fs: fixes recursive fs.watch crash on Linux when deleting files

Signed-off-by: Matteo Collina <[email protected]>
Fixes: #52018
PR-URL: #52349
Reviewed-By: Yagiz Nizipli <[email protected]>
Reviewed-By: Moshe Atlow <[email protected]>

Author: mcollina

lib/internal/fs/recursive_watch.js

@@ -157,11 +157,16 @@ class FSWatcher extends EventEmitter {
       persistent: this.#options.persistent,
     }, (eventType, filename) => {
       const existingStat = this.#files.get(file);
-      const currentStats = statSync(file);
+      let currentStats;
 
-      this.#files.set(file, currentStats);
+      try {
+        currentStats = statSync(file);
+        this.#files.set(file, currentStats);
+      } catch {
+        // This happens if the file was removed
+      }
 
-      if (currentStats.birthtimeMs === 0 && existingStat.birthtimeMs !== 0) {
+      if (currentStats === undefined || (currentStats.birthtimeMs === 0 && existingStat.birthtimeMs !== 0)) {
         // The file is now deleted
         this.#files.delete(file);
         this.#watchers.delete(file);

test/parallel/test-fs-watch-recursive-delete.js

@@ -0,0 +1,30 @@
+'use strict';
+
+const common = require('../common');
+const tmpdir = require('../common/tmpdir');
+const fs = require('fs');
+
+if (common.isSunOS)
+  common.skip('SunOS behaves differently');
+
+tmpdir.refresh();
+
+fs.mkdirSync(tmpdir.resolve('./parent/child'), { recursive: true });
+
+fs.writeFileSync(tmpdir.resolve('./parent/child/test.tmp'), 'test');
+
+const toWatch = tmpdir.resolve('./parent');
+
+const onFileUpdate = common.mustCallAtLeast((eventType, filename) => {
+  // We are only checking for the filename to avoid having Windows, Linux and Mac specific assertions
+  if (fs.readdirSync(tmpdir.resolve('./parent')).length === 0) {
+    watcher.close();
+  }
+}, 1);
+
+const watcher = fs.watch(toWatch, { recursive: true }, onFileUpdate);
+
+// We must wait a bit `fs.rm()` to let the watcher be set up properly
+setTimeout(() => {
+  fs.rm(tmpdir.resolve('./parent/child'), { recursive: true }, common.mustCall());
+}, common.platformTimeout(500));