Remove backup expectations (#2209)

Author: davidmorgan

pkgs/watcher/test/directory_watcher/file_tests.dart

@@ -12,6 +12,12 @@ import 'package:watcher/src/utils.dart';
 import '../utils.dart';
 
 void fileTests() {
+  for (var i = 0; i != runsPerTest; ++i) {
+    _fileTests();
+  }
+}
+
+void _fileTests() {
   test('does not notify for files that already exist when started', () async {
     // Make some pre-existing files.
     writeFile('a.txt');
@@ -141,27 +147,13 @@ void fileTests() {
     });
   });
 
-  // Most of the time, when multiple filesystem actions happen in sequence,
-  // they'll be batched together and the watcher will see them all at once.
-  // These tests verify that the watcher normalizes and combine these events
-  // properly. However, very occasionally the events will be reported in
-  // separate batches, and the watcher will report them as though they occurred
-  // far apart in time, so each of these tests has a "backup case" to allow for
-  // that as well.
   group('clustered changes', () {
     test("doesn't notify when a file is created and then immediately removed",
         () async {
       writeFile('test.txt');
       await startWatcher();
       writeFile('file.txt');
       deleteFile('file.txt');
-
-      // Backup case.
-      startClosingEventStream();
-      await allowEvents(() {
-        expectAddEvent('file.txt');
-        expectRemoveEvent('file.txt');
-      });
     });
 
     test(
@@ -173,13 +165,7 @@ void fileTests() {
       deleteFile('file.txt');
       writeFile('file.txt', contents: 're-created');
 
-      await allowEither(() {
-        expectModifyEvent('file.txt');
-      }, () {
-        // Backup case.
-        expectRemoveEvent('file.txt');
-        expectAddEvent('file.txt');
-      });
+      await expectModifyEvent('file.txt');
     });
 
     test(
@@ -191,14 +177,7 @@ void fileTests() {
       renameFile('old.txt', 'new.txt');
       writeFile('old.txt', contents: 're-created');
 
-      await allowEither(() {
-        inAnyOrder([isModifyEvent('old.txt'), isAddEvent('new.txt')]);
-      }, () {
-        // Backup case.
-        expectRemoveEvent('old.txt');
-        expectAddEvent('new.txt');
-        expectAddEvent('old.txt');
-      });
+      await inAnyOrder([isModifyEvent('old.txt'), isAddEvent('new.txt')]);
     });
 
     test(
@@ -210,9 +189,6 @@ void fileTests() {
       writeFile('file.txt', contents: 'modified');
       deleteFile('file.txt');
 
-      // Backup case.
-      await allowModifyEvent('file.txt');
-
       await expectRemoveEvent('file.txt');
     });
 
@@ -224,10 +200,6 @@ void fileTests() {
       writeFile('file.txt', contents: 'modified');
 
       await expectAddEvent('file.txt');
-
-      // Backup case.
-      startClosingEventStream();
-      await allowModifyEvent('file.txt');
     });
   });
 

pkgs/watcher/test/directory_watcher/link_tests.dart

@@ -9,6 +9,12 @@ import 'package:test/test.dart';
 import '../utils.dart';
 
 void linkTests({required bool isNative}) {
+  for (var i = 0; i != runsPerTest; ++i) {
+    _linkTests(isNative: isNative);
+  }
+}
+
+void _linkTests({required bool isNative}) {
   test('notifies when a link is added', () async {
     createDir('targets');
     createDir('links');

pkgs/watcher/test/directory_watcher/linux_test.dart

@@ -32,15 +32,9 @@ void main() {
     renameDir('dir/sub', 'sub');
     renameDir('sub', 'dir/sub');
 
-    await allowEither(() {
-      inAnyOrder(withPermutations(
-          (i, j, k) => isRemoveEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-
-      inAnyOrder(withPermutations(
-          (i, j, k) => isAddEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-    }, () {
-      inAnyOrder(withPermutations(
-          (i, j, k) => isModifyEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-    });
+    await inAnyOrder(withPermutations(
+        (i, j, k) => isRemoveEvent('dir/sub/sub-$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

@@ -46,16 +46,10 @@ void main() {
     renameDir('dir/sub', 'sub');
     renameDir('sub', 'dir/sub');
 
-    await allowEither(() {
-      inAnyOrder(withPermutations(
-          (i, j, k) => isRemoveEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-
-      inAnyOrder(withPermutations(
-          (i, j, k) => isAddEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-    }, () {
-      inAnyOrder(withPermutations(
-          (i, j, k) => isModifyEvent('dir/sub/sub-$i/sub-$j/file-$k.txt')));
-    });
+    await inAnyOrder(withPermutations(
+        (i, j, k) => isRemoveEvent('dir/sub/sub-$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

pkgs/watcher/test/file_watcher/file_tests.dart

@@ -13,11 +13,13 @@ void fileTests({required bool isNative}) {
     writeFile('file.txt');
   });
 
+  for (var i = 0; i != runsPerTest; ++i) {
+    _fileTests(isNative: isNative);
+  }
+}
+
+void _fileTests({required bool isNative}) {
   test("doesn't notify if the file isn't modified", () async {
-    // TODO(davidmorgan): fix startup race on MacOS.
-    if (isNative && Platform.isMacOS) {
-      await Future<void>.delayed(const Duration(milliseconds: 100));
-    }
     await startWatcher(path: 'file.txt');
     await expectNoEvents();
   });

pkgs/watcher/test/file_watcher/link_tests.dart

@@ -12,6 +12,12 @@ void linkTests({required bool isNative}) {
     writeLink(link: 'link.txt', target: 'target.txt');
   });
 
+  for (var i = 0; i != runsPerTest; ++i) {
+    _linkTests(isNative: isNative);
+  }
+}
+
+void _linkTests({required bool isNative}) {
   test("doesn't notify if nothing is modified", () async {
     await startWatcher(path: 'link.txt');
     await expectNoEvents();

pkgs/watcher/test/utils.dart

@@ -12,6 +12,9 @@ import 'package:test_descriptor/test_descriptor.dart' as d;
 import 'package:watcher/src/stat.dart';
 import 'package:watcher/watcher.dart';
 
+/// Edit this to run fast-running tests many times.
+int runsPerTest = 1;
+
 typedef WatcherFactory = Watcher Function(String directory);
 
 /// Sets the function used to create the watcher.
@@ -164,62 +167,18 @@ void startClosingEventStream() async {
   await _watcherEvents.cancel(immediate: true);
 }
 
-/// A list of [StreamMatcher]s that have been collected using
-/// [_collectStreamMatcher].
-List<StreamMatcher>? _collectedStreamMatchers;
-
-/// Collects all stream matchers that are registered within [block] into a
-/// single stream matcher.
-///
-/// The returned matcher will match each of the collected matchers in order.
-StreamMatcher _collectStreamMatcher(void Function() block) {
-  var oldStreamMatchers = _collectedStreamMatchers;
-  var collectedStreamMatchers = _collectedStreamMatchers = <StreamMatcher>[];
-  try {
-    block();
-    return emitsInOrder(collectedStreamMatchers);
-  } finally {
-    _collectedStreamMatchers = oldStreamMatchers;
-  }
-}
-
-/// Either add [streamMatcher] as an expectation to [_watcherEvents], or collect
-/// it with [_collectStreamMatcher].
+/// Add [streamMatcher] as an expectation to [_watcherEvents].
 ///
 /// [streamMatcher] can be a [StreamMatcher], a [Matcher], or a value.
-Future _expectOrCollect(Matcher streamMatcher) {
-  var collectedStreamMatchers = _collectedStreamMatchers;
-  if (collectedStreamMatchers != null) {
-    collectedStreamMatchers.add(emits(streamMatcher));
-    return Future.sync(() {});
-  } else {
-    return expectLater(_watcherEvents, emits(streamMatcher));
-  }
+Future _expect(Matcher streamMatcher) {
+  return expectLater(_watcherEvents, emits(streamMatcher));
 }
 
 /// Expects that [matchers] will match emitted events in any order.
 ///
 /// [matchers] may be [Matcher]s or values, but not [StreamMatcher]s.
-Future inAnyOrder(Iterable matchers) {
-  matchers = matchers.toSet();
-  return _expectOrCollect(emitsInAnyOrder(matchers));
-}
-
-/// Expects that the expectations established in either [block1] or [block2]
-/// will match the emitted events.
-///
-/// If both blocks match, the one that consumed more events will be used.
-Future allowEither(void Function() block1, void Function() block2) =>
-    _expectOrCollect(emitsAnyOf(
-        [_collectStreamMatcher(block1), _collectStreamMatcher(block2)]));
-
-/// Allows the expectations established in [block] to match the emitted events.
-///
-/// If the expectations in [block] don't match, no error will be raised and no
-/// events will be consumed. If this is used at the end of a test,
-/// [startClosingEventStream] should be called before it.
-Future allowEvents(void Function() block) =>
-    _expectOrCollect(mayEmit(_collectStreamMatcher(block)));
+Future inAnyOrder(Iterable matchers) =>
+    _expect(emitsInAnyOrder(matchers.toSet()));
 
 /// Returns a StreamMatcher that matches a [WatchEvent] with the given [type]
 /// and [path].
@@ -274,24 +233,16 @@ Future<List<WatchEvent>> takeEvents({required Duration duration}) async {
 
 /// Expects that the next event emitted will be for an add event for [path].
 Future expectAddEvent(String path) =>
-    _expectOrCollect(isWatchEvent(ChangeType.ADD, path));
+    _expect(isWatchEvent(ChangeType.ADD, path));
 
 /// Expects that the next event emitted will be for a modification event for
 /// [path].
 Future expectModifyEvent(String path) =>
-    _expectOrCollect(isWatchEvent(ChangeType.MODIFY, path));
+    _expect(isWatchEvent(ChangeType.MODIFY, path));
 
 /// Expects that the next event emitted will be for a removal event for [path].
 Future expectRemoveEvent(String path) =>
-    _expectOrCollect(isWatchEvent(ChangeType.REMOVE, path));
-
-/// Consumes a modification event for [path] if one is emitted at this point in
-/// the schedule, but doesn't throw an error if it isn't.
-///
-/// If this is used at the end of a test, [startClosingEventStream] should be
-/// called before it.
-Future allowModifyEvent(String path) =>
-    _expectOrCollect(mayEmit(isWatchEvent(ChangeType.MODIFY, path)));
+    _expect(isWatchEvent(ChangeType.REMOVE, path));
 
 /// Track a fake timestamp to be used when writing files. This always increases
 /// so that files that are deleted and re-created do not have their timestamp