Unify watcher tests.

Author: davidmorgan

pkgs/watcher/lib/src/directory_watcher/polling.dart

@@ -160,13 +160,19 @@ class _PollingDirectoryWatcher
 
     if (_events.isClosed) return;
 
-    _lastModifieds[file] = modified;
     _polledFiles.add(file);
+    if (modified == null) {
+      // The file was in the directory listing but has been removed since then.
+      // Don't add to _lastModifieds, it will be reported as a REMOVE.
+      return;
+    }
+    _lastModifieds[file] = modified;
 
     // Only notify if we're ready to emit events.
     if (!isReady) return;
 
     var type = lastModified == null ? ChangeType.ADD : ChangeType.MODIFY;
+
     _events.add(WatchEvent(type, file));
   }
 

pkgs/watcher/test/directory_watcher/file_tests.dart

@@ -11,7 +11,7 @@ import 'package:watcher/src/utils.dart';
 
 import '../utils.dart';
 
-void fileTests() {
+void fileTests({required bool isNative}) {
   test('does not notify for files that already exist when started', () async {
     // Make some pre-existing files.
     writeFile('a.txt');
@@ -291,6 +291,29 @@ void fileTests() {
       })));
     });
 
+    test(
+        'emits events for many nested files moved out then immediately back in',
+        () async {
+      withPermutations(
+          (i, j, k) => writeFile('dir/sub/sub-$i/sub-$j/file-$k.txt'));
+
+      await startWatcher(path: 'dir');
+
+      renameDir('dir/sub', 'sub');
+      renameDir('sub', 'dir/sub');
+
+      if (isNative) {
+        await inAnyOrder(withPermutations(
+            (i, j, k) => isRemoveEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
+        await inAnyOrder(withPermutations(
+            (i, j, k) => isAddEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
+      } else {
+        // Polling watchers can't detect this as directory contents mtimes
+        // aren't updated.
+        await expectNoEvents();
+      }
+    });
+
     test(
         'emits events for many files added at once in a subdirectory with the '
         'same name as a removed file', () async {

pkgs/watcher/test/directory_watcher/linux_test.dart

@@ -16,25 +16,10 @@ import 'link_tests.dart';
 void main() {
   watcherFactory = LinuxDirectoryWatcher.new;
 
-  fileTests();
+  fileTests(isNative: true);
   linkTests(isNative: true);
 
   test('DirectoryWatcher creates a LinuxDirectoryWatcher on Linux', () {
     expect(DirectoryWatcher('.'), const TypeMatcher<LinuxDirectoryWatcher>());
   });
-
-  test('emits events for many nested files moved out then immediately back in',
-      () async {
-    withPermutations(
-        (i, j, k) => writeFile('dir/sub/sub-$i/sub-$j/file-$k.txt'));
-    await startWatcher(path: 'dir');
-
-    renameDir('dir/sub', 'sub');
-    renameDir('sub', 'dir/sub');
-
-    await inAnyOrder(withPermutations(
-        (i, j, k) => isRemoveEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-    await inAnyOrder(withPermutations(
-        (i, j, k) => isAddEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-  });
 }

pkgs/watcher/test/directory_watcher/mac_os_test.dart

@@ -16,7 +16,7 @@ import 'link_tests.dart';
 void main() {
   watcherFactory = MacOSDirectoryWatcher.new;
 
-  fileTests();
+  fileTests(isNative: true);
   linkTests(isNative: true);
 
   test('DirectoryWatcher creates a MacOSDirectoryWatcher on Mac OS', () {
@@ -36,21 +36,6 @@ void main() {
     await expectAddEvent('dir/newer.txt');
   });
 
-  test('emits events for many nested files moved out then immediately back in',
-      () async {
-    withPermutations(
-        (i, j, k) => writeFile('dir/sub/sub-$i/sub-$j/file-$k.txt'));
-
-    await startWatcher(path: 'dir');
-
-    renameDir('dir/sub', 'sub');
-    renameDir('sub', 'dir/sub');
-
-    await inAnyOrder(withPermutations(
-        (i, j, k) => isRemoveEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-    await inAnyOrder(withPermutations(
-        (i, j, k) => isAddEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-  });
   test('does not suppress files with the same prefix as a directory', () async {
     // Regression test for https://github.com/dart-lang/watcher/issues/83
     writeFile('some_name.txt');

pkgs/watcher/test/directory_watcher/polling_test.dart

@@ -21,7 +21,7 @@ void main() {
   group('with mock mtime', () {
     setUp(enableMockModificationTimes);
 
-    fileTests();
+    fileTests(isNative: false);
     linkTests(isNative: false);
 
     test('does not notify if the modification time did not change', () async {
@@ -38,7 +38,7 @@ void main() {
   group('with real mtime', () {
     setUp(enableWaitingForDifferentModificationTimes);
 
-    fileTests();
+    fileTests(isNative: false);
     linkTests(isNative: false);
   });
 }

pkgs/watcher/test/directory_watcher/windows_test.dart

@@ -21,7 +21,7 @@ import 'link_tests.dart';
 void main() {
   watcherFactory = WindowsDirectoryWatcher.new;
 
-  fileTests();
+  fileTests(isNative: true);
   linkTests(isNative: true);
 
   test('DirectoryWatcher creates a WindowsDirectoryWatcher on Windows', () {

pkgs/watcher/test/utils.dart

@@ -393,7 +393,9 @@ void renameDir(String from, String to) {
     final knownFilePaths = mockFileModificationTimes.keys.toList();
     for (final filePath in knownFilePaths) {
       if (p.isWithin(from, filePath)) {
-        mockFileModificationTimes[filePath.replaceAll(from, to)] =
+        final movedPath = '$to/${filePath.substring(from.length + 1)}';
+        print('$filePath -> $movedPath');
+        mockFileModificationTimes[movedPath] =
             mockFileModificationTimes[filePath]!;
         mockFileModificationTimes.remove(filePath);
       }