Update KeepAlive.debugTypicalAncestorWidgetClass (flutter#133498)

Author: Piinks

packages/flutter/lib/src/cupertino/dialog.dart

@@ -1577,8 +1577,7 @@ class _ActionButtonParentDataWidget
   }
 
   @override
-  Type get debugTypicalAncestorWidgetClass =>
-      _CupertinoDialogActionsRenderWidget;
+  Type get debugTypicalAncestorWidgetClass => _CupertinoDialogActionsRenderWidget;
 }
 
 // ParentData applied to individual action buttons that report whether or not

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

@@ -1592,15 +1592,19 @@ abstract class ParentDataWidget<T extends ParentData> extends ProxyWidget {
     return renderObject.parentData is T;
   }
 
-  /// The [RenderObjectWidget] that is typically used to set up the [ParentData]
-  /// that [applyParentData] will write to.
+  /// Describes the [RenderObjectWidget] that is typically used to set up the
+  /// [ParentData] that [applyParentData] will write to.
   ///
   /// This is only used in error messages to tell users what widget typically
-  /// wraps this [ParentDataWidget].
+  /// wraps this [ParentDataWidget] through
+  /// [debugTypicalAncestorWidgetDescription].
   ///
   /// ## Implementations
   ///
-  /// The returned type should be a subclass of `RenderObjectWidget`.
+  /// The returned Type should describe a subclass of `RenderObjectWidget`. If
+  /// more than one Type is supported, use
+  /// [debugTypicalAncestorWidgetDescription], which typically inserts this
+  /// value but can be overridden to describe more than one Type.
   ///
   /// ```dart
   ///   @override
@@ -1612,6 +1616,16 @@ abstract class ParentDataWidget<T extends ParentData> extends ProxyWidget {
   /// type is specialized), or specifying the upper bound (e.g. `Foo<Object?>`).
   Type get debugTypicalAncestorWidgetClass;
 
+  /// Describes the [RenderObjectWidget] that is typically used to set up the
+  /// [ParentData] that [applyParentData] will write to.
+  ///
+  /// This is only used in error messages to tell users what widget typically
+  /// wraps this [ParentDataWidget].
+  ///
+  /// Returns [debugTypicalAncestorWidgetClass] by default as a String. This can
+  /// be overridden to describe more than one Type of valid parent.
+  String get debugTypicalAncestorWidgetDescription => '$debugTypicalAncestorWidgetClass';
+
   Iterable<DiagnosticsNode> _debugDescribeIncorrectParentDataType({
     required ParentData? parentData,
     RenderObjectWidget? parentDataCreator,
@@ -1632,7 +1646,7 @@ abstract class ParentDataWidget<T extends ParentData> extends ProxyWidget {
         ),
       ErrorHint(
         'Usually, this means that the $runtimeType widget has the wrong ancestor RenderObjectWidget. '
-        'Typically, $runtimeType widgets are placed directly inside $debugTypicalAncestorWidgetClass widgets.',
+        'Typically, $runtimeType widgets are placed directly inside $debugTypicalAncestorWidgetDescription widgets.',
       ),
       if (parentDataCreator != null)
         ErrorHint(
@@ -6300,7 +6314,7 @@ abstract class RenderObjectElement extends Element {
             ErrorSummary('Incorrect use of ParentDataWidget.'),
             ErrorDescription('The following ParentDataWidgets are providing parent data to the same RenderObject:'),
             for (final ParentDataElement<ParentData> ancestor in badAncestors)
-              ErrorDescription('- ${ancestor.widget} (typically placed directly inside a ${(ancestor.widget as ParentDataWidget<ParentData>).debugTypicalAncestorWidgetClass} widget)'),
+              ErrorDescription('- ${ancestor.widget} (typically placed directly inside a ${(ancestor.widget as ParentDataWidget<ParentData>).debugTypicalAncestorWidgetDescription} widget)'),
             ErrorDescription('However, a RenderObject can only receive parent data from at most one ParentDataWidget.'),
             ErrorHint('Usually, this indicates that at least one of the offending ParentDataWidgets listed above is not placed directly inside a compatible ancestor widget.'),
             ErrorDescription('The ownership chain for the RenderObject that received the parent data was:\n  ${debugGetCreatorChain(10)}'),

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

@@ -1311,8 +1311,8 @@ class _SliverOffstageElement extends SingleChildRenderObjectElement {
 /// Mark a child as needing to stay alive even when it's in a lazy list that
 /// would otherwise remove it.
 ///
-/// This widget is for use in [SliverWithKeepAliveWidget]s, such as
-/// [SliverGrid] or [SliverList].
+/// This widget is for use in a [RenderAbstractViewport]s, such as
+/// [Viewport] or [TwoDimensionalViewport].
 ///
 /// This widget is rarely used directly. The [SliverChildBuilderDelegate] and
 /// [SliverChildListDelegate] delegates, used with [SliverList] and
@@ -1322,6 +1322,9 @@ class _SliverOffstageElement extends SingleChildRenderObjectElement {
 /// each child, causing [KeepAlive] widgets to be automatically added and
 /// configured in response to [KeepAliveNotification]s.
 ///
+/// The same `addAutomaticKeepAlives` feature is supported by the
+/// [TwoDimensionalChildBuilderDelegate] and [TwoDimensionalChildListDelegate].
+///
 /// Therefore, to keep a widget alive, it is more common to use those
 /// notifications than to directly deal with [KeepAlive] widgets.
 ///
@@ -1365,7 +1368,10 @@ class KeepAlive extends ParentDataWidget<KeepAliveParentDataMixin> {
   bool debugCanApplyOutOfTurn() => keepAlive;
 
   @override
-  Type get debugTypicalAncestorWidgetClass => SliverWithKeepAliveWidget;
+  Type get debugTypicalAncestorWidgetClass => throw FlutterError('Multiple Types are supported, use debugTypicalAncestorWidgetDescription.');
+
+  @override
+  String get debugTypicalAncestorWidgetDescription => 'SliverWithKeepAliveWidget or TwoDimensionalViewport';
 
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {

packages/flutter/test/widgets/keep_alive_test.dart

@@ -47,6 +47,14 @@ List<Widget> generateList(Widget child) {
 }
 
 void main() {
+  test('KeepAlive debugTypicalAncestorWidgetClass', () {
+    final KeepAlive keepAlive = KeepAlive(keepAlive: false, child: Container());
+    expect(
+      keepAlive.debugTypicalAncestorWidgetDescription,
+      'SliverWithKeepAliveWidget or TwoDimensionalViewport',
+    );
+  });
+
   testWidgetsWithLeakTracking('KeepAlive with ListView with itemExtent', (WidgetTester tester) async {
     await tester.pumpWidget(
       Directionality(