Made flag for debugging build time of user created widgets (#100926)

* Added a bool that allows us to limit debugProfileBuildsEnabled to user
created widgets.

* made it turned on by default

* switched to hashmap

* Cleaned everything up and added tests

* fixed an odd test where it wants to be able to add asserts and run in profile mode

* hixie feedback

* hixie2

* made it default to false

* updated docstring as per dans request

Author: gaaclarke

dev/tracing_tests/test/timeline_test.dart

@@ -110,6 +110,17 @@ void main() {
     expect(args['color'], 'Color(0xffffffff)');
     debugProfileBuildsEnabled = false;
 
+    debugProfileBuildsEnabledUserWidgets = true;
+    await runFrame(() { TestRoot.state.updateWidget(Placeholder(key: UniqueKey(), color: const Color(0xFFFFFFFF))); });
+    events = await fetchInterestingEvents(interestingLabels);
+    expect(
+      events.map<String>(eventToName),
+      <String>['BUILD', 'Placeholder', 'LAYOUT', 'UPDATING COMPOSITING BITS', 'PAINT', 'COMPOSITING', 'FINALIZE TREE'],
+    );
+    args = (events.where((TimelineEvent event) => event.json!['name'] == '$Placeholder').single.json!['args'] as Map<String, Object?>).cast<String, String>();
+    expect(args['color'], 'Color(0xffffffff)');
+    debugProfileBuildsEnabledUserWidgets = false;
+
     debugProfileLayoutsEnabled = true;
     await runFrame(() { TestRoot.state.updateWidget(Placeholder(key: UniqueKey())); });
     events = await fetchInterestingEvents(interestingLabels);

packages/flutter/lib/src/widgets/debug.dart

@@ -114,8 +114,24 @@ bool debugPrintGlobalKeyedWidgetLifecycle = false;
 ///  * [debugProfileLayoutsEnabled], which does something similar for layout,
 ///    and [debugPrintLayouts], its console equivalent.
 ///  * [debugProfilePaintsEnabled], which does something similar for painting.
+///  * [debugProfileBuildsEnabledUserWidgets], which adds events for user-created
+///    [Widget] build times and incurs less overhead.
 bool debugProfileBuildsEnabled = false;
 
+/// Adds [Timeline] events for every user-created [Widget] built.
+///
+/// A user-created [Widget] is any [Widget] that is constructed in the root
+/// library. Often [Widget]s contain child [Widget]s that are constructed in
+/// libraries (for example, a [TextButton] having a [RichText] child). Timeline
+/// events for those children will be omitted with this flag. This works for any
+/// [Widget] not just ones declared in the root library.
+///
+/// See also:
+///
+///  * [debugProfileBuildsEnabled], which functions similarly but shows events
+///    for every widget and has a higher overhead cost.
+bool debugProfileBuildsEnabledUserWidgets = false;
+
 /// Show banners for deprecated widgets.
 bool debugHighlightDeprecatedWidgets = false;
 
@@ -423,7 +439,8 @@ bool debugAssertAllWidgetVarsUnset(String reason) {
         debugPrintScheduleBuildForStacks ||
         debugPrintGlobalKeyedWidgetLifecycle ||
         debugProfileBuildsEnabled ||
-        debugHighlightDeprecatedWidgets) {
+        debugHighlightDeprecatedWidgets ||
+        debugProfileBuildsEnabledUserWidgets) {
       throw FlutterError(reason);
     }
     return true;

packages/flutter/lib/src/widgets/framework.dart

@@ -14,6 +14,7 @@ import 'debug.dart';
 import 'focus_manager.dart';
 import 'inherited_model.dart';
 import 'notification_listener.dart';
+import 'widget_inspector.dart';
 
 export 'package:flutter/foundation.dart' show
   factory,
@@ -2640,10 +2641,13 @@ class BuildOwner {
           }
           return true;
         }());
-        if (!kReleaseMode && debugProfileBuildsEnabled) {
+        final bool isTimelineTracked = !kReleaseMode && _isProfileBuildsEnabledFor(element.widget);
+        if (isTimelineTracked) {
           Map<String, String> debugTimelineArguments = timelineArgumentsIndicatingLandmarkEvent;
           assert(() {
-            debugTimelineArguments = element.widget.toDiagnosticsNode().toTimelineArguments();
+            if (kDebugMode) {
+              debugTimelineArguments = element.widget.toDiagnosticsNode().toTimelineArguments();
+            }
             return true;
           }());
           Timeline.startSync(
@@ -2668,7 +2672,7 @@ class BuildOwner {
             ],
           );
         }
-        if (!kReleaseMode && debugProfileBuildsEnabled)
+        if (isTimelineTracked)
           Timeline.finishSync();
         index += 1;
         if (dirtyCount < _dirtyElements.length || _dirtyElementsNeedsResorting!) {
@@ -3078,6 +3082,12 @@ class _NotificationNode {
   }
 }
 
+bool _isProfileBuildsEnabledFor(Widget widget) {
+  return debugProfileBuildsEnabled ||
+      (debugProfileBuildsEnabledUserWidgets &&
+          debugIsWidgetLocalCreation(widget));
+}
+
 /// An instantiation of a [Widget] at a particular location in the tree.
 ///
 /// Widgets describe how to configure a subtree but the same widget can be used
@@ -3503,10 +3513,13 @@ abstract class Element extends DiagnosticableTree implements BuildContext {
       } else if (hasSameSuperclass && Widget.canUpdate(child.widget, newWidget)) {
         if (child.slot != newSlot)
           updateSlotForChild(child, newSlot);
-        if (!kReleaseMode && debugProfileBuildsEnabled) {
+        final bool isTimelineTracked = !kReleaseMode && _isProfileBuildsEnabledFor(newWidget);
+        if (isTimelineTracked) {
           Map<String, String> debugTimelineArguments = timelineArgumentsIndicatingLandmarkEvent;
           assert(() {
-            debugTimelineArguments = newWidget.toDiagnosticsNode().toTimelineArguments();
+            if (kDebugMode) {
+              debugTimelineArguments = newWidget.toDiagnosticsNode().toTimelineArguments();
+            }
             return true;
           }());
           Timeline.startSync(
@@ -3515,7 +3528,7 @@ abstract class Element extends DiagnosticableTree implements BuildContext {
           );
         }
         child.update(newWidget);
-        if (!kReleaseMode && debugProfileBuildsEnabled)
+        if (isTimelineTracked)
           Timeline.finishSync();
         assert(child.widget == newWidget);
         assert(() {
@@ -3765,10 +3778,13 @@ abstract class Element extends DiagnosticableTree implements BuildContext {
   Element inflateWidget(Widget newWidget, Object? newSlot) {
     assert(newWidget != null);
 
-    if (!kReleaseMode && debugProfileBuildsEnabled) {
+    final bool isTimelineTracked = !kReleaseMode && _isProfileBuildsEnabledFor(newWidget);
+    if (isTimelineTracked) {
       Map<String, String> debugTimelineArguments = timelineArgumentsIndicatingLandmarkEvent;
       assert(() {
-        debugTimelineArguments = newWidget.toDiagnosticsNode().toTimelineArguments();
+        if (kDebugMode) {
+          debugTimelineArguments = newWidget.toDiagnosticsNode().toTimelineArguments();
+        }
         return true;
       }());
       Timeline.startSync(
@@ -3800,7 +3816,7 @@ abstract class Element extends DiagnosticableTree implements BuildContext {
     newChild.mount(this, newSlot);
     assert(newChild._lifecycleState == _ElementLifecycle.active);
 
-    if (!kReleaseMode && debugProfileBuildsEnabled)
+    if (isTimelineTracked)
       Timeline.finishSync();
 
     return newChild;

packages/flutter/lib/src/widgets/widget_inspector.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'dart:async';
+import 'dart:collection' show HashMap;
 import 'dart:convert';
 import 'dart:developer' as developer;
 import 'dart:math' as math;
@@ -742,6 +743,8 @@ mixin WidgetInspectorService {
   int _nextId = 0;
 
   List<String>? _pubRootDirectories;
+  /// Memoization for [_isLocalCreationLocation].
+  final HashMap<String, bool> _isLocalCreationCache = HashMap<String, bool>();
 
   bool _trackRebuildDirtyWidgets = false;
   bool _trackRepaintWidgets = false;
@@ -1345,6 +1348,7 @@ mixin WidgetInspectorService {
     _pubRootDirectories = pubRootDirectories
       .map<String>((String directory) => Uri.parse(directory).path)
       .toList();
+    _isLocalCreationCache.clear();
   }
 
   /// Set the [WidgetInspector] selection to the object matching the specified
@@ -1518,14 +1522,11 @@ mixin WidgetInspectorService {
     if (creationLocation == null) {
       return false;
     }
-    return _isLocalCreationLocation(creationLocation);
+    return _isLocalCreationLocation(creationLocation.file);
   }
 
-  bool _isLocalCreationLocation(_Location? location) {
-    if (location == null) {
-      return false;
-    }
-    final String file = Uri.parse(location.file).path;
+  bool _isLocalCreationLocationImpl(String locationUri) {
+    final String file = Uri.parse(locationUri).path;
 
     // By default check whether the creation location was within package:flutter.
     if (_pubRootDirectories == null) {
@@ -1541,6 +1542,17 @@ mixin WidgetInspectorService {
     return false;
   }
 
+  /// Memoized version of [_isLocalCreationLocationImpl].
+  bool _isLocalCreationLocation(String locationUri) {
+    final bool? cachedValue = _isLocalCreationCache[locationUri];
+    if (cachedValue != null) {
+      return cachedValue;
+    }
+    final bool result = _isLocalCreationLocationImpl(locationUri);
+    _isLocalCreationCache[locationUri] = result;
+    return result;
+  }
+
   /// Wrapper around `json.encode` that uses a ring of cached values to prevent
   /// the Dart garbage collector from collecting objects between when
   /// the value is returned over the Observatory protocol and when the
@@ -2066,7 +2078,7 @@ class _ElementLocationStatsTracker {
       entry = _LocationCount(
         location: location,
         id: id,
-        local: WidgetInspectorService.instance._isLocalCreationLocation(location),
+        local: WidgetInspectorService.instance._isLocalCreationLocation(location.file),
       );
       if (entry.local) {
         newLocations.add(entry);
@@ -3072,14 +3084,24 @@ bool debugIsLocalCreationLocation(Object object) {
   bool isLocal = false;
   assert(() {
     final _Location? location = _getCreationLocation(object);
-    if (location == null)
-      isLocal =  false;
-    isLocal = WidgetInspectorService.instance._isLocalCreationLocation(location);
+    if (location != null) {
+      isLocal = WidgetInspectorService.instance._isLocalCreationLocation(location.file);
+    }
     return true;
   }());
   return isLocal;
 }
 
+/// Returns true if a [Widget] is user created.
+///
+/// This is a faster variant of `debugIsLocalCreationLocation` that is available
+/// in debug and profile builds but only works for [Widget].
+bool debugIsWidgetLocalCreation(Widget widget) {
+  final _Location? location = _getObjectCreationLocation(widget);
+  return location != null &&
+      WidgetInspectorService.instance._isLocalCreationLocation(location.file);
+}
+
 /// Returns the creation location of an object in String format if one is available.
 ///
 /// ex: "file:///path/to/main.dart:4:3"
@@ -3092,14 +3114,18 @@ String? _describeCreationLocation(Object object) {
   return location?.toString();
 }
 
+_Location? _getObjectCreationLocation(Object object) {
+  return object is _HasCreationLocation ? object._location : null;
+}
+
 /// Returns the creation location of an object if one is available.
 ///
 /// {@macro flutter.widgets.WidgetInspectorService.getChildrenSummaryTree}
 ///
 /// Currently creation locations are only available for [Widget] and [Element].
 _Location? _getCreationLocation(Object? object) {
-  final Object? candidate =  object is Element && !object.debugIsDefunct ? object.widget : object;
-  return candidate is _HasCreationLocation ? candidate._location : null;
+  final Object? candidate = object is Element && !object.debugIsDefunct ? object.widget : object;
+  return candidate == null ? null : _getObjectCreationLocation(candidate);
 }
 
 // _Location objects are always const so we don't need to worry about the GC
@@ -3226,7 +3252,7 @@ class InspectorSerializationDelegate implements DiagnosticsSerializationDelegate
     if (creationLocation != null) {
       result['locationId'] = _toLocationId(creationLocation);
       result['creationLocation'] = creationLocation.toJsonMap();
-      if (service._isLocalCreationLocation(creationLocation)) {
+      if (service._isLocalCreationLocation(creationLocation.file)) {
         _nodesCreatedByLocalProject.add(node);
         result['createdByLocalProject'] = true;
       }

packages/flutter/test/widgets/widget_inspector_test.dart

@@ -2998,6 +2998,46 @@ class _TestWidgetInspectorService extends TestWidgetInspectorService {
       expect(debugIsLocalCreationLocation(paddingElement.widget), isFalse);
     }, skip: !WidgetInspectorService.instance.isWidgetCreationTracked()); // [intended] Test requires --track-widget-creation flag.
 
+    testWidgets('debugIsWidgetLocalCreation test', (WidgetTester tester) async {
+      setupDefaultPubRootDirectory(service);
+
+      final GlobalKey key = GlobalKey();
+
+      await tester.pumpWidget(
+        Directionality(
+          textDirection: TextDirection.ltr,
+          child: Container(
+            padding: const EdgeInsets.all(8),
+            child: Text('target', key: key, textDirection: TextDirection.ltr),
+          ),
+        ),
+      );
+
+      final Element element = key.currentContext! as Element;
+      expect(debugIsWidgetLocalCreation(element.widget), isTrue);
+
+      final Finder paddingFinder = find.byType(Padding);
+      final Element paddingElement = paddingFinder.evaluate().first;
+      expect(debugIsWidgetLocalCreation(paddingElement.widget), isFalse);
+    }, skip: !WidgetInspectorService.instance.isWidgetCreationTracked()); // [intended] Test requires --track-widget-creation flag.
+
+    testWidgets('debugIsWidgetLocalCreation false test', (WidgetTester tester) async {
+      final GlobalKey key = GlobalKey();
+
+      await tester.pumpWidget(
+        Directionality(
+          textDirection: TextDirection.ltr,
+          child: Container(
+            padding: const EdgeInsets.all(8),
+            child: Text('target', key: key, textDirection: TextDirection.ltr),
+          ),
+        ),
+      );
+
+      final Element element = key.currentContext! as Element;
+      expect(debugIsWidgetLocalCreation(element.widget), isFalse);
+    }, skip: WidgetInspectorService.instance.isWidgetCreationTracked()); // [intended] Test requires --no-track-widget-creation flag.
+
     test('devToolsInspectorUri test', () {
       activeDevToolsServerAddress = 'http://127.0.0.1:9100';
       connectedVmServiceUri = 'http://127.0.0.1:55269/798ay5al_FM=/';

packages/flutter_tools/lib/src/build_system/targets/common.dart

@@ -222,7 +222,7 @@ class KernelSnapshot extends Target {
       ),
       aot: buildMode.isPrecompiled,
       buildMode: buildMode,
-      trackWidgetCreation: trackWidgetCreation && buildMode == BuildMode.debug,
+      trackWidgetCreation: trackWidgetCreation && buildMode != BuildMode.release,
       targetModel: targetModel,
       outputFilePath: environment.buildDir.childFile('app.dill').path,
       packagesPath: packagesFile.path,

packages/flutter_tools/test/general.shard/build_system/targets/common_test.dart

@@ -93,6 +93,7 @@ void main() {
         '--target=flutter',
         '--no-print-incremental-dependencies',
         ...buildModeOptions(BuildMode.profile, <String>[]),
+        '--track-widget-creation',
         '--aot',
         '--tfa',
         '--packages',
@@ -109,7 +110,7 @@ void main() {
     expect(processManager, hasNoRemainingExpectations);
   });
 
-  testWithoutContext('KernelSnapshot does not use track widget creation on profile builds', () async {
+  testWithoutContext('KernelSnapshot does use track widget creation on profile builds', () async {
     fileSystem.file('.dart_tool/package_config.json')
       ..createSync(recursive: true)
       ..writeAsStringSync('{"configVersion": 2, "packages":[]}');
@@ -129,6 +130,7 @@ void main() {
         '--target=flutter',
         '--no-print-incremental-dependencies',
         ...buildModeOptions(BuildMode.profile, <String>[]),
+        '--track-widget-creation',
         '--aot',
         '--tfa',
         '--packages',
@@ -166,6 +168,7 @@ void main() {
         '--target=flutter',
         '--no-print-incremental-dependencies',
         ...buildModeOptions(BuildMode.profile, <String>[]),
+        '--track-widget-creation',
         '--aot',
         '--tfa',
         '--packages',
@@ -204,6 +207,7 @@ void main() {
         '--target=flutter',
         '--no-print-incremental-dependencies',
         ...buildModeOptions(BuildMode.profile, <String>[]),
+        '--track-widget-creation',
         '--aot',
         '--tfa',
         '--packages',