzynkiewicz]

Version: Deno: 2.7.5
System: Linux Mint Debian Edition 6 (faye), kernel 6.1.0-42-amd64 (x86_64)

Description

When running two concurrent Deno.watchFs watchers on separate directories, renaming a file in one directory causes the other watcher to emit events for that file, even though the file is not in its watched path.

Reproduction script

const path1 = `/app/assets1`
const path2 = `/app/assets2`

async function watch1() {
  console.log(`watch1 ${path1}`);
  for await (const { kind, paths } of Deno.watchFs(path1)) {
    console.log("detect 1", kind, paths)
  }
}

async function watch2() {
  console.log(`watch2 ${path2}`);
  for await (const { kind, paths } of Deno.watchFs(path2)) {
    console.log("detect 2", kind, paths)
  }
}

void watch1()
void watch2()

Steps to reproduce

• Run the script: deno run -A watch.ts
• Rename a file inside: mv /app/assets1/test.png /app/assets1/test.renamed.png

Actual output

watch1 /app/assets1
watch2 /app/assets2
detect 1 remove [ "/app/assets1/test.png" ]
detect 2 remove [ "/app/assets1/test.png" ]
detect 1 rename [ "/app/assets1/test.renamed.png" ]
detect 2 remove [ "/app/assets1/test.png", "/app/assets1/test.renamed.png" ]
detect 1 rename [ "/app/assets1/test.png", "/app/assets1/test.renamed.png" ]

Expected behavior

The watcher for /app/assets2 should not emit any events for a file change that occurred in /app/assets1. Events from detect two should only fire when files inside /app/assets2 are modified.

[dataCenter430]

Hey, @wegrzynkiewicz thanks for reporting this.
I'd love to work on this.