v6.2.5

changelog.md

@@ -1,5 +1,81 @@
 # Changelog
 
+## 2025-12-11 - 6.2.5 - fix(watcher.node)
+Normalize paths and improve Node watcher robustness: restart/rescan on errors (including ENOSPC), clear stale state, and remove legacy throttler
+
+- Normalize all paths to absolute at watcher entry points (watchPath, handleFsEvent, scanDirectory) to avoid relative/absolute mismatch bugs
+- On watcher restart: clear pending unlink timeouts, dispose stale DirEntry data, and perform a rescan to catch files created during the restart window
+- Trigger watcher restart on ENOSPC (inotify limit) errors instead of only logging the error
+- Remove the previous Throttler implementation and rely on the existing debounce + event-sequence tracking to handle rapid events
+- Atomic write handling and queued unlink behavior preserved; pending unlinks are cleared for restarted base paths to avoid stale events
+
+## 2025-12-11 - 6.2.4 - fix(tests)
+Stabilize tests and document chokidar-inspired Node watcher architecture
+
+- test: add waitForFileEvent helper to wait for events for a specific file (reduces test flakiness)
+- test: add small delays after unlink cleanup to account for atomic/temp-file debounce windows
+- docs: expand readme.hints.md with a detailed Node watcher architecture section (DirEntry, Throttler, atomic write handling, closer registry, constants and config)
+- docs: list updated test files and coverage scenarios (inode detection, atomic writes, stress tests)
+
+## 2025-12-11 - 6.2.3 - fix(watcher.node)
+Improve handling of temporary files from atomic editor writes in Node watcher
+
+- Detect temporary files produced by atomic editor saves and attempt to map them to the real target file instead of silently skipping the event
+- Add getTempFileTarget() to extract the real file path from temp filenames (supports patterns like file.ts.tmp.PID.TIMESTAMP and generic .tmp.*)
+- When a temp-file event is seen, queue a corresponding event for the resolved real file after a short delay (50ms) to allow rename/replace to complete
+- Add logging around temp file detection and real-file checks to aid debugging
+
+## 2025-12-11 - 6.2.2 - fix(watcher.node)
+Defer events during initial scan, track full event sequences, and harden watcher shutdown
+
+- Defer fs.watch events that arrive during the initial directory scan and process them after the scan completes to avoid race conditions where watchedFiles isn't populated.
+- Debounce now tracks the full sequence of events per file (rename/change) instead of collapsing to the last event, preventing intermediate events from being lost.
+- Detect delete+recreate via inode changes and emit unlink then add when appropriate; handle rapid create+delete sequences by emitting both events.
+- During stop(), cancel pending debounced emits before flipping _isWatching and make handleFsEvent return early when watcher is stopped to prevent orphaned timeouts and post-stop emits.
+- Add verbose logging of event sequences to aid debugging of complex fs event scenarios.
+- Update tests to expect unlink + add for inode replacement scenarios.
+- Version bump from 6.2.1 → 6.2.2
+
+## 2025-12-10 - 6.2.1 - fix(watcher.node)
+Handle fs.watch close without spurious restarts; add tests and improve test runner
+
+- Prevent spurious restarts and noisy warnings on fs.watch 'close' by checking the internal isWatching flag before logging and restarting (ts/watchers/watcher.node.ts).
+- Add comprehensive test suites covering basic operations, inode-change detection, atomic writes and stress scenarios (test/test.basic.ts, test/test.inode.ts, test/test.stress.ts).
+- Remove outdated test (test/test.ts) and delete the test asset test/assets/hi.txt.
+- Update test script in package.json to enable verbose logging, write a logfile and increase timeout to 120s to reduce flakiness in test runs.
+
+## 2025-12-10 - 6.2.0 - feat(watchers)
+Improve Node watcher robustness: file-level inode tracking, abortable restarts, restart race guards, and untracked-file handling
+
+- Add file-level inode tracking to detect delete+recreate (editor atomic saves) and emit correct 'change'/'add' events
+- Make restart delays abortable via AbortController so stop() cancels pending restarts and prevents orphan watchers
+- Guard against concurrent/dual restarts with restartingPaths to avoid race conditions between health checks and error handlers
+- Emit 'unlink' for deletions of previously untracked files (files created after initial scan) and clean up inode state
+- Track file inodes during initial scan and update/cleanup inode state on events
+- Improve logging for restart/inode/delete+recreate scenarios and update documentation/readme hints to v6.2.0+
+
+## 2025-12-08 - 6.1.1 - fix(watchers/watcher.node)
+Improve Node watcher robustness: inode tracking, ENOSPC detection, enhanced health checks and temp-file handling
+
+- Track directory inodes (watchedInodes) and restart watchers if inode changes are detected (addresses stale watchers when directories are replaced).
+- Health check now validates inode stability and explicitly detects ENOSPC (inotify max_user_watches) errors, emitting errors and logging a recommended fix command.
+- Detect ENOSPC in FSWatcher error events and log guidance to increase inotify limits.
+- Clear inode tracking state on watcher stop to avoid stale state across restarts.
+- Improve temporary file handling and logging to avoid dropping events for atomic writes (only skip pure temp files and log skipped temp events).
+- Documentation (readme.hints.md) updated with robustness notes, known fs.watch limitations, and example logs.
+
+## 2025-12-08 - 6.1.0 - feat(watcher.node)
+Add automatic restart, periodic health checks, and safe event emission to Node watcher; improve logging and stat handling
+
+- NodeWatcher: introduced safeEmit() to isolate subscriber errors and prevent watcher crashes
+- Auto-restart on failure with exponential backoff (1s → 30s) and up to 3 retry attempts per watched base path
+- Periodic health checks (every 30s) to detect missing watched paths and trigger automatic restarts
+- Handle unexpected FSWatcher 'close' events and restart watchers when they close silently
+- Verbose lifecycle logging with `[smartwatch]` prefix for start/stop/health/restart events
+- Clear restart tracking and stop health checks on watcher.stop() to ensure clean shutdown
+- Improved statSafe() to normalize followSymlinks logic and log non-ENO errors as warnings
+- Updated readme.hints.md documenting the new robustness features (v6.1.0+)
+
 ## 2025-12-08 - 6.0.0 - BREAKING CHANGE(watchers)
 Replace polling-based write stabilization with debounce-based event coalescing and simplify watcher options
 

package.json

@@ -1,12 +1,12 @@
 {
   "name": "@push.rocks/smartwatch",
-  "version": "6.0.0",
+  "version": "6.2.5",
   "private": false,
   "description": "A cross-runtime file watcher with glob pattern support for Node.js, Deno, and Bun.",
   "main": "dist_ts/index.js",
   "typings": "dist_ts/index.d.ts",
   "scripts": {
-    "test": "(npm run prepareTest && tstest test/)",
+    "test": "(npm run prepareTest && tstest test/ --verbose --logfile --timeout 120)",
     "prepareTest": "(rm -f ./test/assets/hi.txt)",
     "build": "tsbuild tsfolders",
     "buildDocs": "tsdoc"

readme.hints.md

@@ -71,16 +71,164 @@ The `WriteStabilizer` class replaces chokidar's built-in write stabilization:
 - **Deno**: Works on all versions with `Deno.watchFs()`
 - **Bun**: Uses Node.js compatibility layer
 
+### Architecture (v6.3.0+) - Chokidar-Inspired
+
+The Node.js watcher has been refactored with elegant patterns inspired by [chokidar](https://github.com/paulmillr/chokidar):
+
+**DirEntry Class:**
+- Tracks directory contents with proper disposal
+- Encapsulates file tracking and inode management
+- `dispose()` method freezes object to catch use-after-cleanup bugs
+
+**Path Normalization (v6.3.1+):**
+- ALL paths are normalized to absolute at entry points
+- Prevents relative/absolute path mismatch bugs
+- `watchPath()`, `handleFsEvent()`, `scanDirectory()` all resolve paths
+
+**Restart Rescan (v6.3.1+):**
+- When watcher restarts, it rescans the directory
+- Catches files created during the restart window
+- Clears stale DirEntry data before rescan
+- Clears pending unlink timeouts to prevent stale events
+
+**ENOSPC Handling (v6.3.1+):**
+- inotify limit errors now trigger watcher restart
+- Previously only logged error without recovery
+
+**Atomic Write Handling:**
+- Unlink events are queued with 100ms delay
+- If add event arrives for same path within delay, unlink is cancelled
+- Emits single `change` event instead of `unlink` + `add`
+- Handles editor atomic saves elegantly
+
+**Closer Registry:**
+- Maps watch paths to cleanup functions
+- Ensures proper resource cleanup on stop
+- `addCloser()` / `runClosers()` pattern
+
+**Event Constants Object:**
+```typescript
+const EV = {
+  ADD: 'add',
+  CHANGE: 'change',
+  UNLINK: 'unlink',
+  ADD_DIR: 'addDir',
+  UNLINK_DIR: 'unlinkDir',
+  READY: 'ready',
+  ERROR: 'error',
+} as const;
+```
+
+**Configuration Constants:**
+```typescript
+const CONFIG = {
+  MAX_RETRIES: 3,
+  INITIAL_RESTART_DELAY: 1000,
+  MAX_RESTART_DELAY: 30000,
+  HEALTH_CHECK_INTERVAL: 30000,
+  ATOMIC_DELAY: 100,
+  TEMP_FILE_DELAY: 50,
+} as const;
+```
+
+### Robustness Features (v6.1.0+)
+
+The Node.js watcher includes automatic recovery mechanisms based on learnings from [chokidar](https://github.com/paulmillr/chokidar) and known [fs.watch issues](https://github.com/nodejs/node/issues/47058):
+
+**Auto-restart on failure:**
+- Watchers automatically restart when errors occur
+- Exponential backoff (1s → 30s max)
+- Maximum 3 retry attempts before giving up
+- **v6.2.0+**: Race condition guards prevent orphan watchers when `stop()` is called during restart
+
+**Inode tracking (critical for long-running watchers):**
+- `fs.watch()` watches the **inode**, not the path!
+- When directories are replaced (git checkout, atomic saves), the inode changes
+- Health check detects inode changes and restarts the watcher
+- **v6.2.0+**: File-level inode tracking detects delete+recreate (common editor save pattern)
+- This is the most common cause of "watcher stops working after some time"
+
+**Health check monitoring:**
+- 30-second periodic health checks
+- Detects when watched paths disappear
+- Detects inode changes (directory replacement)
+- Detects ENOSPC errors (inotify limit exceeded)
+- **v6.2.0+**: Protected against dual-restart race conditions (health check + error handler)
+
+**ENOSPC detection (Linux inotify limit):**
+- Detects when `/proc/sys/fs/inotify/max_user_watches` is exceeded
+- Logs fix command: `echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p`
+
+**Error isolation:**
+- Subscriber errors don't crash the watcher
+- All events emitted via `safeEmit()` with try-catch
+
+**Untracked file handling (v6.2.0+):**
+- Files created after initial scan are properly detected
+- Untracked file deletions emit `unlink` events instead of being silently dropped
+
+**Event Deferral During Initial Scan (v6.2.2+):**
+- Events are queued until initial scan completes
+- Prevents race conditions where events arrive before `watchedFiles` is populated
+- Deferred events are processed after scan completes
+
+**Event Sequence Tracking (v6.2.2+):**
+- Debounce now tracks ALL events in sequence, not just the last one
+- Prevents losing intermediate events (e.g., add→change→delete no longer loses add)
+- Intelligent processing of event sequences:
+  - Delete+recreate with inode change → emits `unlink` then `add`
+  - Rapid create+delete → emits both events
+  - Multiple changes → single `change` event (debouncing)
+
+**Post-Stop Event Guards (v6.2.2+):**
+- `handleFsEvent()` returns early if watcher is stopped
+- Pending emits are cleared BEFORE setting `_isWatching = false`
+- Prevents orphaned timeouts and events after `stop()`
+
+**Verbose logging:**
+- All lifecycle events logged with `[smartwatch]` prefix
+- Event sequences logged for debugging complex scenarios
+- Helps debug watcher issues in production
+
+Example log output:
+```
+[smartwatch] Starting watcher for 1 base path(s)...
+[smartwatch] Started watching: ./test/assets/
+[smartwatch] Starting health check (every 30s)
+[smartwatch] Watcher started with 1 active watcher(s)
+[smartwatch] Health check: 1 watchers active
+[smartwatch] Processing event sequence for ./src/file.ts: [rename, rename, change]
+[smartwatch] File inode changed (delete+recreate): ./src/file.ts
+[smartwatch]   Previous inode: 12345, current: 67890
+```
+
+### Known fs.watch Limitations
+
+1. **Watches inode, not path** - If a directory is replaced, watcher goes stale
+2. **inotify limits on Linux** - Default `max_user_watches` (8192) may be too low
+3. **No events for some atomic writes** - Some editors' save patterns may not trigger events
+4. **Platform differences** - Linux uses inotify, macOS uses FSEvents/kqueue
+
 ### Testing
 
 ```bash
 pnpm test
 ```
 
+Test files:
+- **test.basic.ts** - Core functionality (add, change, unlink events)
+- **test.inode.ts** - Inode change detection, atomic writes
+- **test.stress.ts** - Rapid modifications, many files, interleaved operations
+
 Tests verify:
 - Creating Smartwatch instance
 - Adding glob patterns
-- Receiving 'add' events for new files
+- Receiving 'add', 'change', 'unlink' events
+- Inode change detection (delete+recreate pattern)
+- Atomic write pattern (temp file + rename)
+- Rapid file modifications (debouncing)
+- Many files created rapidly
+- Interleaved add/change/delete operations
 - Graceful shutdown
 
 ## Dev Dependencies

test/assets/hi.txt

@@ -1 +0,0 @@
-HI

test/test.basic.ts

@@ -0,0 +1,155 @@
+import { tap, expect } from '@git.zone/tstest/tapbundle';
+import * as smartwatch from '../ts/index.js';
+import * as smartfile from '@push.rocks/smartfile';
+import * as smartrx from '@push.rocks/smartrx';
+
+import * as fs from 'fs';
+import * as path from 'path';
+
+// Skip in CI
+if (process.env.CI) {
+  process.exit(0);
+}
+
+const TEST_DIR = './test/assets';
+
+// Helper to delay
+const delay = (ms: number) => new Promise<void>((resolve) => setTimeout(resolve, ms));
+
+// Helper to wait for an event with timeout
+async function waitForEvent<T>(
+  observable: smartrx.rxjs.Observable<T>,
+  timeoutMs: number = 5000
+): Promise<T> {
+  return new Promise((resolve, reject) => {
+    const timeout = setTimeout(() => {
+      subscription.unsubscribe();
+      reject(new Error(`Timeout waiting for event after ${timeoutMs}ms`));
+    }, timeoutMs);
+
+    const subscription = observable.subscribe((value) => {
+      clearTimeout(timeout);
+      subscription.unsubscribe();
+      resolve(value);
+    });
+  });
+}
+
+// Helper to wait for a specific file's event (filters by filename)
+async function waitForFileEvent<T extends [string, ...any[]]>(
+  observable: smartrx.rxjs.Observable<T>,
+  expectedFile: string,
+  timeoutMs: number = 5000
+): Promise<T> {
+  return new Promise((resolve, reject) => {
+    const timeout = setTimeout(() => {
+      subscription.unsubscribe();
+      reject(new Error(`Timeout waiting for event on ${expectedFile} after ${timeoutMs}ms`));
+    }, timeoutMs);
+
+    const subscription = observable.subscribe((value) => {
+      const [filePath] = value;
+      if (filePath.includes(expectedFile)) {
+        clearTimeout(timeout);
+        subscription.unsubscribe();
+        resolve(value);
+      }
+      // Otherwise keep waiting for the right file
+    });
+  });
+}
+
+let testSmartwatch: smartwatch.Smartwatch;
+
+// ===========================================
+// BASIC TESTS
+// ===========================================
+
+tap.test('should create a new instance', async () => {
+  testSmartwatch = new smartwatch.Smartwatch([]);
+  expect(testSmartwatch).toBeInstanceOf(smartwatch.Smartwatch);
+});
+
+tap.test('should add paths and start watching', async () => {
+  testSmartwatch.add([`${TEST_DIR}/**/*.txt`]);
+  await testSmartwatch.start();
+  expect(testSmartwatch.status).toEqual('watching');
+});
+
+tap.test('should detect ADD event for new files', async () => {
+  const addObservable = await testSmartwatch.getObservableFor('add');
+  const eventPromise = waitForEvent(addObservable);
+
+  // Create a new file
+  const testFile = path.join(TEST_DIR, 'add-test.txt');
+  await smartfile.memory.toFs('test content', testFile);
+
+  const [filePath] = await eventPromise;
+  expect(filePath).toInclude('add-test.txt');
+
+  // Cleanup - wait for atomic delay to complete (100ms debounce + 100ms atomic)
+  await fs.promises.unlink(testFile);
+  await delay(250);
+});
+
+tap.test('should detect CHANGE event for modified files', async () => {
+  // First create the file
+  const testFile = path.join(TEST_DIR, 'change-test.txt');
+  await smartfile.memory.toFs('initial content', testFile);
+
+  // Wait for add event to complete
+  await delay(200);
+
+  const changeObservable = await testSmartwatch.getObservableFor('change');
+  const eventPromise = waitForEvent(changeObservable);
+
+  // Modify the file
+  await smartfile.memory.toFs('modified content', testFile);
+
+  const [filePath] = await eventPromise;
+  expect(filePath).toInclude('change-test.txt');
+
+  // Cleanup - wait for atomic delay to complete
+  await fs.promises.unlink(testFile);
+  await delay(250);
+});
+
+tap.test('should detect UNLINK event for deleted files', async () => {
+  // First create the file
+  const testFile = path.join(TEST_DIR, 'unlink-test.txt');
+  await smartfile.memory.toFs('to be deleted', testFile);
+
+  // Wait for add event to complete
+  await delay(200);
+
+  const unlinkObservable = await testSmartwatch.getObservableFor('unlink');
+
+  // Use file-specific wait to handle any pending unlinks from other tests
+  const eventPromise = waitForFileEvent(unlinkObservable, 'unlink-test.txt');
+
+  // Delete the file
+  await fs.promises.unlink(testFile);
+
+  const [filePath] = await eventPromise;
+  expect(filePath).toInclude('unlink-test.txt');
+});
+
+tap.test('should stop the watch process', async () => {
+  await testSmartwatch.stop();
+  expect(testSmartwatch.status).toEqual('idle');
+});
+
+tap.test('cleanup: remove any remaining test files', async () => {
+  const files = await fs.promises.readdir(TEST_DIR);
+  for (const file of files) {
+    if (file.startsWith('add-') || file.startsWith('change-') || file.startsWith('unlink-')) {
+      try {
+        await fs.promises.unlink(path.join(TEST_DIR, file));
+      } catch {
+        // Ignore
+      }
+    }
+  }
+});
+
+export default tap.start();

test/test.inode.ts

@@ -0,0 +1,135 @@
+import { tap, expect } from '@git.zone/tstest/tapbundle';
+import * as smartwatch from '../ts/index.js';
+import * as smartfile from '@push.rocks/smartfile';
+import * as smartrx from '@push.rocks/smartrx';
+
+import * as fs from 'fs';
+import * as path from 'path';
+
+// Skip in CI
+if (process.env.CI) {
+  process.exit(0);
+}
+
+const TEST_DIR = './test/assets';
+
+// Helper to delay
+const delay = (ms: number) => new Promise<void>((resolve) => setTimeout(resolve, ms));
+
+// Helper to wait for an event with timeout
+async function waitForEvent<T>(
+  observable: smartrx.rxjs.Observable<T>,
+  timeoutMs: number = 5000
+): Promise<T> {
+  return new Promise((resolve, reject) => {
+    const timeout = setTimeout(() => {
+      subscription.unsubscribe();
+      reject(new Error(`Timeout waiting for event after ${timeoutMs}ms`));
+    }, timeoutMs);
+
+    const subscription = observable.subscribe((value) => {
+      clearTimeout(timeout);
+      subscription.unsubscribe();
+      resolve(value);
+    });
+  });
+}
+
+let testSmartwatch: smartwatch.Smartwatch;
+
+// ===========================================
+// INODE CHANGE DETECTION TESTS
+// ===========================================
+
+tap.test('setup: start watcher', async () => {
+  testSmartwatch = new smartwatch.Smartwatch([`${TEST_DIR}/**/*.txt`]);
+  await testSmartwatch.start();
+  expect(testSmartwatch.status).toEqual('watching');
+});
+
+tap.test('should detect delete+recreate (inode change scenario)', async () => {
+  // This simulates what many editors do: delete file, create new file
+  const testFile = path.join(TEST_DIR, 'inode-test.txt');
+
+  // Create initial file
+  await smartfile.memory.toFs('initial content', testFile);
+  await delay(200);
+
+  // Get the initial inode
+  const initialStats = await fs.promises.stat(testFile);
+  const initialInode = initialStats.ino;
+  console.log(`[test] Initial inode: ${initialInode}`);
+
+  // With event sequence tracking, delete+recreate emits: unlink, then add
+  // This is more accurate than just emitting 'change'
+  const unlinkObservable = await testSmartwatch.getObservableFor('unlink');
+  const addObservable = await testSmartwatch.getObservableFor('add');
+  const unlinkPromise = waitForEvent(unlinkObservable, 3000);
+  const addPromise = waitForEvent(addObservable, 3000);
+
+  // Delete and recreate (this creates a new inode)
+  await fs.promises.unlink(testFile);
+  await smartfile.memory.toFs('recreated content', testFile);
+
+  // Check inode changed
+  const newStats = await fs.promises.stat(testFile);
+  const newInode = newStats.ino;
+  console.log(`[test] New inode: ${newInode}`);
+  expect(newInode).not.toEqual(initialInode);
+
+  // Should detect both unlink and add events for delete+recreate
+  const [[unlinkPath], [addPath]] = await Promise.all([unlinkPromise, addPromise]);
+  expect(unlinkPath).toInclude('inode-test.txt');
+  expect(addPath).toInclude('inode-test.txt');
+  console.log(`[test] Detected unlink + add events for delete+recreate`);
+
+  // Cleanup
+  await fs.promises.unlink(testFile);
+});
+
+tap.test('should detect atomic write pattern (temp file + rename)', async () => {
+  // This simulates what Claude Code and many editors do:
+  // 1. Write to temp file (file.txt.tmp.12345)
+  // 2. Rename temp file to target file
+  const testFile = path.join(TEST_DIR, 'atomic-test.txt');
+  const tempFile = path.join(TEST_DIR, 'atomic-test.txt.tmp.12345');
+
+  // Create initial file
+  await smartfile.memory.toFs('initial content', testFile);
+  await delay(200);
+
+  const changeObservable = await testSmartwatch.getObservableFor('change');
+  const eventPromise = waitForEvent(changeObservable, 3000);
+
+  // Atomic write: create temp file then rename
+  await smartfile.memory.toFs('atomic content', tempFile);
+  await fs.promises.rename(tempFile, testFile);
+
+  // Should detect the change to the target file
+  const [filePath] = await eventPromise;
+  expect(filePath).toInclude('atomic-test.txt');
+  expect(filePath).not.toInclude('.tmp.');
+
+  // Cleanup
+  await fs.promises.unlink(testFile);
+});
+
+tap.test('teardown: stop watcher', async () => {
+  await testSmartwatch.stop();
+  expect(testSmartwatch.status).toEqual('idle');
+});
+
+tap.test('cleanup: remove test files', async () => {
+  const files = await fs.promises.readdir(TEST_DIR);
+  for (const file of files) {
+    if (file.startsWith('inode-') || file.startsWith('atomic-')) {
+      try {
+        await fs.promises.unlink(path.join(TEST_DIR, file));
+      } catch {
+        // Ignore
+      }
+    }
+  }
+});
+
+export default tap.start();

test/test.stress.ts

@@ -0,0 +1,174 @@
+import { tap, expect } from '@git.zone/tstest/tapbundle';
+import * as smartwatch from '../ts/index.js';
+import * as smartfile from '@push.rocks/smartfile';
+import * as smartrx from '@push.rocks/smartrx';
+
+import * as fs from 'fs';
+import * as path from 'path';
+
+// Skip in CI
+if (process.env.CI) {
+  process.exit(0);
+}
+
+const TEST_DIR = './test/assets';
+
+// Helper to delay
+const delay = (ms: number) => new Promise<void>((resolve) => setTimeout(resolve, ms));
+
+// Helper to collect events
+function collectEvents<T>(
+  observable: smartrx.rxjs.Observable<T>,
+  durationMs: number
+): Promise<T[]> {
+  return new Promise((resolve) => {
+    const events: T[] = [];
+    const subscription = observable.subscribe((value) => {
+      events.push(value);
+    });
+
+    setTimeout(() => {
+      subscription.unsubscribe();
+      resolve(events);
+    }, durationMs);
+  });
+}
+
+let testSmartwatch: smartwatch.Smartwatch;
+
+// ===========================================
+// STRESS TESTS
+// ===========================================
+
+tap.test('setup: start watcher', async () => {
+  testSmartwatch = new smartwatch.Smartwatch([`${TEST_DIR}/**/*.txt`]);
+  await testSmartwatch.start();
+  expect(testSmartwatch.status).toEqual('watching');
+});
+
+tap.test('STRESS: rapid file modifications', async () => {
+  const testFile = path.join(TEST_DIR, 'stress-rapid.txt');
+
+  // Create initial file
+  await smartfile.memory.toFs('initial', testFile);
+  await delay(200);
+
+  const changeObservable = await testSmartwatch.getObservableFor('change');
+
+  // Rapidly modify the file 20 times
+  const RAPID_CHANGES = 20;
+  const eventCollector = collectEvents(changeObservable, 3000);
+
+  for (let i = 0; i < RAPID_CHANGES; i++) {
+    await smartfile.memory.toFs(`content ${i}`, testFile);
+    await delay(10); // 10ms between writes
+  }
+
+  const events = await eventCollector;
+  console.log(`[test] Rapid changes: sent ${RAPID_CHANGES}, received ${events.length} events`);
+
+  // Due to debouncing, we won't get all events, but we should get at least some
+  expect(events.length).toBeGreaterThan(0);
+
+  // Cleanup
+  await fs.promises.unlink(testFile);
+});
+
+tap.test('STRESS: many files created rapidly', async () => {
+  const FILE_COUNT = 20;
+  const files: string[] = [];
+
+  const addObservable = await testSmartwatch.getObservableFor('add');
+  const eventCollector = collectEvents(addObservable, 5000);
+
+  // Create many files rapidly
+  for (let i = 0; i < FILE_COUNT; i++) {
+    const file = path.join(TEST_DIR, `stress-many-${i}.txt`);
+    files.push(file);
+    await smartfile.memory.toFs(`content ${i}`, file);
+    await delay(20); // 20ms between creates
+  }
+
+  const events = await eventCollector;
+  console.log(`[test] Many files: created ${FILE_COUNT}, detected ${events.length} events`);
+
+  // Should detect most or all files
+  expect(events.length).toBeGreaterThanOrEqual(FILE_COUNT * 0.8); // Allow 20% tolerance
+
+  // Cleanup all files
+  for (const file of files) {
+    try {
+      await fs.promises.unlink(file);
+    } catch {
+      // Ignore if already deleted
+    }
+  }
+});
+
+tap.test('STRESS: interleaved add/change/delete operations', async () => {
+  const testFiles = [
+    path.join(TEST_DIR, 'stress-interleave-1.txt'),
+    path.join(TEST_DIR, 'stress-interleave-2.txt'),
+    path.join(TEST_DIR, 'stress-interleave-3.txt'),
+  ];
+
+  // Create initial files
+  for (const file of testFiles) {
+    await smartfile.memory.toFs('initial', file);
+  }
+  await delay(300);
+
+  const addObservable = await testSmartwatch.getObservableFor('add');
+  const changeObservable = await testSmartwatch.getObservableFor('change');
+  const unlinkObservable = await testSmartwatch.getObservableFor('unlink');
+
+  const addEvents = collectEvents(addObservable, 3000);
+  const changeEvents = collectEvents(changeObservable, 3000);
+  const unlinkEvents = collectEvents(unlinkObservable, 3000);
+
+  // Interleaved operations
+  await smartfile.memory.toFs('changed 1', testFiles[0]); // change
+  await delay(50);
+  await fs.promises.unlink(testFiles[1]); // delete
+  await delay(50);
+  await smartfile.memory.toFs('recreated 1', testFiles[1]); // add (recreate)
+  await delay(50);
+  await smartfile.memory.toFs('changed 2', testFiles[2]); // change
+  await delay(50);
+
+  const [adds, changes, unlinks] = await Promise.all([addEvents, changeEvents, unlinkEvents]);
+
+  console.log(`[test] Interleaved: adds=${adds.length}, changes=${changes.length}, unlinks=${unlinks.length}`);
+
+  // Should have detected some events of each type
+  expect(changes.length).toBeGreaterThan(0);
+
+  // Cleanup
+  for (const file of testFiles) {
+    try {
+      await fs.promises.unlink(file);
+    } catch {
+      // Ignore
+    }
+  }
+});
+
+tap.test('teardown: stop watcher', async () => {
+  await testSmartwatch.stop();
+  expect(testSmartwatch.status).toEqual('idle');
+});
+
+tap.test('cleanup: remove stress test files', async () => {
+  const files = await fs.promises.readdir(TEST_DIR);
+  for (const file of files) {
+    if (file.startsWith('stress-')) {
+      try {
+        await fs.promises.unlink(path.join(TEST_DIR, file));
+      } catch {
+        // Ignore
+      }
+    }
+  }
+});
+
+export default tap.start();

test/test.ts

@@ -1,50 +0,0 @@
-import { tap, expect } from '@git.zone/tstest/tapbundle';
-import * as smartwatch from '../ts/index.js';
-import * as smartfile from '@push.rocks/smartfile';
-import * as smartpromise from '@push.rocks/smartpromise';
-import * as smartrx from '@push.rocks/smartrx';
-
-import * as fs from 'fs';
-
-// the module to test
-if (process.env.CI) {
-  process.exit(0);
-}
-
-let testSmartwatch: smartwatch.Smartwatch;
-let testAddObservable: smartrx.rxjs.Observable<[string, fs.Stats]>;
-let testSubscription: smartrx.rxjs.Subscription;
-tap.test('should create a new instance', async () => {
-  testSmartwatch = new smartwatch.Smartwatch([]);
-  expect(testSmartwatch).toBeInstanceOf(smartwatch.Smartwatch);
-});
-
-tap.test('should add some files to watch and start', async () => {
-  testSmartwatch.add(['./test/**/*.txt']);
-  await testSmartwatch.start()
-  testSmartwatch.add(['./test/**/*.md']);
-});
-
-tap.test('should get an observable for a certain event', async () => {
-  await testSmartwatch.getObservableFor('add').then(async (observableArg) => {
-    testAddObservable = observableArg;
-  });
-});
-
-tap.test('should register an add operation', async () => {
-  let testDeferred = smartpromise.defer();
-  testSubscription = testAddObservable.subscribe(pathArg => {
-    const pathResult = pathArg[0];
-    console.log(pathResult);
-    testDeferred.resolve();
-  });
-  smartfile.memory.toFs('HI', './test/assets/hi.txt');
-  await testDeferred.promise;
-});
-
-tap.test('should stop the watch process', async (tools) => {
-  await tools.delayFor(10000);
-  testSmartwatch.stop();
-});
-
-export default tap.start();

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@push.rocks/smartwatch',
-  version: '6.0.0',
+  version: '6.2.5',
   description: 'A cross-runtime file watcher with glob pattern support for Node.js, Deno, and Bun.'
 }

ts/watchers/watcher.node.ts

@@ -3,216 +3,614 @@ import * as path from 'path';
 import * as smartrx from '@push.rocks/smartrx';
 import type { IWatcher, IWatcherOptions, IWatchEvent, TWatchEventType } from './interfaces.js';
 
+// =============================================================================
+// Constants
+// =============================================================================
+
+/** Event type constants - inspired by chokidar's pattern */
+const EV = {
+  ADD: 'add',
+  CHANGE: 'change',
+  UNLINK: 'unlink',
+  ADD_DIR: 'addDir',
+  UNLINK_DIR: 'unlinkDir',
+  READY: 'ready',
+  ERROR: 'error',
+} as const;
+
+/** Configuration constants */
+const CONFIG = {
+  MAX_RETRIES: 3,
+  INITIAL_RESTART_DELAY: 1000,
+  MAX_RESTART_DELAY: 30000,
+  HEALTH_CHECK_INTERVAL: 30000,
+  ATOMIC_DELAY: 100,
+  TEMP_FILE_DELAY: 50,
+} as const;
+
+// =============================================================================
+// DirEntry Class - Elegant directory content tracking (inspired by chokidar)
+// =============================================================================
+
+
+/**
+ * Tracks contents of a watched directory with proper disposal
+ */
+class DirEntry {
+  private _path: string;
+  private _items: Set<string>;
+  private _inodes: Map<string, bigint>;
+
+  constructor(dirPath: string) {
+    this._path = dirPath;
+    this._items = new Set();
+    this._inodes = new Map();
+  }
+
+  get path(): string {
+    return this._path;
+  }
+
+  add(item: string, inode?: bigint): void {
+    if (item === '.' || item === '..') return;
+    this._items.add(item);
+    if (inode !== undefined) {
+      this._inodes.set(item, inode);
+    }
+  }
+
+  remove(item: string): void {
+    this._items.delete(item);
+    this._inodes.delete(item);
+  }
+
+  has(item: string): boolean {
+    return this._items.has(item);
+  }
+
+  getInode(item: string): bigint | undefined {
+    return this._inodes.get(item);
+  }
+
+  setInode(item: string, inode: bigint): void {
+    this._inodes.set(item, inode);
+  }
+
+  getChildren(): string[] {
+    return [...this._items];
+  }
+
+  get size(): number {
+    return this._items.size;
+  }
+
+  dispose(): void {
+    this._items.clear();
+    this._inodes.clear();
+    this._path = '';
+    // Freeze to catch accidental use after disposal
+    Object.freeze(this);
+  }
+}
+
+// =============================================================================
+// NodeWatcher Class
+// =============================================================================
+
 /**
  * Node.js/Bun file watcher using native fs.watch API
+ *
+ * Architecture inspired by chokidar with additional robustness features:
+ * - Event deferral during initial scan
+ * - Event sequence tracking for debounce
+ * - Atomic write handling (unlink→add becomes change)
+ * - Inode tracking for delete+recreate detection
+ * - Health check monitoring
+ * - Auto-restart with exponential backoff
  */
 export class NodeWatcher implements IWatcher {
+  // Core state
   private watchers: Map<string, fs.FSWatcher> = new Map();
-  private watchedFiles: Set<string> = new Set();
+  private watched: Map<string, DirEntry> = new Map();
   private _isWatching = false;
 
-  // Debounce: pending emits per file path
-  private pendingEmits: Map<string, NodeJS.Timeout> = new Map();
-
+  // Event stream
   public readonly events$ = new smartrx.rxjs.Subject<IWatchEvent>();
 
-  constructor(private options: IWatcherOptions) {}
+  // Atomic write handling - pending unlinks that may become changes
+  private pendingUnlinks: Map<string, { timeout: NodeJS.Timeout; event: IWatchEvent }> = new Map();
 
-  /**
-   * Check if a file is a temporary file created by editors
-   */
-  private isTemporaryFile(filePath: string): boolean {
-    const basename = path.basename(filePath);
-    // Editor temp files: *.tmp.*, *.swp, *.swx, *~, .#*
-    if (basename.includes('.tmp.')) return true;
-    if (basename.endsWith('.swp') || basename.endsWith('.swx')) return true;
-    if (basename.endsWith('~')) return true;
-    if (basename.startsWith('.#')) return true;
-    return false;
-  }
+  // Debounce with event sequence tracking
+  private pendingEmits: Map<string, {
+    timeout: NodeJS.Timeout;
+    events: Array<'rename' | 'change'>;
+  }> = new Map();
+
+  // Restart management
+  private restartDelays: Map<string, number> = new Map();
+  private restartAttempts: Map<string, number> = new Map();
+  private restartAbortControllers: Map<string, AbortController> = new Map();
+  private restartingPaths: Set<string> = new Set();
+
+  // Health monitoring
+  private healthCheckInterval: NodeJS.Timeout | null = null;
+  private watchedInodes: Map<string, bigint> = new Map();
+
+  // Initial scan state
+  private initialScanComplete = false;
+  private deferredEvents: Array<{ basePath: string; filename: string; eventType: string }> = [];
+
+  // Closer registry - inspired by chokidar for clean resource management
+  private closers: Map<string, Array<() => void>> = new Map();
+
+  constructor(private options: IWatcherOptions) {}
 
   get isWatching(): boolean {
     return this._isWatching;
   }
 
+  // ===========================================================================
+  // Public API
+  // ===========================================================================
+
   async start(): Promise<void> {
-    if (this._isWatching) {
-      return;
-    }
+    if (this._isWatching) return;
+
+    console.log(`[smartwatch] Starting watcher for ${this.options.basePaths.length} base path(s)...`);
 
     try {
-      // Start watching each base path
+      // Reset state
+      this.initialScanComplete = false;
+      this.deferredEvents = [];
+
+      // Start watching each base path (events will be deferred)
       for (const basePath of this.options.basePaths) {
-        await this.watchPath(basePath, 0);
+        await this.watchPath(basePath);
       }
 
       this._isWatching = true;
+      this.startHealthCheck();
 
-      // Perform initial scan to emit 'add' events for existing files
+      // Initial scan populates watched entries
       for (const basePath of this.options.basePaths) {
         await this.scanDirectory(basePath, 0);
       }
 
-      // Emit ready event
-      this.events$.next({ type: 'ready', path: '' });
+      // Process deferred events
+      this.initialScanComplete = true;
+      if (this.deferredEvents.length > 0) {
+        console.log(`[smartwatch] Processing ${this.deferredEvents.length} deferred events`);
+        for (const event of this.deferredEvents) {
+          this.handleFsEvent(event.basePath, event.filename, event.eventType);
+        }
+        this.deferredEvents = [];
+      }
+
+      this.safeEmit({ type: EV.READY, path: '' });
+      console.log(`[smartwatch] Watcher started with ${this.watchers.size} active watcher(s)`);
     } catch (error: any) {
-      this.events$.next({ type: 'error', path: '', error });
+      console.error('[smartwatch] Failed to start watcher:', error);
+      this.safeEmit({ type: EV.ERROR, path: '', error });
       throw error;
     }
   }
 
   async stop(): Promise<void> {
-    this._isWatching = false;
+    console.log('[smartwatch] Stopping watcher...');
 
-    // Cancel all pending debounced emits
-    for (const timeout of this.pendingEmits.values()) {
-      clearTimeout(timeout);
+    // Cancel pending emits first (before flag changes)
+    for (const pending of this.pendingEmits.values()) {
+      clearTimeout(pending.timeout);
     }
     this.pendingEmits.clear();
 
-    // Close all watchers
-    for (const [, watcher] of this.watchers) {
-      watcher.close();
+    // Cancel pending unlinks
+    for (const pending of this.pendingUnlinks.values()) {
+      clearTimeout(pending.timeout);
     }
+    this.pendingUnlinks.clear();
+
+    // Now set flag
+    this._isWatching = false;
+
+    this.stopHealthCheck();
+
+    // Abort pending restarts
+    for (const [watchPath, controller] of this.restartAbortControllers) {
+      console.log(`[smartwatch] Aborting pending restart for: ${watchPath}`);
+      controller.abort();
+    }
+    this.restartAbortControllers.clear();
+
+    // Close all watchers and run closers
+    for (const [watchPath, watcher] of this.watchers) {
+      console.log(`[smartwatch] Closing watcher for: ${watchPath}`);
+      watcher.close();
+      this.runClosers(watchPath);
+    }
+
+    // Clear all state
     this.watchers.clear();
-    this.watchedFiles.clear();
+    this.watched.forEach(entry => entry.dispose());
+    this.watched.clear();
+    this.restartDelays.clear();
+    this.restartAttempts.clear();
+    this.watchedInodes.clear();
+    this.restartingPaths.clear();
+    this.closers.clear();
+
+    // Reset scan state
+    this.initialScanComplete = false;
+    this.deferredEvents = [];
+
+    console.log('[smartwatch] Watcher stopped');
+  }
+
+  // ===========================================================================
+  // Event Emission
+  // ===========================================================================
+
+  /** Safely emit an event, isolating subscriber errors */
+  private safeEmit(event: IWatchEvent): void {
+    try {
+      this.events$.next(event);
+    } catch (error) {
+      console.error('[smartwatch] Subscriber threw error (isolated):', error);
+    }
+  }
+
+  // ===========================================================================
+  // Closer Registry - Clean resource management
+  // ===========================================================================
+
+  private addCloser(watchPath: string, closer: () => void): void {
+    let list = this.closers.get(watchPath);
+    if (!list) {
+      list = [];
+      this.closers.set(watchPath, list);
+    }
+    list.push(closer);
+  }
+
+  private runClosers(watchPath: string): void {
+    const list = this.closers.get(watchPath);
+    if (list) {
+      list.forEach(closer => closer());
+      this.closers.delete(watchPath);
+    }
+  }
+
+  // ===========================================================================
+  // Directory Entry Management
+  // ===========================================================================
+
+  private getWatchedDir(dirPath: string): DirEntry {
+    const resolved = path.resolve(dirPath);
+    let entry = this.watched.get(resolved);
+    if (!entry) {
+      entry = new DirEntry(resolved);
+      this.watched.set(resolved, entry);
+    }
+    return entry;
+  }
+
+  private isTracked(filePath: string): boolean {
+    const dir = path.dirname(filePath);
+    const base = path.basename(filePath);
+    const entry = this.watched.get(path.resolve(dir));
+    return entry?.has(base) ?? false;
+  }
+
+  private trackFile(filePath: string, inode?: bigint): void {
+    const dir = path.dirname(filePath);
+    const base = path.basename(filePath);
+    this.getWatchedDir(dir).add(base, inode);
+  }
+
+  private untrackFile(filePath: string): void {
+    const dir = path.dirname(filePath);
+    const base = path.basename(filePath);
+    const entry = this.watched.get(path.resolve(dir));
+    entry?.remove(base);
+  }
+
+  private getFileInode(filePath: string): bigint | undefined {
+    const dir = path.dirname(filePath);
+    const base = path.basename(filePath);
+    const entry = this.watched.get(path.resolve(dir));
+    return entry?.getInode(base);
+  }
+
+  // ===========================================================================
+  // Temp File Handling
+  // ===========================================================================
+
+  private isTemporaryFile(filePath: string): boolean {
+    const basename = path.basename(filePath);
+    return (
+      basename.includes('.tmp.') ||
+      basename.endsWith('.swp') ||
+      basename.endsWith('.swx') ||
+      basename.endsWith('~') ||
+      basename.startsWith('.#')
+    );
   }
 
   /**
-   * Start watching a path (file or directory)
+   * Extract real file path from temp file (Claude Code atomic writes)
+   * Pattern: file.ts.tmp.PID.TIMESTAMP -> file.ts
    */
-  private async watchPath(watchPath: string, depth: number): Promise<void> {
-    if (depth > this.options.depth) {
-      return;
+  private getTempFileTarget(tempPath: string): string | null {
+    const basename = path.basename(tempPath);
+
+    // Claude Code: file.ts.tmp.PID.TIMESTAMP
+    const claudeMatch = basename.match(/^(.+)\.tmp\.\d+\.\d+$/);
+    if (claudeMatch) {
+      return path.join(path.dirname(tempPath), claudeMatch[1]);
     }
 
+    // Generic: file.ts.tmp.something
+    const genericMatch = basename.match(/^(.+)\.tmp\.[^.]+$/);
+    if (genericMatch) {
+      return path.join(path.dirname(tempPath), genericMatch[1]);
+    }
+
+    return null;
+  }
+
+  // ===========================================================================
+  // Watch Path Setup
+  // ===========================================================================
+
+  private async watchPath(watchPath: string): Promise<void> {
+    // Normalize path to absolute - critical for consistent lookups
+    watchPath = path.resolve(watchPath);
+
     try {
       const stats = await this.statSafe(watchPath);
-      if (!stats) {
-        return;
-      }
+      if (!stats?.isDirectory()) return;
 
-      if (stats.isDirectory()) {
-        // Watch the directory with recursive option (Node.js 20+ supports this on all platforms)
-        const watcher = fs.watch(
-          watchPath,
-          { recursive: true, persistent: true },
-          (eventType, filename) => {
-            if (filename) {
-              this.handleFsEvent(watchPath, filename, eventType);
-            }
+      // Store inode for health check (fs.watch watches inode, not path!)
+      this.watchedInodes.set(watchPath, BigInt(stats.ino));
+
+      const watcher = fs.watch(
+        watchPath,
+        { recursive: true, persistent: true },
+        (eventType, filename) => {
+          if (filename) {
+            this.handleFsEvent(watchPath, filename, eventType);
           }
-        );
+        }
+      );
 
-        watcher.on('error', (error) => {
-          this.events$.next({ type: 'error', path: watchPath, error });
-        });
+      watcher.on('error', (error: NodeJS.ErrnoException) => {
+        console.error(`[smartwatch] FSWatcher error on ${watchPath}:`, error);
 
-        this.watchers.set(watchPath, watcher);
-      }
+        if (error.code === 'ENOSPC') {
+          console.error('[smartwatch] CRITICAL: inotify watch limit exceeded!');
+          console.error('[smartwatch] Fix: echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p');
+        }
+
+        this.safeEmit({ type: EV.ERROR, path: watchPath, error });
+        if (this._isWatching) {
+          this.restartWatcher(watchPath, error);
+        }
+      });
+
+      watcher.on('close', () => {
+        if (this._isWatching) {
+          console.warn(`[smartwatch] FSWatcher closed unexpectedly for ${watchPath}`);
+          this.restartWatcher(watchPath, new Error('Watcher closed unexpectedly'));
+        }
+      });
+
+      this.watchers.set(watchPath, watcher);
+
+      // Register closer
+      this.addCloser(watchPath, () => {
+        try { watcher.close(); } catch {}
+      });
+
+      console.log(`[smartwatch] Started watching: ${watchPath}`);
     } catch (error: any) {
-      this.events$.next({ type: 'error', path: watchPath, error });
+      console.error(`[smartwatch] Failed to watch path ${watchPath}:`, error);
+      this.safeEmit({ type: EV.ERROR, path: watchPath, error });
     }
   }
 
-  /**
-   * Handle raw fs.watch events - debounce and normalize them
-   */
+  // ===========================================================================
+  // Event Handling
+  // ===========================================================================
+
   private handleFsEvent(
     basePath: string,
     filename: string,
     eventType: 'rename' | 'change' | string
   ): void {
-    const fullPath = path.join(basePath, filename);
+    // Guard against post-stop events
+    if (!this._isWatching) return;
 
-    // Skip temporary files created by editors (atomic saves)
-    if (this.isTemporaryFile(fullPath)) {
+    // Defer events until initial scan completes
+    if (!this.initialScanComplete) {
+      this.deferredEvents.push({ basePath, filename, eventType });
       return;
     }
 
-    // Debounce: cancel any pending emit for this file
-    const existing = this.pendingEmits.get(fullPath);
-    if (existing) {
-      clearTimeout(existing);
+    // Normalize to absolute path - critical for consistent lookups
+    const fullPath = path.resolve(path.join(basePath, filename));
+
+    // Handle temp files from atomic writes
+    if (this.isTemporaryFile(fullPath)) {
+      console.log(`[smartwatch] Detected temp file event: ${filename}`);
+      const realPath = this.getTempFileTarget(fullPath);
+      if (realPath) {
+        console.log(`[smartwatch] Checking corresponding real file: ${realPath}`);
+        setTimeout(() => {
+          if (this._isWatching) {
+            this.handleFsEvent(basePath, path.relative(basePath, realPath), 'change');
+          }
+        }, CONFIG.TEMP_FILE_DELAY);
+      }
+      return;
     }
 
-    // Schedule debounced emit
-    const timeout = setTimeout(() => {
-      this.pendingEmits.delete(fullPath);
-      this.emitFileEvent(fullPath, eventType);
-    }, this.options.debounceMs);
+    // Track event sequence for intelligent debouncing
+    const existing = this.pendingEmits.get(fullPath);
+    if (existing) {
+      clearTimeout(existing.timeout);
+      existing.events.push(eventType as 'rename' | 'change');
+      existing.timeout = setTimeout(() => {
+        const pending = this.pendingEmits.get(fullPath);
+        if (pending) {
+          this.pendingEmits.delete(fullPath);
+          this.emitFileEvent(fullPath, pending.events);
+        }
+      }, this.options.debounceMs);
+    } else {
+      const timeout = setTimeout(() => {
+        const pending = this.pendingEmits.get(fullPath);
+        if (pending) {
+          this.pendingEmits.delete(fullPath);
+          this.emitFileEvent(fullPath, pending.events);
+        }
+      }, this.options.debounceMs);
 
-    this.pendingEmits.set(fullPath, timeout);
+      this.pendingEmits.set(fullPath, {
+        timeout,
+        events: [eventType as 'rename' | 'change'],
+      });
+    }
   }
 
   /**
-   * Emit the actual file event after debounce
+   * Emit file event after debounce with atomic write handling
+   *
+   * Atomic write pattern (inspired by chokidar):
+   * - unlink event queued with delay
+   * - if add arrives for same path, transform to change
    */
   private async emitFileEvent(
     fullPath: string,
-    eventType: 'rename' | 'change' | string
+    eventSequence: Array<'rename' | 'change'>
   ): Promise<void> {
     try {
       const stats = await this.statSafe(fullPath);
+      const wasTracked = this.isTracked(fullPath);
+      const previousInode = this.getFileInode(fullPath);
 
-      if (eventType === 'rename') {
-        // 'rename' can mean add or unlink - check if file exists
-        if (stats) {
-          // File exists - it's either a new file or was renamed to this location
-          if (stats.isDirectory()) {
-            if (!this.watchedFiles.has(fullPath)) {
-              this.watchedFiles.add(fullPath);
-              this.events$.next({ type: 'addDir', path: fullPath, stats });
-            }
-          } else {
-            const wasWatched = this.watchedFiles.has(fullPath);
-            this.watchedFiles.add(fullPath);
-            this.events$.next({
-              type: wasWatched ? 'change' : 'add',
-              path: fullPath,
-              stats
-            });
+      // Analyze event sequence
+      const hasRename = eventSequence.includes('rename');
+      const renameCount = eventSequence.filter(e => e === 'rename').length;
+
+      if (eventSequence.length > 1) {
+        console.log(`[smartwatch] Processing event sequence for ${fullPath}: [${eventSequence.join(', ')}]`);
+      }
+
+      if (stats) {
+        // File EXISTS
+        const currentInode = BigInt(stats.ino);
+        const inodeChanged = previousInode !== undefined && previousInode !== currentInode;
+
+        if (stats.isDirectory()) {
+          if (!wasTracked) {
+            this.trackFile(fullPath);
+            this.safeEmit({ type: EV.ADD_DIR, path: fullPath, stats });
           }
         } else {
-          // File doesn't exist - it was deleted
-          if (this.watchedFiles.has(fullPath)) {
-            const wasDir = this.isKnownDirectory(fullPath);
-            this.watchedFiles.delete(fullPath);
-            this.events$.next({
-              type: wasDir ? 'unlinkDir' : 'unlink',
-              path: fullPath
-            });
+          // Update tracking
+          this.trackFile(fullPath, currentInode);
+
+          // Check for pending unlink → transform to change (atomic write pattern)
+          const pendingUnlink = this.pendingUnlinks.get(fullPath);
+          if (pendingUnlink) {
+            clearTimeout(pendingUnlink.timeout);
+            this.pendingUnlinks.delete(fullPath);
+            console.log(`[smartwatch] Atomic write detected (unlink→add→change): ${fullPath}`);
+            this.safeEmit({ type: EV.CHANGE, path: fullPath, stats });
+            return;
+          }
+
+          if (!wasTracked) {
+            this.safeEmit({ type: EV.ADD, path: fullPath, stats });
+          } else if (inodeChanged) {
+            console.log(`[smartwatch] File inode changed (delete+recreate): ${fullPath}`);
+            console.log(`[smartwatch]   Previous inode: ${previousInode}, current: ${currentInode}`);
+
+            if (renameCount >= 2) {
+              // Multiple renames with inode change = delete+recreate
+              this.safeEmit({ type: EV.UNLINK, path: fullPath });
+              this.safeEmit({ type: EV.ADD, path: fullPath, stats });
+            } else {
+              // Single rename with inode change = atomic save
+              this.safeEmit({ type: EV.CHANGE, path: fullPath, stats });
+            }
+          } else {
+            // Debounce already handles rapid events - no extra throttle needed
+            this.safeEmit({ type: EV.CHANGE, path: fullPath, stats });
           }
         }
-      } else if (eventType === 'change') {
-        // File was modified
-        if (stats && !stats.isDirectory()) {
-          const wasWatched = this.watchedFiles.has(fullPath);
-          if (!wasWatched) {
-            // This is actually an 'add' - file wasn't being watched before
-            this.watchedFiles.add(fullPath);
-            this.events$.next({ type: 'add', path: fullPath, stats });
+      } else {
+        // File does NOT exist - handle unlink
+        const wasDir = this.isKnownDirectory(fullPath);
+
+        if (wasTracked) {
+          this.untrackFile(fullPath);
+
+          if (renameCount >= 2 && !wasDir) {
+            // Rapid create+delete
+            console.log(`[smartwatch] File created and deleted rapidly: ${fullPath}`);
+            this.safeEmit({ type: EV.ADD, path: fullPath });
+            this.safeEmit({ type: EV.UNLINK, path: fullPath });
           } else {
-            this.events$.next({ type: 'change', path: fullPath, stats });
+            // Queue unlink with delay for atomic write detection
+            this.queueUnlink(fullPath, wasDir);
+          }
+        } else {
+          if (renameCount >= 2) {
+            console.log(`[smartwatch] Untracked file created and deleted: ${fullPath}`);
+            this.safeEmit({ type: EV.ADD, path: fullPath });
+            this.safeEmit({ type: EV.UNLINK, path: fullPath });
+          } else if (hasRename) {
+            console.log(`[smartwatch] Untracked file deleted: ${fullPath}`);
+            this.queueUnlink(fullPath, false);
           }
-        } else if (!stats && this.watchedFiles.has(fullPath)) {
-          // File was deleted
-          this.watchedFiles.delete(fullPath);
-          this.events$.next({ type: 'unlink', path: fullPath });
         }
       }
     } catch (error: any) {
-      this.events$.next({ type: 'error', path: fullPath, error });
+      this.safeEmit({ type: EV.ERROR, path: fullPath, error });
     }
   }
 
   /**
-   * Scan directory and emit 'add' events for existing files
+   * Queue an unlink event with delay for atomic write detection
+   * If add event arrives within delay, unlink is cancelled and change is emitted
    */
+  private queueUnlink(fullPath: string, isDir: boolean): void {
+    const event: IWatchEvent = {
+      type: isDir ? EV.UNLINK_DIR : EV.UNLINK,
+      path: fullPath,
+    };
+
+    const timeout = setTimeout(() => {
+      const pending = this.pendingUnlinks.get(fullPath);
+      if (pending) {
+        this.pendingUnlinks.delete(fullPath);
+        this.safeEmit(pending.event);
+      }
+    }, CONFIG.ATOMIC_DELAY);
+
+    this.pendingUnlinks.set(fullPath, { timeout, event });
+  }
+
+  // ===========================================================================
+  // Directory Scanning
+  // ===========================================================================
+
   private async scanDirectory(dirPath: string, depth: number): Promise<void> {
-    if (depth > this.options.depth) {
-      return;
-    }
+    // Normalize path to absolute - critical for consistent lookups
+    dirPath = path.resolve(dirPath);
+
+    if (depth > this.options.depth) return;
 
     try {
       const entries = await fs.promises.readdir(dirPath, { withFileTypes: true });
@@ -220,58 +618,188 @@ export class NodeWatcher implements IWatcher {
       for (const entry of entries) {
         const fullPath = path.join(dirPath, entry.name);
 
-        // Skip temp files during initial scan too
-        if (this.isTemporaryFile(fullPath)) {
-          continue;
-        }
+        if (this.isTemporaryFile(fullPath)) continue;
 
         const stats = await this.statSafe(fullPath);
-
-        if (!stats) {
-          continue;
-        }
+        if (!stats) continue;
 
         if (entry.isDirectory()) {
-          this.watchedFiles.add(fullPath);
-          this.events$.next({ type: 'addDir', path: fullPath, stats });
+          this.trackFile(fullPath);
+          this.safeEmit({ type: EV.ADD_DIR, path: fullPath, stats });
           await this.scanDirectory(fullPath, depth + 1);
         } else if (entry.isFile()) {
-          this.watchedFiles.add(fullPath);
-          this.events$.next({ type: 'add', path: fullPath, stats });
+          this.trackFile(fullPath, BigInt(stats.ino));
+          this.safeEmit({ type: EV.ADD, path: fullPath, stats });
         }
       }
     } catch (error: any) {
       if (error.code !== 'ENOENT' && error.code !== 'EACCES') {
-        this.events$.next({ type: 'error', path: dirPath, error });
+        this.safeEmit({ type: EV.ERROR, path: dirPath, error });
       }
     }
   }
 
-  /**
-   * Safely stat a path, returning null if it doesn't exist
-   */
+  // ===========================================================================
+  // Health Check & Auto-Restart
+  // ===========================================================================
+
+  private startHealthCheck(): void {
+    console.log('[smartwatch] Starting health check (every 30s)');
+    this.healthCheckInterval = setInterval(async () => {
+      console.log(`[smartwatch] Health check: ${this.watchers.size} watchers active`);
+
+      for (const [basePath] of this.watchers) {
+        try {
+          const stats = await fs.promises.stat(basePath);
+          const currentInode = BigInt(stats.ino);
+          const previousInode = this.watchedInodes.get(basePath);
+
+          if (previousInode !== undefined && currentInode !== previousInode) {
+            console.warn(`[smartwatch] Inode changed for ${basePath}: ${previousInode} -> ${currentInode}`);
+            console.warn('[smartwatch] fs.watch watches inode, not path - restarting watcher');
+            this.restartWatcher(basePath, new Error('Inode changed - directory was replaced'));
+          }
+        } catch (error: any) {
+          if (error.code === 'ENOENT') {
+            console.error(`[smartwatch] Health check failed: ${basePath} no longer exists`);
+            this.restartWatcher(basePath, new Error('Watched path disappeared'));
+          } else if (error.code === 'ENOSPC') {
+            console.error('[smartwatch] ENOSPC: inotify watch limit exceeded!');
+            console.error('[smartwatch] Fix: echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p');
+            this.safeEmit({ type: EV.ERROR, path: basePath, error });
+            // Trigger restart - watcher may be broken after ENOSPC
+            this.restartWatcher(basePath, error);
+          } else {
+            console.error(`[smartwatch] Health check error for ${basePath}:`, error);
+          }
+        }
+      }
+    }, CONFIG.HEALTH_CHECK_INTERVAL);
+  }
+
+  private stopHealthCheck(): void {
+    if (this.healthCheckInterval) {
+      clearInterval(this.healthCheckInterval);
+      this.healthCheckInterval = null;
+      console.log('[smartwatch] Stopped health check');
+    }
+  }
+
+  private async restartWatcher(basePath: string, error: Error): Promise<void> {
+    // Guard against concurrent restarts
+    if (this.restartingPaths.has(basePath)) {
+      console.log(`[smartwatch] Restart already in progress for ${basePath}, skipping`);
+      return;
+    }
+    this.restartingPaths.add(basePath);
+
+    try {
+      const attempts = (this.restartAttempts.get(basePath) || 0) + 1;
+      this.restartAttempts.set(basePath, attempts);
+
+      console.log(`[smartwatch] Watcher error for ${basePath}: ${error.message}`);
+      console.log(`[smartwatch] Restart attempt ${attempts}/${CONFIG.MAX_RETRIES}`);
+
+      if (attempts > CONFIG.MAX_RETRIES) {
+        console.error(`[smartwatch] Max retries exceeded for ${basePath}, giving up`);
+        this.safeEmit({
+          type: EV.ERROR,
+          path: basePath,
+          error: new Error(`Max restart retries (${CONFIG.MAX_RETRIES}) exceeded`),
+        });
+        return;
+      }
+
+      // Close old watcher
+      const oldWatcher = this.watchers.get(basePath);
+      if (oldWatcher) {
+        try { oldWatcher.close(); } catch {}
+        this.watchers.delete(basePath);
+      }
+
+      // Clear pending unlinks for this base path (prevent stale events)
+      for (const [unlinkedPath, pending] of this.pendingUnlinks) {
+        if (unlinkedPath.startsWith(basePath)) {
+          clearTimeout(pending.timeout);
+          this.pendingUnlinks.delete(unlinkedPath);
+        }
+      }
+
+      // Clear stale DirEntry data (will be repopulated by rescan)
+      for (const [dirPath, entry] of this.watched) {
+        if (dirPath === basePath || dirPath.startsWith(basePath + path.sep)) {
+          entry.dispose();
+          this.watched.delete(dirPath);
+        }
+      }
+
+      // Exponential backoff with abort support
+      const delay = this.restartDelays.get(basePath) || CONFIG.INITIAL_RESTART_DELAY;
+      console.log(`[smartwatch] Waiting ${delay}ms before restart...`);
+
+      const abortController = new AbortController();
+      this.restartAbortControllers.set(basePath, abortController);
+
+      try {
+        await new Promise<void>((resolve, reject) => {
+          const timeout = setTimeout(resolve, delay);
+          abortController.signal.addEventListener('abort', () => {
+            clearTimeout(timeout);
+            reject(new Error('Restart aborted by stop()'));
+          });
+        });
+      } catch {
+        console.log(`[smartwatch] Restart aborted for ${basePath}`);
+        return;
+      } finally {
+        this.restartAbortControllers.delete(basePath);
+      }
+
+      if (!this._isWatching) {
+        console.log('[smartwatch] Watcher stopped during restart delay, aborting');
+        return;
+      }
+
+      this.restartDelays.set(basePath, Math.min(delay * 2, CONFIG.MAX_RESTART_DELAY));
+
+      try {
+        await this.watchPath(basePath);
+        // Rescan to catch files created during restart window
+        await this.scanDirectory(basePath, 0);
+        console.log(`[smartwatch] Successfully restarted watcher for ${basePath}`);
+        this.restartDelays.set(basePath, CONFIG.INITIAL_RESTART_DELAY);
+        this.restartAttempts.set(basePath, 0);
+      } catch (restartError) {
+        console.error(`[smartwatch] Restart failed for ${basePath}:`, restartError);
+        this.restartingPaths.delete(basePath);
+        this.restartWatcher(basePath, restartError as Error);
+        return;
+      }
+    } finally {
+      this.restartingPaths.delete(basePath);
+    }
+  }
+
+  // ===========================================================================
+  // Utilities
+  // ===========================================================================
+
   private async statSafe(filePath: string): Promise<fs.Stats | null> {
     try {
-      if (this.options.followSymlinks) {
-        return await fs.promises.stat(filePath);
-      } else {
-        return await fs.promises.lstat(filePath);
+      return await (this.options.followSymlinks
+        ? fs.promises.stat(filePath)
+        : fs.promises.lstat(filePath));
+    } catch (error: any) {
+      if (error.code === 'ENOENT' || error.code === 'ENOTDIR') {
+        return null;
       }
-    } catch {
+      console.warn(`[smartwatch] statSafe warning for ${filePath}: ${error.code} - ${error.message}`);
       return null;
     }
   }
 
-  /**
-   * Check if a path was known to be a directory (for proper unlink event type)
-   */
   private isKnownDirectory(filePath: string): boolean {
-    // Check if any watched files are children of this path
-    for (const watched of this.watchedFiles) {
-      if (watched.startsWith(filePath + path.sep)) {
-        return true;
-      }
-    }
-    return false;
+    const resolved = path.resolve(filePath);
+    return this.watched.has(resolved);
   }
 }