fixup! fixup! fs: prevent unwanted dependencyOwners removal

Author: Ceres6

test/parallel/test-watch-file-shared-dependency.mjs

@@ -0,0 +1,53 @@
+import * as common from '../common/index.mjs';
+import { describe, it } from 'node:test';
+import assert from 'node:assert';
+import tmpdir from '../common/tmpdir.js';
+import watcher from 'internal/watch_mode/files_watcher';
+import { writeFileSync } from 'node:fs';
+
+if (common.isIBMi)
+  common.skip('IBMi does not support `fs.watch()`');
+
+if (common.isAIX)
+  common.skip('folder watch capability is limited in AIX.');
+
+tmpdir.refresh();
+
+const { FilesWatcher } = watcher;
+
+tmpdir.refresh();
+
+// Set up test files and dependencies
+const fixtureContent = {
+  'dependency.js': 'module.exports = {};',
+  'test.js': 'require(\'./dependency.js\');',
+  'test-2.js': 'require(\'./dependency.js\');',
+}
+
+const fixturePaths = Object.fromEntries(Object.keys(fixtureContent)
+  .map((file) => [file, tmpdir.resolve(file)]));
+
+Object.entries(fixtureContent)
+  .forEach(([file, content]) => writeFileSync(fixturePaths[file], content));
+
+describe('watch file with shared dependency', () => {
+  it('should not remove shared dependencies when unfiltering an owner', () => {
+    const controller = new AbortController();
+    const watcher = new FilesWatcher({ signal: controller.signal, debounce: 200 });
+
+    watcher.on('changed', ({ owners }) => {
+      assert.strictEqual(owners.size, 2);
+      assert.ok(owners.has(fixturePaths['test.js']));
+      assert.ok(owners.has(fixturePaths['test-2.js']));
+      controller.abort();
+    });
+    watcher.filterFile(fixturePaths['test.js']);
+    watcher.filterFile(fixturePaths['test-2.js']);
+    watcher.filterFile(fixturePaths['dependency.js'], fixturePaths['test.js']);
+    watcher.filterFile(fixturePaths['dependency.js'], fixturePaths['test-2.js']);
+    watcher.unfilterFilesOwnedBy([fixturePaths['test.js']]);
+    watcher.filterFile(fixturePaths['test.js']);
+    watcher.filterFile(fixturePaths['dependency.js'], fixturePaths['test.js']);
+    writeFileSync(fixturePaths['dependency.js'], 'module.exports = { modified: true };');
+  });
+});