Extract DiagnosticsNode serializer from WidgetInspector (#34012)

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

@@ -483,7 +483,7 @@ class CupertinoTextField extends StatefulWidget {
     properties.add(DiagnosticsProperty<bool>('expands', expands, defaultValue: false));
     properties.add(IntProperty('maxLength', maxLength, defaultValue: null));
     properties.add(FlagProperty('maxLengthEnforced', value: maxLengthEnforced, ifTrue: 'max length enforced'));
-    properties.add(DiagnosticsProperty<Color>('cursorColor', cursorColor, defaultValue: null));
+    properties.add(ColorProperty('cursorColor', cursorColor, defaultValue: null));
     properties.add(FlagProperty('selectionEnabled', value: selectionEnabled, defaultValue: true, ifFalse: 'selection disabled'));
     properties.add(DiagnosticsProperty<ScrollController>('scrollController', scrollController, defaultValue: null));
     properties.add(DiagnosticsProperty<ScrollPhysics>('scrollPhysics', scrollPhysics, defaultValue: null));

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

@@ -259,11 +259,11 @@ class CupertinoThemeData extends Diagnosticable {
     super.debugFillProperties(properties);
     const CupertinoThemeData defaultData = CupertinoThemeData();
     properties.add(EnumProperty<Brightness>('brightness', brightness, defaultValue: defaultData.brightness));
-    properties.add(DiagnosticsProperty<Color>('primaryColor', primaryColor, defaultValue: defaultData.primaryColor));
-    properties.add(DiagnosticsProperty<Color>('primaryContrastingColor', primaryContrastingColor, defaultValue: defaultData.primaryContrastingColor));
+    properties.add(ColorProperty('primaryColor', primaryColor, defaultValue: defaultData.primaryColor));
+    properties.add(ColorProperty('primaryContrastingColor', primaryContrastingColor, defaultValue: defaultData.primaryContrastingColor));
     properties.add(DiagnosticsProperty<CupertinoTextThemeData>('textTheme', textTheme, defaultValue: defaultData.textTheme));
-    properties.add(DiagnosticsProperty<Color>('barBackgroundColor', barBackgroundColor, defaultValue: defaultData.barBackgroundColor));
-    properties.add(DiagnosticsProperty<Color>('scaffoldBackgroundColor', scaffoldBackgroundColor, defaultValue: defaultData.scaffoldBackgroundColor));
+    properties.add(ColorProperty('barBackgroundColor', barBackgroundColor, defaultValue: defaultData.barBackgroundColor));
+    properties.add(ColorProperty('scaffoldBackgroundColor', scaffoldBackgroundColor, defaultValue: defaultData.scaffoldBackgroundColor));
   }
 }
 

packages/flutter/lib/src/foundation/diagnostics.dart

@@ -1515,7 +1515,8 @@ abstract class DiagnosticsNode {
 
   String get _separator => showSeparator ? ':' : '';
 
-  /// Serialize the node excluding its descendants to a JSON map.
+  /// Serialize the node to a JSON map according to the configuration provided
+  /// in the [DiagnosticsSerializationDelegate].
   ///
   /// Subclasses should override if they have additional properties that are
   /// useful for the GUI tools that consume this JSON.
@@ -1526,7 +1527,7 @@ abstract class DiagnosticsNode {
   ///    by this method and interactive tree views in the Flutter IntelliJ
   ///    plugin.
   @mustCallSuper
-  Map<String, Object> toJsonMap() {
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
     final Map<String, Object> data = <String, Object>{
       'description': toDescription(),
       'type': runtimeType.toString(),
@@ -1561,9 +1562,56 @@ abstract class DiagnosticsNode {
     if (allowNameWrap)
       data['allowNameWrap'] = allowNameWrap;
 
+    data.addAll(delegate.additionalNodeProperties(this));
+
+    if (delegate.includeProperties) {
+      final List<DiagnosticsNode> properties = getProperties();
+      data['properties'] = toJsonList(
+        delegate.filterProperties(properties, this),
+        this,
+        delegate,
+      );
+    }
+
+    if (delegate.subtreeDepth > 0) {
+      final List<DiagnosticsNode> children = getChildren();
+      data['children'] = toJsonList(
+        delegate.filterChildren(children, this),
+        this,
+        delegate,
+      );
+    }
+
     return data;
   }
 
+  /// Serializes a [List] of [DiagnosticsNode]s to a JSON list according to
+  /// the configuration provided by the [DiagnosticsSerializationDelegate].
+  ///
+  /// The provided `nodes` may be properties or children of the `parent`
+  /// [DiagnosticsNode].
+  static List<Map<String, Object>> toJsonList(
+      List<DiagnosticsNode> nodes,
+      DiagnosticsNode parent,
+      DiagnosticsSerializationDelegate delegate,
+  ) {
+    bool truncated = false;
+    if (nodes == null)
+      return const <Map<String, Object>>[];
+    final int originalNodeCount = nodes.length;
+    nodes = delegate.truncateNodesList(nodes, parent);
+    if (nodes.length != originalNodeCount) {
+      nodes.add(DiagnosticsNode.message('...'));
+      truncated = true;
+    }
+    final List<Map<String, Object>> json = nodes.map<Map<String, Object>>((DiagnosticsNode node) {
+      return node.toJsonMap(delegate.delegateForNode(node));
+    }).toList();
+    if (truncated)
+      json.last['truncated'] = true;
+    return json;
+  }
+
   /// Returns a string representation of this diagnostic that is compatible with
   /// the style of the parent if the node is not the root.
   ///
@@ -1751,8 +1799,8 @@ class StringProperty extends DiagnosticsProperty<String> {
   final bool quoted;
 
   @override
-  Map<String, Object> toJsonMap() {
-    final Map<String, Object> json = super.toJsonMap();
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
+    final Map<String, Object> json = super.toJsonMap(delegate);
     json['quoted'] = quoted;
     return json;
   }
@@ -1824,8 +1872,8 @@ abstract class _NumProperty<T extends num> extends DiagnosticsProperty<T> {
   );
 
   @override
-  Map<String, Object> toJsonMap() {
-    final Map<String, Object> json = super.toJsonMap();
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
+    final Map<String, Object> json = super.toJsonMap(delegate);
     if (unit != null)
       json['unit'] = unit;
 
@@ -2060,8 +2108,8 @@ class FlagProperty extends DiagnosticsProperty<bool> {
        );
 
   @override
-  Map<String, Object> toJsonMap() {
-    final Map<String, Object> json = super.toJsonMap();
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
+    final Map<String, Object> json = super.toJsonMap(delegate);
     if (ifTrue != null)
       json['ifTrue'] = ifTrue;
     if (ifFalse != null)
@@ -2194,8 +2242,8 @@ class IterableProperty<T> extends DiagnosticsProperty<Iterable<T>> {
   }
 
   @override
-  Map<String, Object> toJsonMap() {
-    final Map<String, Object> json = super.toJsonMap();
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
+    final Map<String, Object> json = super.toJsonMap(delegate);
     if (value != null) {
       json['values'] = value.map<String>((T value) => value.toString()).toList();
     }
@@ -2345,8 +2393,8 @@ class ObjectFlagProperty<T> extends DiagnosticsProperty<T> {
   }
 
   @override
-  Map<String, Object> toJsonMap() {
-    final Map<String, Object> json = super.toJsonMap();
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
+    final Map<String, Object> json = super.toJsonMap(delegate);
     if (ifPresent != null)
       json['ifPresent'] = ifPresent;
     return json;
@@ -2472,8 +2520,22 @@ class DiagnosticsProperty<T> extends DiagnosticsNode {
   final bool allowNameWrap;
 
   @override
-  Map<String, Object> toJsonMap() {
-    final Map<String, Object> json = super.toJsonMap();
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
+    final T v = value;
+    List<Map<String, Object>> properties;
+    if (delegate.expandPropertyValues && delegate.includeProperties && v is Diagnosticable && getProperties().isEmpty) {
+      // Exclude children for expanded nodes to avoid cycles.
+      delegate = delegate.copyWith(subtreeDepth: 0, includeProperties: false);
+      properties = DiagnosticsNode.toJsonList(
+        delegate.filterProperties(v.toDiagnosticsNode().getProperties(), this),
+        this,
+        delegate,
+      );
+    }
+    final Map<String, Object> json = super.toJsonMap(delegate);
+    if (properties != null) {
+      json['properties'] = properties;
+    }
     if (defaultValue != kNoDefaultValue)
       json['defaultValue'] = defaultValue.toString();
     if (ifEmpty != null)
@@ -2735,8 +2797,9 @@ class DiagnosticableNode<T extends Diagnosticable> extends DiagnosticsNode {
 }
 
 /// [DiagnosticsNode] for an instance of [DiagnosticableTree].
-class _DiagnosticableTreeNode extends DiagnosticableNode<DiagnosticableTree> {
-  _DiagnosticableTreeNode({
+class DiagnosticableTreeNode extends DiagnosticableNode<DiagnosticableTree> {
+  /// Creates a [DiagnosticableTreeNode].
+  DiagnosticableTreeNode({
     String name,
     @required DiagnosticableTree value,
     @required DiagnosticsTreeStyle style,
@@ -2975,6 +3038,10 @@ mixin DiagnosticableMixin {
   ///  * [ObjectFlagProperty], which provides terse descriptions of whether a
   ///    property value is present or not. For example, whether an `onClick`
   ///    callback is specified or an animation is in progress.
+  ///  * [ColorProperty], which must be used if the property value is
+  ///    a [Color] or one of its subclasses.
+  ///  * [IconDataProperty], which must be used if the property value
+  ///    is of type [IconData].
   ///
   /// If none of these subclasses apply, use the [DiagnosticsProperty]
   /// constructor or in rare cases create your own [DiagnosticsProperty]
@@ -3201,7 +3268,7 @@ abstract class DiagnosticableTree extends Diagnosticable {
 
   @override
   DiagnosticsNode toDiagnosticsNode({ String name, DiagnosticsTreeStyle style }) {
-    return _DiagnosticableTreeNode(
+    return DiagnosticableTreeNode(
       name: name,
       value: this,
       style: style,
@@ -3268,7 +3335,7 @@ mixin DiagnosticableTreeMixin implements DiagnosticableTree {
 
   @override
   DiagnosticsNode toDiagnosticsNode({ String name, DiagnosticsTreeStyle style }) {
-    return _DiagnosticableTreeNode(
+    return DiagnosticableTreeNode(
       name: name,
       value: this,
       style: style,
@@ -3334,3 +3401,159 @@ class DiagnosticsBlock extends DiagnosticsNode {
   @override
   String toDescription({TextTreeConfiguration parentConfiguration}) => _description;
 }
+
+/// A delegate that configures how a hierarchy of [DiagnosticsNode]s should be
+/// serialized.
+///
+/// Implement this class in a subclass to fully configure how [DiagnosticsNode]s
+/// get serialized.
+abstract class DiagnosticsSerializationDelegate {
+  /// Creates a simple [DiagnosticsSerializationDelegate] that controls the
+  /// [subtreeDepth] and whether to [includeProperties].
+  ///
+  /// For additional configuration options, extend
+  /// [DiagnosticsSerializationDelegate] and provide custom implementations
+  /// for the methods of this class.
+  const factory DiagnosticsSerializationDelegate({
+    int subtreeDepth,
+    bool includeProperties,
+  }) = _DefaultDiagnosticsSerializationDelegate;
+
+  /// Returns a serializable map of additional information that will be included
+  /// in the serialization of the given [DiagnosticsNode].
+  ///
+  /// This method is called for every [DiagnosticsNode] that's included in
+  /// the serialization.
+  Map<String, Object> additionalNodeProperties(DiagnosticsNode node);
+
+  /// Filters the list of [DiagnosticsNode]s that will be included as children
+  /// for the given `owner` node.
+  ///
+  /// The callback may return a subset of the children in the provided list
+  /// or replace the entire list with new child nodes.
+  ///
+  /// See also:
+  ///
+  ///  * [subtreeDepth], which controls how many levels of children will be
+  ///    included in the serialization.
+  List<DiagnosticsNode> filterChildren(List<DiagnosticsNode> nodes, DiagnosticsNode owner);
+
+  /// Filters the list of [DiagnosticsNode]s that will be included as properties
+  /// for the given `owner` node.
+  ///
+  /// The callback may return a subset of the properties in the provided list
+  /// or replace the entire list with new property nodes.
+  ///
+  /// By default, `nodes` is returned as-is.
+  ///
+  /// See also:
+  ///
+  ///  * [includeProperties], which controls whether properties will be included
+  ///    at all.
+  List<DiagnosticsNode> filterProperties(List<DiagnosticsNode> nodes, DiagnosticsNode owner);
+
+  /// Truncates the given list of [DiagnosticsNode] that will be added to the
+  /// serialization as children or properties of the `owner` node.
+  ///
+  /// The method must return a subset of the provided nodes and may
+  /// not replace any nodes. While [filterProperties] and [filterChildren]
+  /// completely hide a node from the serialization, truncating a node will
+  /// leave a hint in the serialization that there were additional nodes in the
+  /// result that are not included in the current serialization.
+  ///
+  /// By default, `nodes` is returned as-is.
+  List<DiagnosticsNode> truncateNodesList(List<DiagnosticsNode> nodes, DiagnosticsNode owner);
+
+  /// Returns the [DiagnosticsSerializationDelegate] to be used
+  /// for adding the provided [DiagnosticsNode] to the serialization.
+  ///
+  /// By default, this will return a copy of this delegate, which has the
+  /// [subtreeDepth] reduced by one.
+  ///
+  /// This is called for nodes that will be added to the serialization as
+  /// property or child of another node. It may return the same delegate if no
+  /// changes to it are necessary.
+  DiagnosticsSerializationDelegate delegateForNode(DiagnosticsNode node);
+
+  /// Controls how many levels of children will be included in the serialized
+  /// hierarchy of [DiagnosticsNode]s.
+  ///
+  /// Defaults to zero.
+  ///
+  /// See also:
+  ///
+  ///  * [filterChildren], which provides a way to filter the children that
+  ///    will be included.
+  int get subtreeDepth;
+
+  /// Whether to include the properties of a [DiagnosticsNode] in the
+  /// serialization.
+  ///
+  /// Defaults to false.
+  ///
+  /// See also:
+  ///
+  ///  * [filterProperties], which provides a way to filter the properties that
+  ///    will be included.
+  bool get includeProperties;
+
+  /// Whether properties that have a [Diagnosticable] as value should be
+  /// expanded.
+  bool get expandPropertyValues;
+
+  /// Creates a copy of this [DiagnosticsSerializationDelegate] with the
+  /// provided values.
+  DiagnosticsSerializationDelegate copyWith({
+    int subtreeDepth,
+    bool includeProperties,
+  });
+}
+
+class _DefaultDiagnosticsSerializationDelegate implements DiagnosticsSerializationDelegate {
+  const _DefaultDiagnosticsSerializationDelegate({
+    this.includeProperties = false,
+    this.subtreeDepth = 0,
+  });
+
+  @override
+  Map<String, Object> additionalNodeProperties(DiagnosticsNode node) {
+    return const <String, Object>{};
+  }
+
+  @override
+  DiagnosticsSerializationDelegate delegateForNode(DiagnosticsNode node) {
+    return subtreeDepth > 0 ? copyWith(subtreeDepth: subtreeDepth - 1) : this;
+  }
+
+  @override
+  bool get expandPropertyValues => false;
+
+  @override
+  List<DiagnosticsNode> filterChildren(List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+    return nodes;
+  }
+
+  @override
+  List<DiagnosticsNode> filterProperties(List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+    return nodes;
+  }
+
+  @override
+  final bool includeProperties;
+
+  @override
+  final int subtreeDepth;
+
+  @override
+  List<DiagnosticsNode> truncateNodesList(List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+    return nodes;
+  }
+
+  @override
+  DiagnosticsSerializationDelegate copyWith({int subtreeDepth, bool includeProperties}) {
+    return _DefaultDiagnosticsSerializationDelegate(
+      subtreeDepth: subtreeDepth ?? this.subtreeDepth,
+      includeProperties: includeProperties ?? this.includeProperties,
+    );
+  }
+}

packages/flutter/lib/src/material/app_bar_theme.dart

@@ -141,7 +141,7 @@ class AppBarTheme extends Diagnosticable {
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
     properties.add(DiagnosticsProperty<Brightness>('brightness', brightness, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
     properties.add(DiagnosticsProperty<double>('elevation', elevation, defaultValue: null));
     properties.add(DiagnosticsProperty<IconThemeData>('iconTheme', iconTheme, defaultValue: null));
     properties.add(DiagnosticsProperty<IconThemeData>('actionsIconTheme', actionsIconTheme, defaultValue: null));

packages/flutter/lib/src/material/bottom_app_bar_theme.dart

@@ -101,7 +101,7 @@ class BottomAppBarTheme extends Diagnosticable {
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
     properties.add(DiagnosticsProperty<double>('elevation', elevation, defaultValue: null));
     properties.add(DiagnosticsProperty<NotchedShape>('shape', shape, defaultValue: null));
   }

packages/flutter/lib/src/material/bottom_sheet_theme.dart

@@ -104,7 +104,7 @@ class BottomSheetThemeData extends Diagnosticable {
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
-    properties.add(DiagnosticsProperty<Color>('backgroundColor', backgroundColor, defaultValue: null));
+    properties.add(ColorProperty('backgroundColor', backgroundColor, defaultValue: null));
     properties.add(DoubleProperty('elevation', elevation, defaultValue: null));
     properties.add(DiagnosticsProperty<ShapeBorder>('shape', shape, defaultValue: null));
   }

packages/flutter/lib/src/material/button_theme.dart

@@ -925,12 +925,12 @@ class ButtonThemeData extends Diagnosticable {
       defaultValue: defaultTheme.alignedDropdown,
       ifTrue: 'dropdown width matches button',
     ));
-    properties.add(DiagnosticsProperty<Color>('buttonColor', _buttonColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('disabledColor', _disabledColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('focusColor', _focusColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('hoverColor', _hoverColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('highlightColor', _highlightColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('splashColor', _splashColor, defaultValue: null));
+    properties.add(ColorProperty('buttonColor', _buttonColor, defaultValue: null));
+    properties.add(ColorProperty('disabledColor', _disabledColor, defaultValue: null));
+    properties.add(ColorProperty('focusColor', _focusColor, defaultValue: null));
+    properties.add(ColorProperty('hoverColor', _hoverColor, defaultValue: null));
+    properties.add(ColorProperty('highlightColor', _highlightColor, defaultValue: null));
+    properties.add(ColorProperty('splashColor', _splashColor, defaultValue: null));
     properties.add(DiagnosticsProperty<ColorScheme>('colorScheme', colorScheme, defaultValue: defaultTheme.colorScheme));
     properties.add(DiagnosticsProperty<MaterialTapTargetSize>('materialTapTargetSize', _materialTapTargetSize, defaultValue: null));
   }

packages/flutter/lib/src/material/card_theme.dart

@@ -134,7 +134,7 @@ class CardTheme extends Diagnosticable {
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
     properties.add(DiagnosticsProperty<Clip>('clipBehavior', clipBehavior, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
     properties.add(DiagnosticsProperty<double>('elevation', elevation, defaultValue: null));
     properties.add(DiagnosticsProperty<EdgeInsetsGeometry>('margin', margin, defaultValue: null));
     properties.add(DiagnosticsProperty<ShapeBorder>('shape', shape, defaultValue: null));

packages/flutter/lib/src/material/chip_theme.dart

@@ -486,13 +486,13 @@ class ChipThemeData extends Diagnosticable {
       brightness: defaultTheme.brightness,
       labelStyle: defaultTheme.textTheme.body2,
     );
-    properties.add(DiagnosticsProperty<Color>('backgroundColor', backgroundColor, defaultValue: defaultData.backgroundColor));
-    properties.add(DiagnosticsProperty<Color>('deleteIconColor', deleteIconColor, defaultValue: defaultData.deleteIconColor));
-    properties.add(DiagnosticsProperty<Color>('disabledColor', disabledColor, defaultValue: defaultData.disabledColor));
-    properties.add(DiagnosticsProperty<Color>('selectedColor', selectedColor, defaultValue: defaultData.selectedColor));
-    properties.add(DiagnosticsProperty<Color>('secondarySelectedColor', secondarySelectedColor, defaultValue: defaultData.secondarySelectedColor));
-    properties.add(DiagnosticsProperty<Color>('shadowColor', shadowColor, defaultValue: defaultData.shadowColor));
-    properties.add(DiagnosticsProperty<Color>('selectedShadowColor', selectedShadowColor, defaultValue: defaultData.selectedShadowColor));
+    properties.add(ColorProperty('backgroundColor', backgroundColor, defaultValue: defaultData.backgroundColor));
+    properties.add(ColorProperty('deleteIconColor', deleteIconColor, defaultValue: defaultData.deleteIconColor));
+    properties.add(ColorProperty('disabledColor', disabledColor, defaultValue: defaultData.disabledColor));
+    properties.add(ColorProperty('selectedColor', selectedColor, defaultValue: defaultData.selectedColor));
+    properties.add(ColorProperty('secondarySelectedColor', secondarySelectedColor, defaultValue: defaultData.secondarySelectedColor));
+    properties.add(ColorProperty('shadowColor', shadowColor, defaultValue: defaultData.shadowColor));
+    properties.add(ColorProperty('selectedShadowColor', selectedShadowColor, defaultValue: defaultData.selectedShadowColor));
     properties.add(DiagnosticsProperty<EdgeInsetsGeometry>('labelPadding', labelPadding, defaultValue: defaultData.labelPadding));
     properties.add(DiagnosticsProperty<EdgeInsetsGeometry>('padding', padding, defaultValue: defaultData.padding));
     properties.add(DiagnosticsProperty<ShapeBorder>('shape', shape, defaultValue: defaultData.shape));

packages/flutter/lib/src/material/color_scheme.dart

@@ -307,18 +307,18 @@ class ColorScheme extends Diagnosticable {
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
     const ColorScheme defaultScheme = ColorScheme.light();
-    properties.add(DiagnosticsProperty<Color>('primary', primary, defaultValue: defaultScheme.primary));
-    properties.add(DiagnosticsProperty<Color>('primaryVariant', primaryVariant, defaultValue: defaultScheme.primaryVariant));
-    properties.add(DiagnosticsProperty<Color>('secondary', secondary, defaultValue: defaultScheme.secondary));
-    properties.add(DiagnosticsProperty<Color>('secondaryVariant', secondaryVariant, defaultValue: defaultScheme.secondaryVariant));
-    properties.add(DiagnosticsProperty<Color>('surface', surface, defaultValue: defaultScheme.surface));
-    properties.add(DiagnosticsProperty<Color>('background', background, defaultValue: defaultScheme.background));
-    properties.add(DiagnosticsProperty<Color>('error', error, defaultValue: defaultScheme.error));
-    properties.add(DiagnosticsProperty<Color>('onPrimary', onPrimary, defaultValue: defaultScheme.onPrimary));
-    properties.add(DiagnosticsProperty<Color>('onSecondary', onSecondary, defaultValue: defaultScheme.onSecondary));
-    properties.add(DiagnosticsProperty<Color>('onSurface', onSurface, defaultValue: defaultScheme.onSurface));
-    properties.add(DiagnosticsProperty<Color>('onBackground', onBackground, defaultValue: defaultScheme.onBackground));
-    properties.add(DiagnosticsProperty<Color>('onError', onError, defaultValue: defaultScheme.onError));
+    properties.add(ColorProperty('primary', primary, defaultValue: defaultScheme.primary));
+    properties.add(ColorProperty('primaryVariant', primaryVariant, defaultValue: defaultScheme.primaryVariant));
+    properties.add(ColorProperty('secondary', secondary, defaultValue: defaultScheme.secondary));
+    properties.add(ColorProperty('secondaryVariant', secondaryVariant, defaultValue: defaultScheme.secondaryVariant));
+    properties.add(ColorProperty('surface', surface, defaultValue: defaultScheme.surface));
+    properties.add(ColorProperty('background', background, defaultValue: defaultScheme.background));
+    properties.add(ColorProperty('error', error, defaultValue: defaultScheme.error));
+    properties.add(ColorProperty('onPrimary', onPrimary, defaultValue: defaultScheme.onPrimary));
+    properties.add(ColorProperty('onSecondary', onSecondary, defaultValue: defaultScheme.onSecondary));
+    properties.add(ColorProperty('onSurface', onSurface, defaultValue: defaultScheme.onSurface));
+    properties.add(ColorProperty('onBackground', onBackground, defaultValue: defaultScheme.onBackground));
+    properties.add(ColorProperty('onError', onError, defaultValue: defaultScheme.onError));
     properties.add(DiagnosticsProperty<Brightness>('brightness', brightness, defaultValue: defaultScheme.brightness));
   }
 }

packages/flutter/lib/src/material/dialog_theme.dart

@@ -120,7 +120,7 @@ class DialogTheme extends Diagnosticable {
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
-    properties.add(DiagnosticsProperty<Color>('backgroundColor', backgroundColor));
+    properties.add(ColorProperty('backgroundColor', backgroundColor));
     properties.add(DiagnosticsProperty<ShapeBorder>('shape', shape, defaultValue: null));
     properties.add(DoubleProperty('elevation', elevation));
     properties.add(DiagnosticsProperty<TextStyle>('titleTextStyle', titleTextStyle, defaultValue: null));

packages/flutter/lib/src/material/floating_action_button.dart

@@ -485,10 +485,10 @@ class FloatingActionButton extends StatelessWidget {
     super.debugFillProperties(properties);
     properties.add(ObjectFlagProperty<VoidCallback>('onPressed', onPressed, ifNull: 'disabled'));
     properties.add(StringProperty('tooltip', tooltip, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('foregroundColor', foregroundColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('backgroundColor', backgroundColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('focusColor', focusColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('hoverColor', hoverColor, defaultValue: null));
+    properties.add(ColorProperty('foregroundColor', foregroundColor, defaultValue: null));
+    properties.add(ColorProperty('backgroundColor', backgroundColor, defaultValue: null));
+    properties.add(ColorProperty('focusColor', focusColor, defaultValue: null));
+    properties.add(ColorProperty('hoverColor', hoverColor, defaultValue: null));
     properties.add(ObjectFlagProperty<Object>('heroTag', heroTag, ifPresent: 'hero'));
     properties.add(DiagnosticsProperty<double>('elevation', elevation, defaultValue: null));
     properties.add(DiagnosticsProperty<double>('focusElevation', focusElevation, defaultValue: null));

packages/flutter/lib/src/material/floating_action_button_theme.dart

@@ -175,10 +175,10 @@ class FloatingActionButtonThemeData extends Diagnosticable {
     super.debugFillProperties(properties);
     const FloatingActionButtonThemeData defaultData = FloatingActionButtonThemeData();
 
-    properties.add(DiagnosticsProperty<Color>('foregroundColor', foregroundColor, defaultValue: defaultData.foregroundColor));
-    properties.add(DiagnosticsProperty<Color>('backgroundColor', backgroundColor, defaultValue: defaultData.backgroundColor));
-    properties.add(DiagnosticsProperty<Color>('focusColor', focusColor, defaultValue: defaultData.focusColor));
-    properties.add(DiagnosticsProperty<Color>('hoverColor', hoverColor, defaultValue: defaultData.hoverColor));
+    properties.add(ColorProperty('foregroundColor', foregroundColor, defaultValue: defaultData.foregroundColor));
+    properties.add(ColorProperty('backgroundColor', backgroundColor, defaultValue: defaultData.backgroundColor));
+    properties.add(ColorProperty('focusColor', focusColor, defaultValue: defaultData.focusColor));
+    properties.add(ColorProperty('hoverColor', hoverColor, defaultValue: defaultData.hoverColor));
     properties.add(DoubleProperty('elevation', elevation, defaultValue: defaultData.elevation));
     properties.add(DoubleProperty('focusElevation', focusElevation, defaultValue: defaultData.focusElevation));
     properties.add(DoubleProperty('hoverElevation', hoverElevation, defaultValue: defaultData.hoverElevation));

packages/flutter/lib/src/material/icon_button.dart

@@ -334,12 +334,12 @@ class IconButton extends StatelessWidget {
     properties.add(DiagnosticsProperty<Widget>('icon', icon, showName: false));
     properties.add(StringProperty('tooltip', tooltip, defaultValue: null, quoted: false));
     properties.add(ObjectFlagProperty<VoidCallback>('onPressed', onPressed, ifNull: 'disabled'));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('disabledColor', disabledColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('focusColor', focusColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('hoverColor', hoverColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('highlightColor', highlightColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('splashColor', splashColor, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
+    properties.add(ColorProperty('disabledColor', disabledColor, defaultValue: null));
+    properties.add(ColorProperty('focusColor', focusColor, defaultValue: null));
+    properties.add(ColorProperty('hoverColor', hoverColor, defaultValue: null));
+    properties.add(ColorProperty('highlightColor', highlightColor, defaultValue: null));
+    properties.add(ColorProperty('splashColor', splashColor, defaultValue: null));
     properties.add(DiagnosticsProperty<EdgeInsetsGeometry>('padding', padding, defaultValue: null));
     properties.add(DiagnosticsProperty<FocusNode>('focusNode', focusNode, defaultValue: null));
   }

packages/flutter/lib/src/material/input_decorator.dart

@@ -3456,9 +3456,9 @@ class InputDecorationTheme extends Diagnosticable {
     properties.add(DiagnosticsProperty<TextStyle>('suffixStyle', suffixStyle, defaultValue: defaultTheme.suffixStyle));
     properties.add(DiagnosticsProperty<TextStyle>('counterStyle', counterStyle, defaultValue: defaultTheme.counterStyle));
     properties.add(DiagnosticsProperty<bool>('filled', filled, defaultValue: defaultTheme.filled));
-    properties.add(DiagnosticsProperty<Color>('fillColor', fillColor, defaultValue: defaultTheme.fillColor));
-    properties.add(DiagnosticsProperty<Color>('focusColor', focusColor, defaultValue: defaultTheme.focusColor));
-    properties.add(DiagnosticsProperty<Color>('hoverColor', hoverColor, defaultValue: defaultTheme.hoverColor));
+    properties.add(ColorProperty('fillColor', fillColor, defaultValue: defaultTheme.fillColor));
+    properties.add(ColorProperty('focusColor', focusColor, defaultValue: defaultTheme.focusColor));
+    properties.add(ColorProperty('hoverColor', hoverColor, defaultValue: defaultTheme.hoverColor));
     properties.add(DiagnosticsProperty<InputBorder>('errorBorder', errorBorder, defaultValue: defaultTheme.errorBorder));
     properties.add(DiagnosticsProperty<InputBorder>('focusedBorder', focusedBorder, defaultValue: defaultTheme.focusedErrorBorder));
     properties.add(DiagnosticsProperty<InputBorder>('focusedErrorBorder', focusedErrorBorder, defaultValue: defaultTheme.focusedErrorBorder));

packages/flutter/lib/src/material/material.dart

@@ -289,8 +289,8 @@ class Material extends StatefulWidget {
     super.debugFillProperties(properties);
     properties.add(EnumProperty<MaterialType>('type', type));
     properties.add(DoubleProperty('elevation', elevation, defaultValue: 0.0));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('shadowColor', shadowColor, defaultValue: const Color(0xFF000000)));
+    properties.add(ColorProperty('color', color, defaultValue: null));
+    properties.add(ColorProperty('shadowColor', shadowColor, defaultValue: const Color(0xFF000000)));
     textStyle?.debugFillProperties(properties, prefix: 'textStyle.');
     properties.add(DiagnosticsProperty<ShapeBorder>('shape', shape, defaultValue: null));
     properties.add(DiagnosticsProperty<bool>('borderOnForeground', borderOnForeground, defaultValue: true));
@@ -691,8 +691,8 @@ class _MaterialInterior extends ImplicitlyAnimatedWidget {
     super.debugFillProperties(description);
     description.add(DiagnosticsProperty<ShapeBorder>('shape', shape));
     description.add(DoubleProperty('elevation', elevation));
-    description.add(DiagnosticsProperty<Color>('color', color));
-    description.add(DiagnosticsProperty<Color>('shadowColor', shadowColor));
+    description.add(ColorProperty('color', color));
+    description.add(ColorProperty('shadowColor', shadowColor));
   }
 }
 

packages/flutter/lib/src/material/material_button.dart

@@ -359,14 +359,14 @@ class MaterialButton extends StatelessWidget {
     super.debugFillProperties(properties);
     properties.add(ObjectFlagProperty<VoidCallback>('onPressed', onPressed, ifNull: 'disabled'));
     properties.add(DiagnosticsProperty<ButtonTextTheme>('textTheme', textTheme, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('textColor', textColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('disabledTextColor', disabledTextColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('disabledColor', disabledColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('focusColor', focusColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('hoverColor', hoverColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('highlightColor', highlightColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('splashColor', splashColor, defaultValue: null));
+    properties.add(ColorProperty('textColor', textColor, defaultValue: null));
+    properties.add(ColorProperty('disabledTextColor', disabledTextColor, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
+    properties.add(ColorProperty('disabledColor', disabledColor, defaultValue: null));
+    properties.add(ColorProperty('focusColor', focusColor, defaultValue: null));
+    properties.add(ColorProperty('hoverColor', hoverColor, defaultValue: null));
+    properties.add(ColorProperty('highlightColor', highlightColor, defaultValue: null));
+    properties.add(ColorProperty('splashColor', splashColor, defaultValue: null));
     properties.add(DiagnosticsProperty<Brightness>('colorBrightness', colorBrightness, defaultValue: null));
     properties.add(DiagnosticsProperty<EdgeInsetsGeometry>('padding', padding, defaultValue: null));
     properties.add(DiagnosticsProperty<ShapeBorder>('shape', shape, defaultValue: null));

packages/flutter/lib/src/material/outline_button.dart

@@ -180,8 +180,8 @@ class OutlineButton extends MaterialButton {
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
     properties.add(DiagnosticsProperty<BorderSide>('borderSide', borderSide, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('disabledBorderColor', disabledBorderColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('highlightedBorderColor', highlightedBorderColor, defaultValue: null));
+    properties.add(ColorProperty('disabledBorderColor', disabledBorderColor, defaultValue: null));
+    properties.add(ColorProperty('highlightedBorderColor', highlightedBorderColor, defaultValue: null));
   }
 }
 

packages/flutter/lib/src/material/slider_theme.dart

@@ -811,20 +811,19 @@ class SliderThemeData extends Diagnosticable {
     super.debugFillProperties(properties);
     const SliderThemeData defaultData = SliderThemeData();
     properties.add(DoubleProperty('trackHeight', trackHeight, defaultValue: defaultData.trackHeight));
-    properties.add(DiagnosticsProperty<Color>('activeTrackColor', activeTrackColor, defaultValue: defaultData.activeTrackColor));
-    properties.add(DiagnosticsProperty<Color>('activeTrackColor', activeTrackColor, defaultValue: defaultData.activeTrackColor));
-    properties.add(DiagnosticsProperty<Color>('inactiveTrackColor', inactiveTrackColor, defaultValue: defaultData.inactiveTrackColor));
-    properties.add(DiagnosticsProperty<Color>('disabledActiveTrackColor', disabledActiveTrackColor, defaultValue: defaultData.disabledActiveTrackColor));
-    properties.add(DiagnosticsProperty<Color>('disabledInactiveTrackColor', disabledInactiveTrackColor, defaultValue: defaultData.disabledInactiveTrackColor));
-    properties.add(DiagnosticsProperty<Color>('activeTickMarkColor', activeTickMarkColor, defaultValue: defaultData.activeTickMarkColor));
-    properties.add(DiagnosticsProperty<Color>('inactiveTickMarkColor', inactiveTickMarkColor, defaultValue: defaultData.inactiveTickMarkColor));
-    properties.add(DiagnosticsProperty<Color>('disabledActiveTickMarkColor', disabledActiveTickMarkColor, defaultValue: defaultData.disabledActiveTickMarkColor));
-    properties.add(DiagnosticsProperty<Color>('disabledInactiveTickMarkColor', disabledInactiveTickMarkColor, defaultValue: defaultData.disabledInactiveTickMarkColor));
-    properties.add(DiagnosticsProperty<Color>('thumbColor', thumbColor, defaultValue: defaultData.thumbColor));
-    properties.add(DiagnosticsProperty<Color>('overlappingShapeStrokeColor', overlappingShapeStrokeColor, defaultValue: defaultData.overlappingShapeStrokeColor));
-    properties.add(DiagnosticsProperty<Color>('disabledThumbColor', disabledThumbColor, defaultValue: defaultData.disabledThumbColor));
-    properties.add(DiagnosticsProperty<Color>('overlayColor', overlayColor, defaultValue: defaultData.overlayColor));
-    properties.add(DiagnosticsProperty<Color>('valueIndicatorColor', valueIndicatorColor, defaultValue: defaultData.valueIndicatorColor));
+    properties.add(ColorProperty('activeTrackColor', activeTrackColor, defaultValue: defaultData.activeTrackColor));
+    properties.add(ColorProperty('inactiveTrackColor', inactiveTrackColor, defaultValue: defaultData.inactiveTrackColor));
+    properties.add(ColorProperty('disabledActiveTrackColor', disabledActiveTrackColor, defaultValue: defaultData.disabledActiveTrackColor));
+    properties.add(ColorProperty('disabledInactiveTrackColor', disabledInactiveTrackColor, defaultValue: defaultData.disabledInactiveTrackColor));
+    properties.add(ColorProperty('activeTickMarkColor', activeTickMarkColor, defaultValue: defaultData.activeTickMarkColor));
+    properties.add(ColorProperty('inactiveTickMarkColor', inactiveTickMarkColor, defaultValue: defaultData.inactiveTickMarkColor));
+    properties.add(ColorProperty('disabledActiveTickMarkColor', disabledActiveTickMarkColor, defaultValue: defaultData.disabledActiveTickMarkColor));
+    properties.add(ColorProperty('disabledInactiveTickMarkColor', disabledInactiveTickMarkColor, defaultValue: defaultData.disabledInactiveTickMarkColor));
+    properties.add(ColorProperty('thumbColor', thumbColor, defaultValue: defaultData.thumbColor));
+    properties.add(ColorProperty('overlappingShapeStrokeColor', overlappingShapeStrokeColor, defaultValue: defaultData.overlappingShapeStrokeColor));
+    properties.add(ColorProperty('disabledThumbColor', disabledThumbColor, defaultValue: defaultData.disabledThumbColor));
+    properties.add(ColorProperty('overlayColor', overlayColor, defaultValue: defaultData.overlayColor));
+    properties.add(ColorProperty('valueIndicatorColor', valueIndicatorColor, defaultValue: defaultData.valueIndicatorColor));
     properties.add(DiagnosticsProperty<SliderComponentShape>('overlayShape', overlayShape, defaultValue: defaultData.overlayShape));
     properties.add(DiagnosticsProperty<SliderTickMarkShape>('tickMarkShape', tickMarkShape, defaultValue: defaultData.tickMarkShape));
     properties.add(DiagnosticsProperty<SliderComponentShape>('thumbShape', thumbShape, defaultValue: defaultData.thumbShape));
@@ -836,7 +835,7 @@ class SliderThemeData extends Diagnosticable {
     properties.add(DiagnosticsProperty<RangeSliderValueIndicatorShape>('rangeValueIndicatorShape', rangeValueIndicatorShape, defaultValue: defaultData.rangeValueIndicatorShape));
     properties.add(EnumProperty<ShowValueIndicator>('showValueIndicator', showValueIndicator, defaultValue: defaultData.showValueIndicator));
     properties.add(DiagnosticsProperty<TextStyle>('valueIndicatorTextStyle', valueIndicatorTextStyle, defaultValue: defaultData.valueIndicatorTextStyle));
-    properties.add(DiagnosticsProperty<double>('minThumbSeparation', minThumbSeparation, defaultValue: defaultData.minThumbSeparation));
+    properties.add(DoubleProperty('minThumbSeparation', minThumbSeparation, defaultValue: defaultData.minThumbSeparation));
     properties.add(DiagnosticsProperty<RangeThumbSelector>('thumbSelector', thumbSelector, defaultValue: defaultData.thumbSelector));
   }
 }

packages/flutter/lib/src/material/snack_bar_theme.dart

@@ -163,9 +163,9 @@ class SnackBarThemeData extends Diagnosticable {
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
-    properties.add(DiagnosticsProperty<Color>('backgroundColor', backgroundColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('actionTextColor', actionTextColor, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('disabledActionTextColor', disabledActionTextColor, defaultValue: null));
+    properties.add(ColorProperty('backgroundColor', backgroundColor, defaultValue: null));
+    properties.add(ColorProperty('actionTextColor', actionTextColor, defaultValue: null));
+    properties.add(ColorProperty('disabledActionTextColor', disabledActionTextColor, defaultValue: null));
     properties.add(DoubleProperty('elevation', elevation, defaultValue: null));
     properties.add(DiagnosticsProperty<ShapeBorder>('shape', shape, defaultValue: null));
     properties.add(DiagnosticsProperty<SnackBarBehavior>('behavior', behavior, defaultValue: null));

packages/flutter/lib/src/material/text_field.dart

@@ -509,7 +509,7 @@ class TextField extends StatefulWidget {
     properties.add(EnumProperty<TextDirection>('textDirection', textDirection, defaultValue: null));
     properties.add(DoubleProperty('cursorWidth', cursorWidth, defaultValue: 2.0));
     properties.add(DiagnosticsProperty<Radius>('cursorRadius', cursorRadius, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('cursorColor', cursorColor, defaultValue: null));
+    properties.add(ColorProperty('cursorColor', cursorColor, defaultValue: null));
     properties.add(DiagnosticsProperty<Brightness>('keyboardAppearance', keyboardAppearance, defaultValue: null));
     properties.add(DiagnosticsProperty<EdgeInsetsGeometry>('scrollPadding', scrollPadding, defaultValue: const EdgeInsets.all(20.0)));
     properties.add(FlagProperty('selectionEnabled', value: selectionEnabled, defaultValue: true, ifFalse: 'selection disabled'));

packages/flutter/lib/src/material/theme_data.dart

@@ -1120,33 +1120,33 @@ class ThemeData extends Diagnosticable {
     final ThemeData defaultData = ThemeData.fallback();
     properties.add(EnumProperty<TargetPlatform>('platform', platform, defaultValue: defaultTargetPlatform));
     properties.add(EnumProperty<Brightness>('brightness', brightness, defaultValue: defaultData.brightness));
-    properties.add(DiagnosticsProperty<Color>('primaryColor', primaryColor, defaultValue: defaultData.primaryColor));
+    properties.add(ColorProperty('primaryColor', primaryColor, defaultValue: defaultData.primaryColor));
     properties.add(EnumProperty<Brightness>('primaryColorBrightness', primaryColorBrightness, defaultValue: defaultData.primaryColorBrightness));
-    properties.add(DiagnosticsProperty<Color>('accentColor', accentColor, defaultValue: defaultData.accentColor));
+    properties.add(ColorProperty('accentColor', accentColor, defaultValue: defaultData.accentColor));
     properties.add(EnumProperty<Brightness>('accentColorBrightness', accentColorBrightness, defaultValue: defaultData.accentColorBrightness));
-    properties.add(DiagnosticsProperty<Color>('canvasColor', canvasColor, defaultValue: defaultData.canvasColor));
-    properties.add(DiagnosticsProperty<Color>('scaffoldBackgroundColor', scaffoldBackgroundColor, defaultValue: defaultData.scaffoldBackgroundColor));
-    properties.add(DiagnosticsProperty<Color>('bottomAppBarColor', bottomAppBarColor, defaultValue: defaultData.bottomAppBarColor));
-    properties.add(DiagnosticsProperty<Color>('cardColor', cardColor, defaultValue: defaultData.cardColor));
-    properties.add(DiagnosticsProperty<Color>('dividerColor', dividerColor, defaultValue: defaultData.dividerColor));
-    properties.add(DiagnosticsProperty<Color>('focusColor', focusColor, defaultValue: defaultData.focusColor));
-    properties.add(DiagnosticsProperty<Color>('hoverColor', hoverColor, defaultValue: defaultData.hoverColor));
-    properties.add(DiagnosticsProperty<Color>('highlightColor', highlightColor, defaultValue: defaultData.highlightColor));
-    properties.add(DiagnosticsProperty<Color>('splashColor', splashColor, defaultValue: defaultData.splashColor));
-    properties.add(DiagnosticsProperty<Color>('selectedRowColor', selectedRowColor, defaultValue: defaultData.selectedRowColor));
-    properties.add(DiagnosticsProperty<Color>('unselectedWidgetColor', unselectedWidgetColor, defaultValue: defaultData.unselectedWidgetColor));
-    properties.add(DiagnosticsProperty<Color>('disabledColor', disabledColor, defaultValue: defaultData.disabledColor));
-    properties.add(DiagnosticsProperty<Color>('buttonColor', buttonColor, defaultValue: defaultData.buttonColor));
-    properties.add(DiagnosticsProperty<Color>('secondaryHeaderColor', secondaryHeaderColor, defaultValue: defaultData.secondaryHeaderColor));
-    properties.add(DiagnosticsProperty<Color>('textSelectionColor', textSelectionColor, defaultValue: defaultData.textSelectionColor));
-    properties.add(DiagnosticsProperty<Color>('cursorColor', cursorColor, defaultValue: defaultData.cursorColor));
-    properties.add(DiagnosticsProperty<Color>('textSelectionHandleColor', textSelectionHandleColor, defaultValue: defaultData.textSelectionHandleColor));
-    properties.add(DiagnosticsProperty<Color>('backgroundColor', backgroundColor, defaultValue: defaultData.backgroundColor));
-    properties.add(DiagnosticsProperty<Color>('dialogBackgroundColor', dialogBackgroundColor, defaultValue: defaultData.dialogBackgroundColor));
-    properties.add(DiagnosticsProperty<Color>('indicatorColor', indicatorColor, defaultValue: defaultData.indicatorColor));
-    properties.add(DiagnosticsProperty<Color>('hintColor', hintColor, defaultValue: defaultData.hintColor));
-    properties.add(DiagnosticsProperty<Color>('errorColor', errorColor, defaultValue: defaultData.errorColor));
-    properties.add(DiagnosticsProperty<Color>('toggleableActiveColor', toggleableActiveColor, defaultValue: defaultData.toggleableActiveColor));
+    properties.add(ColorProperty('canvasColor', canvasColor, defaultValue: defaultData.canvasColor));
+    properties.add(ColorProperty('scaffoldBackgroundColor', scaffoldBackgroundColor, defaultValue: defaultData.scaffoldBackgroundColor));
+    properties.add(ColorProperty('bottomAppBarColor', bottomAppBarColor, defaultValue: defaultData.bottomAppBarColor));
+    properties.add(ColorProperty('cardColor', cardColor, defaultValue: defaultData.cardColor));
+    properties.add(ColorProperty('dividerColor', dividerColor, defaultValue: defaultData.dividerColor));
+    properties.add(ColorProperty('focusColor', focusColor, defaultValue: defaultData.focusColor));
+    properties.add(ColorProperty('hoverColor', hoverColor, defaultValue: defaultData.hoverColor));
+    properties.add(ColorProperty('highlightColor', highlightColor, defaultValue: defaultData.highlightColor));
+    properties.add(ColorProperty('splashColor', splashColor, defaultValue: defaultData.splashColor));
+    properties.add(ColorProperty('selectedRowColor', selectedRowColor, defaultValue: defaultData.selectedRowColor));
+    properties.add(ColorProperty('unselectedWidgetColor', unselectedWidgetColor, defaultValue: defaultData.unselectedWidgetColor));
+    properties.add(ColorProperty('disabledColor', disabledColor, defaultValue: defaultData.disabledColor));
+    properties.add(ColorProperty('buttonColor', buttonColor, defaultValue: defaultData.buttonColor));
+    properties.add(ColorProperty('secondaryHeaderColor', secondaryHeaderColor, defaultValue: defaultData.secondaryHeaderColor));
+    properties.add(ColorProperty('textSelectionColor', textSelectionColor, defaultValue: defaultData.textSelectionColor));
+    properties.add(ColorProperty('cursorColor', cursorColor, defaultValue: defaultData.cursorColor));
+    properties.add(ColorProperty('textSelectionHandleColor', textSelectionHandleColor, defaultValue: defaultData.textSelectionHandleColor));
+    properties.add(ColorProperty('backgroundColor', backgroundColor, defaultValue: defaultData.backgroundColor));
+    properties.add(ColorProperty('dialogBackgroundColor', dialogBackgroundColor, defaultValue: defaultData.dialogBackgroundColor));
+    properties.add(ColorProperty('indicatorColor', indicatorColor, defaultValue: defaultData.indicatorColor));
+    properties.add(ColorProperty('hintColor', hintColor, defaultValue: defaultData.hintColor));
+    properties.add(ColorProperty('errorColor', errorColor, defaultValue: defaultData.errorColor));
+    properties.add(ColorProperty('toggleableActiveColor', toggleableActiveColor, defaultValue: defaultData.toggleableActiveColor));
     properties.add(DiagnosticsProperty<ButtonThemeData>('buttonTheme', buttonTheme));
     properties.add(DiagnosticsProperty<TextTheme>('textTheme', textTheme));
     properties.add(DiagnosticsProperty<TextTheme>('primaryTextTheme', primaryTextTheme));

packages/flutter/lib/src/painting/box_decoration.dart

@@ -10,6 +10,7 @@ import 'basic_types.dart';
 import 'border_radius.dart';
 import 'box_border.dart';
 import 'box_shadow.dart';
+import 'colors.dart';
 import 'decoration.dart';
 import 'decoration_image.dart';
 import 'edge_insets.dart';
@@ -319,7 +320,7 @@ class BoxDecoration extends Decoration {
       ..defaultDiagnosticsTreeStyle = DiagnosticsTreeStyle.whitespace
       ..emptyBodyDescription = '<no decorations specified>';
 
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
     properties.add(DiagnosticsProperty<DecorationImage>('image', image, defaultValue: null));
     properties.add(DiagnosticsProperty<BoxBorder>('border', border, defaultValue: null));
     properties.add(DiagnosticsProperty<BorderRadiusGeometry>('borderRadius', borderRadius, defaultValue: null));

packages/flutter/lib/src/painting/colors.dart

@@ -460,3 +460,40 @@ class ColorSwatch<T> extends Color {
   @override
   String toString() => '$runtimeType(primary value: ${super.toString()})';
 }
+
+/// [DiagnosticsProperty] that has an [Color] as value.
+class ColorProperty extends DiagnosticsProperty<Color> {
+  /// Create a diagnostics property for [Color].
+  ///
+  /// The [showName], [style], and [level] arguments must not be null.
+  ColorProperty(
+    String name,
+    Color value, {
+      bool showName = true,
+      Object defaultValue = kNoDefaultValue,
+      DiagnosticsTreeStyle style = DiagnosticsTreeStyle.singleLine,
+      DiagnosticLevel level = DiagnosticLevel.info,
+  }) : assert(showName != null),
+       assert(style != null),
+       assert(level != null),
+       super(name, value,
+         defaultValue: defaultValue,
+         showName: showName,
+         style: style,
+         level: level,
+       );
+
+  @override
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
+    final Map<String, Object> json = super.toJsonMap(delegate);
+    if (value != null) {
+      json['valueProperties'] = <String, Object>{
+        'red': value.red,
+        'green': value.green,
+        'blue': value.blue,
+        'alpha': value.alpha,
+      };
+    }
+    return json;
+  }
+}

packages/flutter/lib/src/painting/shape_decoration.dart

@@ -10,6 +10,7 @@ import 'box_border.dart';
 import 'box_decoration.dart';
 import 'box_shadow.dart';
 import 'circle_border.dart';
+import 'colors.dart';
 import 'decoration.dart';
 import 'decoration_image.dart';
 import 'edge_insets.dart';
@@ -262,7 +263,7 @@ class ShapeDecoration extends Decoration {
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
     properties.defaultDiagnosticsTreeStyle = DiagnosticsTreeStyle.whitespace;
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
     properties.add(DiagnosticsProperty<Gradient>('gradient', gradient, defaultValue: null));
     properties.add(DiagnosticsProperty<DecorationImage>('image', image, defaultValue: null));
     properties.add(IterableProperty<BoxShadow>('shadows', shadows, defaultValue: null, style: DiagnosticsTreeStyle.whitespace));

packages/flutter/lib/src/painting/text_style.dart

@@ -7,6 +7,7 @@ import 'dart:ui' as ui show ParagraphStyle, TextStyle, StrutStyle, lerpDouble, S
 import 'package:flutter/foundation.dart';
 
 import 'basic_types.dart';
+import 'colors.dart';
 import 'strut_style.dart';
 
 const String _kDefaultDebugLabel = 'unknown';
@@ -1091,8 +1092,8 @@ class TextStyle extends Diagnosticable {
     if (debugLabel != null)
       properties.add(MessageProperty('${prefix}debugLabel', debugLabel));
     final List<DiagnosticsNode> styles = <DiagnosticsNode>[];
-    styles.add(DiagnosticsProperty<Color>('${prefix}color', color, defaultValue: null));
-    styles.add(DiagnosticsProperty<Color>('${prefix}backgroundColor', backgroundColor, defaultValue: null));
+    styles.add(ColorProperty('${prefix}color', color, defaultValue: null));
+    styles.add(ColorProperty('${prefix}backgroundColor', backgroundColor, defaultValue: null));
     styles.add(StringProperty('${prefix}family', fontFamily, defaultValue: null, quoted: false));
     styles.add(IterableProperty<String>('${prefix}familyFallback', fontFamilyFallback, defaultValue: null));
     styles.add(DoubleProperty('${prefix}size', fontSize, defaultValue: null));
@@ -1124,7 +1125,7 @@ class TextStyle extends Diagnosticable {
 
       // Hide decorationColor from the default text view as it is shown in the
       // terse decoration summary as well.
-      styles.add(DiagnosticsProperty<Color>('${prefix}decorationColor', decorationColor, defaultValue: null, level: DiagnosticLevel.fine));
+      styles.add(ColorProperty('${prefix}decorationColor', decorationColor, defaultValue: null, level: DiagnosticLevel.fine));
 
       if (decorationColor != null)
         decorationDescription.add('$decorationColor');

packages/flutter/lib/src/rendering/editable.dart

@@ -1780,12 +1780,12 @@ class RenderEditable extends RenderBox {
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
-    properties.add(DiagnosticsProperty<Color>('cursorColor', cursorColor));
+    properties.add(ColorProperty('cursorColor', cursorColor));
     properties.add(DiagnosticsProperty<ValueNotifier<bool>>('showCursor', showCursor));
     properties.add(IntProperty('maxLines', maxLines));
     properties.add(IntProperty('minLines', minLines));
     properties.add(DiagnosticsProperty<bool>('expands', expands, defaultValue: false));
-    properties.add(DiagnosticsProperty<Color>('selectionColor', selectionColor));
+    properties.add(ColorProperty('selectionColor', selectionColor));
     properties.add(DoubleProperty('textScaleFactor', textScaleFactor));
     properties.add(DiagnosticsProperty<Locale>('locale', locale, defaultValue: null));
     properties.add(DiagnosticsProperty<TextSelection>('selection', selection));

packages/flutter/lib/src/rendering/image.dart

@@ -377,7 +377,7 @@ class RenderImage extends RenderBox {
     properties.add(DoubleProperty('width', width, defaultValue: null));
     properties.add(DoubleProperty('height', height, defaultValue: null));
     properties.add(DoubleProperty('scale', scale, defaultValue: 1.0));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
     properties.add(EnumProperty<BlendMode>('colorBlendMode', colorBlendMode, defaultValue: null));
     properties.add(EnumProperty<BoxFit>('fit', fit, defaultValue: null));
     properties.add(DiagnosticsProperty<AlignmentGeometry>('alignment', alignment, defaultValue: null));

packages/flutter/lib/src/rendering/layer.dart

@@ -1607,7 +1607,7 @@ class PhysicalModelLayer extends ContainerLayer {
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
     properties.add(DoubleProperty('elevation', elevation));
-    properties.add(DiagnosticsProperty<Color>('color', color));
+    properties.add(ColorProperty('color', color));
   }
 }
 

packages/flutter/lib/src/rendering/proxy_box.dart

@@ -1592,8 +1592,8 @@ abstract class _RenderPhysicalModelBase<T> extends _RenderCustomClip<T> {
   void debugFillProperties(DiagnosticPropertiesBuilder description) {
     super.debugFillProperties(description);
     description.add(DoubleProperty('elevation', elevation));
-    description.add(DiagnosticsProperty<Color>('color', color));
-    description.add(DiagnosticsProperty<Color>('shadowColor', color));
+    description.add(ColorProperty('color', color));
+    description.add(ColorProperty('shadowColor', color));
   }
 }
 

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

@@ -322,7 +322,7 @@ class Banner extends StatelessWidget {
     properties.add(EnumProperty<TextDirection>('textDirection', textDirection, defaultValue: null));
     properties.add(EnumProperty<BannerLocation>('location', location));
     properties.add(EnumProperty<TextDirection>('layoutDirection', layoutDirection, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('color', color, showName: false));
+    properties.add(ColorProperty('color', color, showName: false));
     textStyle?.debugFillProperties(properties, prefix: 'text ');
   }
 }

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

@@ -907,8 +907,8 @@ class PhysicalModel extends SingleChildRenderObjectWidget {
     properties.add(EnumProperty<BoxShape>('shape', shape));
     properties.add(DiagnosticsProperty<BorderRadius>('borderRadius', borderRadius));
     properties.add(DoubleProperty('elevation', elevation));
-    properties.add(DiagnosticsProperty<Color>('color', color));
-    properties.add(DiagnosticsProperty<Color>('shadowColor', shadowColor));
+    properties.add(ColorProperty('color', color));
+    properties.add(ColorProperty('shadowColor', shadowColor));
   }
 }
 
@@ -994,8 +994,8 @@ class PhysicalShape extends SingleChildRenderObjectWidget {
     super.debugFillProperties(properties);
     properties.add(DiagnosticsProperty<CustomClipper<Path>>('clipper', clipper));
     properties.add(DoubleProperty('elevation', elevation));
-    properties.add(DiagnosticsProperty<Color>('color', color));
-    properties.add(DiagnosticsProperty<Color>('shadowColor', shadowColor));
+    properties.add(ColorProperty('color', color));
+    properties.add(ColorProperty('shadowColor', shadowColor));
   }
 }
 
@@ -5257,7 +5257,7 @@ class RawImage extends LeafRenderObjectWidget {
     properties.add(DoubleProperty('width', width, defaultValue: null));
     properties.add(DoubleProperty('height', height, defaultValue: null));
     properties.add(DoubleProperty('scale', scale, defaultValue: 1.0));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
     properties.add(EnumProperty<BlendMode>('colorBlendMode', colorBlendMode, defaultValue: null));
     properties.add(EnumProperty<BoxFit>('fit', fit, defaultValue: null));
     properties.add(DiagnosticsProperty<AlignmentGeometry>('alignment', alignment, defaultValue: null));

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

@@ -3520,6 +3520,15 @@ abstract class Element extends DiagnosticableTree implements BuildContext {
     return widget != null ? '${widget.toStringShort()}' : '[$runtimeType]';
   }
 
+  @override
+  DiagnosticsNode toDiagnosticsNode({ String name, DiagnosticsTreeStyle style }) {
+    return _ElementDiagnosticableTreeNode(
+      name: name,
+      value: this,
+      style: style,
+    );
+  }
+
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
@@ -3670,6 +3679,30 @@ abstract class Element extends DiagnosticableTree implements BuildContext {
   void performRebuild();
 }
 
+class _ElementDiagnosticableTreeNode extends DiagnosticableTreeNode {
+  _ElementDiagnosticableTreeNode({
+    String name,
+    @required Element value,
+    @required DiagnosticsTreeStyle style,
+    this.stateful = false,
+  }) : super(
+    name: name,
+    value: value,
+    style: style,
+  );
+
+  final bool stateful;
+
+  @override
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
+    final Map<String, Object> json = super.toJsonMap(delegate);
+    final Element element = value;
+    json['widgetRuntimeType'] = element.widget?.runtimeType?.toString();
+    json['stateful'] = stateful;
+    return json;
+  }
+}
+
 /// Signature for the constructor that is called when an error occurs while
 /// building a widget.
 ///
@@ -4075,6 +4108,16 @@ class StatefulElement extends ComponentElement {
     _state.didChangeDependencies();
   }
 
+  @override
+  DiagnosticsNode toDiagnosticsNode({ String name, DiagnosticsTreeStyle style }) {
+    return _ElementDiagnosticableTreeNode(
+      name: name,
+      value: this,
+      style: style,
+      stateful: true,
+    );
+  }
+
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);

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

@@ -198,8 +198,8 @@ class Icon extends StatelessWidget {
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
-    properties.add(DiagnosticsProperty<IconData>('icon', icon, ifNull: '<empty>', showName: false));
+    properties.add(IconDataProperty('icon', icon, ifNull: '<empty>', showName: false));
     properties.add(DoubleProperty('size', size, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
   }
 }

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

@@ -66,3 +66,37 @@ class IconData {
   @override
   String toString() => 'IconData(U+${codePoint.toRadixString(16).toUpperCase().padLeft(5, '0')})';
 }
+
+/// [DiagnosticsProperty] that has an [IconData] as value.
+class IconDataProperty extends DiagnosticsProperty<IconData> {
+  /// Create a diagnostics property for [IconData].
+  ///
+  /// The [showName], [style], and [level] arguments must not be null.
+  IconDataProperty(
+    String name,
+    IconData value, {
+      String ifNull,
+      bool showName = true,
+      DiagnosticsTreeStyle style = DiagnosticsTreeStyle.singleLine,
+      DiagnosticLevel level = DiagnosticLevel.info,
+  }) : assert(showName != null),
+       assert(style != null),
+       assert(level != null),
+       super(name, value,
+         showName: showName,
+         ifNull: ifNull,
+         style: style,
+         level: level,
+       );
+
+  @override
+  Map<String, Object> toJsonMap(DiagnosticsSerializationDelegate delegate) {
+    final Map<String, Object> json = super.toJsonMap(delegate);
+    if (value != null) {
+      json['valueProperties'] = <String, Object>{
+        'codePoint': value.codePoint,
+      };
+    }
+    return json;
+  }
+}

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

@@ -6,6 +6,7 @@ import 'dart:ui' show Color, hashValues;
 import 'dart:ui' as ui show lerpDouble;
 
 import 'package:flutter/foundation.dart';
+import 'package:flutter/painting.dart';
 
 /// Defines the color, opacity, and size of icons.
 ///
@@ -94,7 +95,7 @@ class IconThemeData extends Diagnosticable {
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
     properties.add(DoubleProperty('opacity', opacity, defaultValue: null));
     properties.add(DoubleProperty('size', size, defaultValue: null));
   }

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

@@ -837,7 +837,7 @@ class Image extends StatefulWidget {
     properties.add(DiagnosticsProperty<Function>('loadingBuilder', loadingBuilder));
     properties.add(DoubleProperty('width', width, defaultValue: null));
     properties.add(DoubleProperty('height', height, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
     properties.add(EnumProperty<BlendMode>('colorBlendMode', colorBlendMode, defaultValue: null));
     properties.add(EnumProperty<BoxFit>('fit', fit, defaultValue: null));
     properties.add(DiagnosticsProperty<AlignmentGeometry>('alignment', alignment, defaultValue: null));

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

@@ -102,6 +102,6 @@ class ImageIcon extends StatelessWidget {
     super.debugFillProperties(properties);
     properties.add(DiagnosticsProperty<ImageProvider>('image', image, ifNull: '<empty>', showName: false));
     properties.add(DoubleProperty('size', size, defaultValue: null));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
   }
 }

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

@@ -1441,9 +1441,9 @@ class AnimatedPhysicalModel extends ImplicitlyAnimatedWidget {
     properties.add(EnumProperty<BoxShape>('shape', shape));
     properties.add(DiagnosticsProperty<BorderRadius>('borderRadius', borderRadius));
     properties.add(DoubleProperty('elevation', elevation));
-    properties.add(DiagnosticsProperty<Color>('color', color));
+    properties.add(ColorProperty('color', color));
     properties.add(DiagnosticsProperty<bool>('animateColor', animateColor));
-    properties.add(DiagnosticsProperty<Color>('shadowColor', shadowColor));
+    properties.add(ColorProperty('shadowColor', shadowColor));
     properties.add(DiagnosticsProperty<bool>('animateShadowColor', animateShadowColor));
   }
 }

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

@@ -124,7 +124,7 @@ class GlowingOverscrollIndicator extends StatefulWidget {
       showDescription = 'neither side (!)';
     }
     properties.add(MessageProperty('show', showDescription));
-    properties.add(DiagnosticsProperty<Color>('color', color, showName: false));
+    properties.add(ColorProperty('color', color, showName: false));
   }
 }
 

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

@@ -53,6 +53,6 @@ class Title extends StatelessWidget {
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
     properties.add(StringProperty('title', title, defaultValue: ''));
-    properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
+    properties.add(ColorProperty('color', color, defaultValue: null));
   }
 }

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

@@ -33,7 +33,6 @@ import 'binding.dart';
 import 'debug.dart';
 import 'framework.dart';
 import 'gesture_detector.dart';
-import 'icon_data.dart';
 
 /// Signature for the builder callback used by
 /// [WidgetInspector.selectButtonBuilder].
@@ -677,60 +676,6 @@ class _InspectorReferenceData {
   int count = 1;
 }
 
-/// Configuration controlling how [DiagnosticsNode] objects are serialized to
-/// JSON mainly focused on if and how children are included in the JSON.
-class _SerializeConfig {
-  _SerializeConfig({
-    this.groupName,
-    this.summaryTree = false,
-    this.subtreeDepth  = 1,
-    this.includeProperties = false,
-    this.expandPropertyValues = true,
-    this.maxDescendentsTruncatableNode = -1,
-  });
-
-  _SerializeConfig.merge(
-    _SerializeConfig base, {
-    int subtreeDepth,
-  }) : groupName = base.groupName,
-       summaryTree = base.summaryTree,
-       subtreeDepth = subtreeDepth ?? base.subtreeDepth,
-       includeProperties = base.includeProperties,
-       expandPropertyValues = base.expandPropertyValues,
-       maxDescendentsTruncatableNode = base.maxDescendentsTruncatableNode;
-
-  /// Optional object group name used to manage manage lifetimes of object
-  /// references in the returned JSON.
-  ///
-  /// A call to `ext.flutter.inspector.disposeGroup` is required before objects
-  /// in the tree are garbage collected unless [groupName] is null in
-  /// which case no object references are included in the JSON payload.
-  final String groupName;
-
-  /// Whether to only include children that would exist in the summary tree.
-  final bool summaryTree;
-
-  /// How many levels of children to include in the JSON payload.
-  final int subtreeDepth;
-
-  /// Include information about properties in the JSON instead of requiring
-  /// a separate request to determine properties.
-  final bool includeProperties;
-
-  /// Expand children of properties that have values that are themselves
-  /// Diagnosticable objects.
-  final bool expandPropertyValues;
-
-  /// Whether to include object references to the [DiagnosticsNode] and
-  /// [DiagnosticsNode.value] objects in the JSON payload.
-  ///
-  /// If [interactive] is true, a call to `ext.flutter.inspector.disposeGroup`
-  /// is required before objects in the tree will ever be garbage collected.
-  bool get interactive => groupName != null;
-
-  final int maxDescendentsTruncatableNode;
-}
-
 // Production implementation of [WidgetInspectorService].
 class _WidgetInspectorService = Object with WidgetInspectorService;
 
@@ -966,12 +911,13 @@ mixin WidgetInspectorService {
   void _reportError(FlutterErrorDetails details) {
     postEvent('Flutter.Error', _nodeToJson(
       details.toDiagnosticsNode(),
-      _SerializeConfig(
+      _SerializationDelegate(
         groupName: _consoleObjectGroup,
         subtreeDepth: 5,
         includeProperties: true,
         expandPropertyValues: true,
         maxDescendentsTruncatableNode: 5,
+        service: this,
       ),
     ));
   }
@@ -1390,16 +1336,16 @@ mixin WidgetInspectorService {
 
     return path.map<Object>((_DiagnosticsPathNode node) => _pathNodeToJson(
       node,
-      _SerializeConfig(groupName: groupName),
+      _SerializationDelegate(groupName: groupName, service: this),
     )).toList();
   }
 
-  Map<String, Object> _pathNodeToJson(_DiagnosticsPathNode pathNode, _SerializeConfig config) {
+  Map<String, Object> _pathNodeToJson(_DiagnosticsPathNode pathNode, _SerializationDelegate delegate) {
     if (pathNode == null)
       return null;
     return <String, Object>{
-      'node': _nodeToJson(pathNode.node, config),
-      'children': _nodesToJson(pathNode.children, config, parent: pathNode.node),
+      'node': _nodeToJson(pathNode.node, delegate),
+      'children': _nodesToJson(pathNode.children, delegate, parent: pathNode.node),
       'childIndex': pathNode.childIndex,
     };
   }
@@ -1437,90 +1383,9 @@ mixin WidgetInspectorService {
 
   Map<String, Object> _nodeToJson(
     DiagnosticsNode node,
-    _SerializeConfig config,
+    _SerializationDelegate delegate,
   ) {
-    if (node == null)
-      return null;
-    final Map<String, Object> json = node.toJsonMap();
-
-    final Object value = node.value;
-    if (config.interactive) {
-      json['objectId'] = toId(node, config.groupName);
-      json['valueId'] = toId(value, config.groupName);
-    }
-
-    if (value  is Element) {
-      if (value is StatefulElement) {
-        json['stateful'] = true;
-      }
-      json['widgetRuntimeType'] = value.widget?.runtimeType.toString();
-    }
-
-    if (config.summaryTree) {
-      json['summaryTree'] = true;
-    }
-
-    final _Location creationLocation = _getCreationLocation(value);
-    bool createdByLocalProject = false;
-    if (creationLocation != null) {
-      json['locationId'] = _toLocationId(creationLocation);
-      json['creationLocation'] = creationLocation.toJsonMap();
-      if (_isLocalCreationLocation(creationLocation)) {
-        createdByLocalProject = true;
-        json['createdByLocalProject'] = true;
-      }
-    }
-
-    if (config.subtreeDepth > 0) {
-      json['children'] = _nodesToJson(_getChildrenHelper(node, config), config, parent: node);
-    }
-
-    if (config.includeProperties) {
-      final List<DiagnosticsNode> properties = node.getProperties();
-      if (properties.isEmpty && node is DiagnosticsProperty
-          && config.expandPropertyValues && value is Diagnosticable) {
-        // Special case to expand property values.
-        json['properties'] = _nodesToJson(
-          value.toDiagnosticsNode().getProperties().where(
-            (DiagnosticsNode node) => !node.isFiltered(DiagnosticLevel.info),
-          ),
-          _SerializeConfig(groupName: config.groupName,
-            subtreeDepth: 0,
-            expandPropertyValues: false,
-          ),
-          parent: node,
-        );
-      } else {
-        json['properties'] = _nodesToJson(
-          properties.where(
-                (DiagnosticsNode node) => !node.isFiltered(
-                createdByLocalProject ? DiagnosticLevel.fine : DiagnosticLevel
-                    .info),
-          ),
-          _SerializeConfig.merge(
-              config, subtreeDepth: math.max(0, config.subtreeDepth - 1)),
-          parent: node,
-        );
-      }
-    }
-
-    if (node is DiagnosticsProperty) {
-      // Add additional information about properties needed for graphical
-      // display of properties.
-      if (value is Color) {
-        json['valueProperties'] = <String, Object>{
-          'red': value.red,
-          'green': value.green,
-          'blue': value.blue,
-          'alpha': value.alpha,
-        };
-      } else if (value is IconData) {
-        json['valueProperties'] = <String, Object>{
-          'codePoint': value.codePoint,
-        };
-      }
-    }
-    return json;
+    return node?.toJsonMap(delegate);
   }
 
   bool _isValueCreatedByLocalProject(Object value) {
@@ -1560,7 +1425,7 @@ mixin WidgetInspectorService {
     return jsonString;
   }
 
-  List<DiagnosticsNode> _truncateNodes(Iterable<DiagnosticsNode> nodes, _SerializeConfig config) {
+  List<DiagnosticsNode> _truncateNodes(Iterable<DiagnosticsNode> nodes, int maxDescendentsTruncatableNode) {
     if (nodes.every((DiagnosticsNode node) => node.value is Element) && isWidgetCreationTracked()) {
       final List<DiagnosticsNode> localNodes = nodes.where((DiagnosticsNode node) =>
           _isValueCreatedByLocalProject(node.value)).toList();
@@ -1568,37 +1433,15 @@ mixin WidgetInspectorService {
         return localNodes;
       }
     }
-    return nodes.take(config.maxDescendentsTruncatableNode).toList();
+    return nodes.take(maxDescendentsTruncatableNode).toList();
   }
 
   List<Map<String, Object>> _nodesToJson(
     Iterable<DiagnosticsNode> nodes,
-    _SerializeConfig config, {
+    _SerializationDelegate delegate, {
     @required DiagnosticsNode parent,
   }) {
-    bool truncated = false;
-    if (nodes == null)
-      return <Map<String, Object>>[];
-    if (config.maxDescendentsTruncatableNode >= 0 && parent?.allowTruncate == true && nodes.length > config.maxDescendentsTruncatableNode) {
-      nodes = _truncateNodes(nodes, config)..add(DiagnosticsNode.message('...'));
-      truncated = true;
-    }
-    final List<Map<String, Object>> json = nodes.map<Map<String, Object>>(
-      (DiagnosticsNode node) {
-        // The tricky special case here is that when in the detailsTree,
-        // we keep subtreeDepth from going down to zero until we reach nodes
-        // that also exist in the summary tree. This ensures that every time
-        // you expand a node in the details tree, you expand the entire subtree
-        // up until you reach the next nodes shared with the summary tree.
-        return _nodeToJson(
-          node,
-          config.summaryTree || config.subtreeDepth > 1 || _shouldShowInSummaryTree(node) ?
-              _SerializeConfig.merge(config, subtreeDepth: config.subtreeDepth - 1) : config,
-        );
-      }).toList();
-    if (truncated)
-      json.last['truncated'] = true;
-    return json;
+    return DiagnosticsNode.toJsonList(nodes, parent, delegate);
   }
 
   /// Returns a JSON representation of the properties of the [DiagnosticsNode]
@@ -1610,7 +1453,7 @@ mixin WidgetInspectorService {
 
   List<Object> _getProperties(String diagnosticsNodeId, String groupName) {
     final DiagnosticsNode node = toObject(diagnosticsNodeId);
-    return _nodesToJson(node == null ? const <DiagnosticsNode>[] : node.getProperties(), _SerializeConfig(groupName: groupName), parent: node);
+    return _nodesToJson(node == null ? const <DiagnosticsNode>[] : node.getProperties(), _SerializationDelegate(groupName: groupName, service: this), parent: node);
   }
 
   /// Returns a JSON representation of the children of the [DiagnosticsNode]
@@ -1621,8 +1464,8 @@ mixin WidgetInspectorService {
 
   List<Object> _getChildren(String diagnosticsNodeId, String groupName) {
     final DiagnosticsNode node = toObject(diagnosticsNodeId);
-    final _SerializeConfig config = _SerializeConfig(groupName: groupName);
-    return _nodesToJson(node == null ? const <DiagnosticsNode>[] : _getChildrenHelper(node, config), config, parent: node);
+    final _SerializationDelegate delegate = _SerializationDelegate(groupName: groupName, service: this);
+    return _nodesToJson(node == null ? const <DiagnosticsNode>[] : _getChildrenFiltered(node, delegate), delegate, parent: node);
   }
 
   /// Returns a JSON representation of the children of the [DiagnosticsNode]
@@ -1643,8 +1486,8 @@ mixin WidgetInspectorService {
 
   List<Object> _getChildrenSummaryTree(String diagnosticsNodeId, String groupName) {
     final DiagnosticsNode node = toObject(diagnosticsNodeId);
-    final _SerializeConfig config = _SerializeConfig(groupName: groupName, summaryTree: true);
-    return _nodesToJson(node == null ? const <DiagnosticsNode>[] : _getChildrenHelper(node, config), config, parent: node);
+    final _SerializationDelegate delegate = _SerializationDelegate(groupName: groupName, summaryTree: true, service: this);
+    return _nodesToJson(node == null ? const <DiagnosticsNode>[] : _getChildrenFiltered(node, delegate), delegate, parent: node);
   }
 
   /// Returns a JSON representation of the children of the [DiagnosticsNode]
@@ -1660,12 +1503,8 @@ mixin WidgetInspectorService {
   List<Object> _getChildrenDetailsSubtree(String diagnosticsNodeId, String groupName) {
     final DiagnosticsNode node = toObject(diagnosticsNodeId);
     // With this value of minDepth we only expand one extra level of important nodes.
-    final _SerializeConfig config = _SerializeConfig(groupName: groupName, subtreeDepth: 1,  includeProperties: true);
-    return _nodesToJson(node == null ? const <DiagnosticsNode>[] : _getChildrenHelper(node, config), config, parent: node);
-  }
-
-  List<DiagnosticsNode> _getChildrenHelper(DiagnosticsNode node, _SerializeConfig config) {
-    return _getChildrenFiltered(node, config).toList();
+    final _SerializationDelegate delegate = _SerializationDelegate(groupName: groupName, subtreeDepth: 1, includeProperties: true, service: this);
+    return _nodesToJson(node == null ? const <DiagnosticsNode>[] : _getChildrenFiltered(node, delegate), delegate, parent: node);
   }
 
   bool _shouldShowInSummaryTree(DiagnosticsNode node) {
@@ -1686,16 +1525,21 @@ mixin WidgetInspectorService {
 
   List<DiagnosticsNode> _getChildrenFiltered(
     DiagnosticsNode node,
-    _SerializeConfig config,
+    _SerializationDelegate delegate,
   ) {
-    final List<DiagnosticsNode> children = <DiagnosticsNode>[];
-    final List<DiagnosticsNode> rawChildren = node.getChildren();
+    return _filterChildren(node.getChildren(), delegate);
+  }
 
-    for (DiagnosticsNode child in rawChildren) {
-      if (!config.summaryTree || _shouldShowInSummaryTree(child)) {
+  List<DiagnosticsNode> _filterChildren(
+    List<DiagnosticsNode> nodes,
+    _SerializationDelegate delegate,
+  ) {
+    final List<DiagnosticsNode> children = <DiagnosticsNode>[];
+    for (DiagnosticsNode child in nodes) {
+      if (!delegate.summaryTree || _shouldShowInSummaryTree(child)) {
         children.add(child);
       } else {
-        children.addAll(_getChildrenFiltered(child, config));
+        children.addAll(_getChildrenFiltered(child, delegate));
       }
     }
     return children;
@@ -1708,7 +1552,7 @@ mixin WidgetInspectorService {
   }
 
   Map<String, Object> _getRootWidget(String groupName) {
-    return _nodeToJson(WidgetsBinding.instance?.renderViewElement?.toDiagnosticsNode(), _SerializeConfig(groupName: groupName));
+    return _nodeToJson(WidgetsBinding.instance?.renderViewElement?.toDiagnosticsNode(), _SerializationDelegate(groupName: groupName, service: this));
   }
 
   /// Returns a JSON representation of the [DiagnosticsNode] for the root
@@ -1720,7 +1564,7 @@ mixin WidgetInspectorService {
   Map<String, Object> _getRootWidgetSummaryTree(String groupName) {
     return _nodeToJson(
       WidgetsBinding.instance?.renderViewElement?.toDiagnosticsNode(),
-      _SerializeConfig(groupName: groupName, subtreeDepth: 1000000, summaryTree: true),
+      _SerializationDelegate(groupName: groupName, subtreeDepth: 1000000, summaryTree: true, service: this),
     );
   }
 
@@ -1732,7 +1576,7 @@ mixin WidgetInspectorService {
   }
 
   Map<String, Object> _getRootRenderObject(String groupName) {
-    return _nodeToJson(RendererBinding.instance?.renderView?.toDiagnosticsNode(), _SerializeConfig(groupName: groupName));
+    return _nodeToJson(RendererBinding.instance?.renderView?.toDiagnosticsNode(), _SerializationDelegate(groupName: groupName, service: this));
   }
 
   /// Returns a JSON representation of the subtree rooted at the
@@ -1754,11 +1598,12 @@ mixin WidgetInspectorService {
     }
     return _nodeToJson(
       root,
-      _SerializeConfig(
+      _SerializationDelegate(
         groupName: groupName,
         summaryTree: false,
         subtreeDepth: 2,  // TODO(jacobr): make subtreeDepth configurable.
         includeProperties: true,
+        service: this,
       ),
     );
   }
@@ -1777,7 +1622,7 @@ mixin WidgetInspectorService {
   Map<String, Object> _getSelectedRenderObject(String previousSelectionId, String groupName) {
     final DiagnosticsNode previousSelection = toObject(previousSelectionId);
     final RenderObject current = selection?.current;
-    return _nodeToJson(current == previousSelection?.value ? previousSelection : current?.toDiagnosticsNode(), _SerializeConfig(groupName: groupName));
+    return _nodeToJson(current == previousSelection?.value ? previousSelection : current?.toDiagnosticsNode(), _SerializationDelegate(groupName: groupName, service: this));
   }
 
   /// Returns a [DiagnosticsNode] representing the currently selected [Element].
@@ -1864,7 +1709,7 @@ mixin WidgetInspectorService {
   Map<String, Object> _getSelectedWidget(String previousSelectionId, String groupName) {
     final DiagnosticsNode previousSelection = toObject(previousSelectionId);
     final Element current = selection?.currentElement;
-    return _nodeToJson(current == previousSelection?.value ? previousSelection : current?.toDiagnosticsNode(), _SerializeConfig(groupName: groupName));
+    return _nodeToJson(current == previousSelection?.value ? previousSelection : current?.toDiagnosticsNode(), _SerializationDelegate(groupName: groupName, service: this));
   }
 
   /// Returns a [DiagnosticsNode] representing the currently selected [Element]
@@ -1895,7 +1740,7 @@ mixin WidgetInspectorService {
       }
       current = firstLocal;
     }
-    return _nodeToJson(current == previousSelection?.value ? previousSelection : current?.toDiagnosticsNode(), _SerializeConfig(groupName: groupName));
+    return _nodeToJson(current == previousSelection?.value ? previousSelection : current?.toDiagnosticsNode(), _SerializationDelegate(groupName: groupName, service: this));
   }
 
   /// Returns whether [Widget] creation locations are available.
@@ -2888,3 +2733,104 @@ int _toLocationId(_Location location) {
   _locationToId[location] = id;
   return id;
 }
+
+class _SerializationDelegate implements DiagnosticsSerializationDelegate {
+  _SerializationDelegate({
+    this.groupName,
+    this.summaryTree = false,
+    this.maxDescendentsTruncatableNode = -1,
+    this.expandPropertyValues = true,
+    this.subtreeDepth = 1,
+    this.includeProperties = false,
+    @required this.service,
+  });
+
+  final WidgetInspectorService service;
+  final String groupName;
+  final bool summaryTree;
+  final int maxDescendentsTruncatableNode;
+
+  @override
+  final bool includeProperties;
+
+  @override
+  final int subtreeDepth;
+
+  @override
+  final bool expandPropertyValues;
+
+  final List<DiagnosticsNode> _nodesCreatedByLocalProject = <DiagnosticsNode>[];
+
+  bool get interactive => groupName != null;
+
+  @override
+  Map<String, Object> additionalNodeProperties(DiagnosticsNode node) {
+    final Map<String, Object> result = <String, Object>{};
+    final Object value = node.value;
+    if (interactive) {
+      result['objectId'] = service.toId(node, groupName);
+      result['valueId'] = service.toId(value, groupName);
+    }
+    if (summaryTree) {
+      result['summaryTree'] = true;
+    }
+    final _Location creationLocation = _getCreationLocation(value);
+    if (creationLocation != null) {
+      result['locationId'] = _toLocationId(creationLocation);
+      result['creationLocation'] = creationLocation.toJsonMap();
+      if (service._isLocalCreationLocation(creationLocation)) {
+        _nodesCreatedByLocalProject.add(node);
+        result['createdByLocalProject'] = true;
+      }
+    }
+    return result;
+  }
+
+  @override
+  DiagnosticsSerializationDelegate delegateForNode(DiagnosticsNode node) {
+    // The tricky special case here is that when in the detailsTree,
+    // we keep subtreeDepth from going down to zero until we reach nodes
+    // that also exist in the summary tree. This ensures that every time
+    // you expand a node in the details tree, you expand the entire subtree
+    // up until you reach the next nodes shared with the summary tree.
+    return summaryTree || subtreeDepth > 1 || service._shouldShowInSummaryTree(node)
+        ? copyWith(subtreeDepth: subtreeDepth - 1)
+        : this;
+  }
+
+  @override
+  List<DiagnosticsNode> filterChildren(List<DiagnosticsNode> children, DiagnosticsNode owner) {
+    return service._filterChildren(children, this);
+  }
+
+  @override
+  List<DiagnosticsNode> filterProperties(List<DiagnosticsNode> properties, DiagnosticsNode owner) {
+    final bool createdByLocalProject = _nodesCreatedByLocalProject.contains(owner);
+    return properties.where((DiagnosticsNode node) {
+      return !node.isFiltered(createdByLocalProject ? DiagnosticLevel.fine : DiagnosticLevel.info);
+    }).toList();
+  }
+
+  @override
+  List<DiagnosticsNode> truncateNodesList(List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+    if (maxDescendentsTruncatableNode >= 0 &&
+        owner?.allowTruncate == true &&
+        nodes.length > maxDescendentsTruncatableNode) {
+      nodes = service._truncateNodes(nodes, maxDescendentsTruncatableNode);
+    }
+    return nodes;
+  }
+
+  @override
+  DiagnosticsSerializationDelegate copyWith({int subtreeDepth, bool includeProperties}) {
+    return _SerializationDelegate(
+      groupName: groupName,
+      summaryTree: summaryTree,
+      maxDescendentsTruncatableNode: maxDescendentsTruncatableNode,
+      expandPropertyValues: expandPropertyValues,
+      subtreeDepth: subtreeDepth ?? this.subtreeDepth,
+      includeProperties: includeProperties ?? this.includeProperties,
+      service: service,
+    );
+  }
+}

packages/flutter/test/foundation/diagnostics_json_test.dart

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  test('Element diagnostics json includes widgetRuntimeType', () async {
+    final Element element = _TestElement();
+
+    final Map<String, Object> json = element.toDiagnosticsNode().toJsonMap(const DiagnosticsSerializationDelegate());
+    expect(json['widgetRuntimeType'], 'Placeholder');
+    expect(json['stateful'], isFalse);
+  });
+
+  test('StatefulElement diganostics are stateful', () {
+    final Element element = StatefulElement(const Tooltip(message: 'foo'));
+
+    final Map<String, Object> json = element.toDiagnosticsNode().toJsonMap(const DiagnosticsSerializationDelegate());
+    expect(json['widgetRuntimeType'], 'Tooltip');
+    expect(json['stateful'], isTrue);
+  });
+
+  group('Serialization', () {
+    final TestTree testTree = TestTree(
+      properties: <DiagnosticsNode>[
+        StringProperty('stringProperty1', 'value1', quoted: false),
+        DoubleProperty('doubleProperty1', 42.5),
+        DoubleProperty('roundedProperty', 1.0 / 3.0),
+        StringProperty('DO_NOT_SHOW', 'DO_NOT_SHOW', level: DiagnosticLevel.hidden, quoted: false),
+        DiagnosticsProperty<Object>('DO_NOT_SHOW_NULL', null, defaultValue: null),
+        DiagnosticsProperty<Object>('nullProperty', null),
+        StringProperty('node_type', '<root node>', showName: false, quoted: false),
+      ],
+      children: <TestTree>[
+        TestTree(name: 'node A'),
+        TestTree(
+          name: 'node B',
+          properties: <DiagnosticsNode>[
+            StringProperty('p1', 'v1', quoted: false),
+            StringProperty('p2', 'v2', quoted: false),
+          ],
+          children: <TestTree>[
+            TestTree(name: 'node B1'),
+            TestTree(
+              name: 'node B2',
+              properties: <DiagnosticsNode>[StringProperty('property1', 'value1', quoted: false)],
+            ),
+            TestTree(
+              name: 'node B3',
+              properties: <DiagnosticsNode>[
+                StringProperty('node_type', '<leaf node>', showName: false, quoted: false),
+                IntProperty('foo', 42),
+              ],
+            ),
+          ],
+        ),
+        TestTree(
+          name: 'node C',
+          properties: <DiagnosticsNode>[
+            StringProperty('foo', 'multi\nline\nvalue!', quoted: false),
+          ],
+        ),
+      ],
+    );
+
+    test('default', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(const DiagnosticsSerializationDelegate());
+      expect(result.containsKey('properties'), isFalse);
+      expect(result.containsKey('children'), isFalse);
+    });
+
+    test('subtreeDepth 1', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(const DiagnosticsSerializationDelegate(subtreeDepth: 1));
+      expect(result.containsKey('properties'), isFalse);
+      final List<Map<String, Object>> children = result['children'];
+      expect(children[0].containsKey('children'), isFalse);
+      expect(children[1].containsKey('children'), isFalse);
+      expect(children[2].containsKey('children'), isFalse);
+    });
+
+    test('subtreeDepth 5', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(const DiagnosticsSerializationDelegate(subtreeDepth: 5));
+      expect(result.containsKey('properties'), isFalse);
+      final List<Map<String, Object>> children = result['children'];
+      expect(children[0]['children'], hasLength(0));
+      expect(children[1]['children'], hasLength(3));
+      expect(children[2]['children'], hasLength(0));
+    });
+
+    test('includeProperties', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(const DiagnosticsSerializationDelegate(includeProperties: true));
+      expect(result.containsKey('children'), isFalse);
+      expect(result['properties'], hasLength(7));
+    });
+
+    test('includeProperties with subtreedepth 1', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(const DiagnosticsSerializationDelegate(
+        includeProperties: true,
+        subtreeDepth: 1,
+      ));
+      expect(result['properties'], hasLength(7));
+      final List<Map<String, Object>> children = result['children'];
+      expect(children, hasLength(3));
+      expect(children[0]['properties'], hasLength(0));
+      expect(children[1]['properties'], hasLength(2));
+      expect(children[2]['properties'], hasLength(1));
+    });
+
+    test('additionalNodeProperties', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(const TestDiagnosticsSerializationDelegate(
+        includeProperties: true,
+        subtreeDepth: 1,
+        additionalNodePropertiesMap: <String, Object>{
+          'foo': true,
+        },
+      ));
+      expect(result['foo'], isTrue);
+      final List<Map<String, Object>> properties = result['properties'];
+      expect(properties, hasLength(7));
+      expect(properties.every((Map<String, Object> property) => property['foo'] == true), isTrue);
+
+      final List<Map<String, Object>> children = result['children'];
+      expect(children, hasLength(3));
+      expect(children.every((Map<String, Object> child) => child['foo'] == true), isTrue);
+    });
+
+    test('filterProperties - sublist', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(TestDiagnosticsSerializationDelegate(
+          includeProperties: true,
+          propertyFilter: (List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+            return nodes.whereType<StringProperty>().toList();
+          }
+      ));
+      final List<Map<String, Object>> properties = result['properties'];
+      expect(properties, hasLength(3));
+      expect(properties.every((Map<String, Object> property) => property['type'] == 'StringProperty'), isTrue);
+    });
+
+    test('filterProperties - replace', () {
+      bool replaced = false;
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(TestDiagnosticsSerializationDelegate(
+          includeProperties: true,
+          propertyFilter: (List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+            if (replaced) {
+              return nodes;
+            }
+            replaced = true;
+            return <DiagnosticsNode>[
+              StringProperty('foo', 'bar'),
+            ];
+          }
+      ));
+      final List<Map<String, Object>> properties = result['properties'];
+      expect(properties, hasLength(1));
+      expect(properties.single['name'], 'foo');
+    });
+
+    test('filterChildren - sublist', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(TestDiagnosticsSerializationDelegate(
+          subtreeDepth: 1,
+          childFilter: (List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+            return nodes.where((DiagnosticsNode node) => node.getProperties().isEmpty).toList();
+          }
+      ));
+      final List<Map<String, Object>> children = result['children'];
+      expect(children, hasLength(1));
+    });
+
+    test('filterChildren - replace', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(TestDiagnosticsSerializationDelegate(
+          subtreeDepth: 1,
+          childFilter: (List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+            final List<DiagnosticsNode> result = <DiagnosticsNode>[];
+            for (DiagnosticsNode node in nodes) {
+              result.addAll(node.getChildren());
+            }
+            return result;
+          }
+      ));
+      final List<Map<String, Object>> children = result['children'];
+      expect(children, hasLength(3));
+      expect(children.first['name'], 'child node B1');
+    });
+
+    test('nodeTruncator', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(TestDiagnosticsSerializationDelegate(
+          subtreeDepth: 5,
+          includeProperties: true,
+          nodeTruncator: (List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+            return nodes.take(2).toList();
+          }
+      ));
+      final List<Map<String, Object>> children = result['children'];
+      expect(children, hasLength(3));
+      expect(children.last['truncated'], isTrue);
+
+      final List<Map<String, Object>> properties = result['properties'];
+      expect(properties, hasLength(3));
+      expect(properties.last['truncated'], isTrue);
+    });
+
+    test('delegateForAddingNodes', () {
+      final Map<String, Object> result = testTree.toDiagnosticsNode().toJsonMap(TestDiagnosticsSerializationDelegate(
+          subtreeDepth: 5,
+          includeProperties: true,
+          nodeDelegator: (DiagnosticsNode node, DiagnosticsSerializationDelegate delegate) {
+            return delegate.copyWith(includeProperties: false);
+          }
+      ));
+      final List<Map<String, Object>> properties = result['properties'];
+      expect(properties, hasLength(7));
+      expect(properties.every((Map<String, Object> property) => !property.containsKey('properties')), isTrue);
+
+      final List<Map<String, Object>> children = result['children'];
+      expect(children, hasLength(3));
+      expect(children.every((Map<String, Object> child) => !child.containsKey('properties')), isTrue);
+    });
+  });
+}
+
+class _TestElement extends Element {
+  _TestElement() : super(const Placeholder());
+
+  @override
+  void forgetChild(Element child) {
+    // Intentionally left empty.
+  }
+
+  @override
+  void performRebuild() {
+    // Intentionally left empty.
+  }
+}
+
+class TestTree extends Object with DiagnosticableTreeMixin {
+  TestTree({
+    this.name,
+    this.style,
+    this.children = const <TestTree>[],
+    this.properties = const <DiagnosticsNode>[],
+  });
+
+  final String name;
+  final List<TestTree> children;
+  final List<DiagnosticsNode> properties;
+  final DiagnosticsTreeStyle style;
+
+  @override
+  List<DiagnosticsNode> debugDescribeChildren() {
+    final List<DiagnosticsNode> children = <DiagnosticsNode>[];
+    for (TestTree child in this.children) {
+      children.add(child.toDiagnosticsNode(
+        name: 'child ${child.name}',
+        style: child.style,
+      ));
+    }
+    return children;
+  }
+
+  @override
+  void debugFillProperties(DiagnosticPropertiesBuilder properties) {
+    super.debugFillProperties(properties);
+    if (style != null)
+      properties.defaultDiagnosticsTreeStyle = style;
+
+    this.properties.forEach(properties.add);
+  }
+}
+
+class TestDiagnosticsSerializationDelegate implements DiagnosticsSerializationDelegate {
+  const TestDiagnosticsSerializationDelegate({
+    this.includeProperties = false,
+    this.subtreeDepth = 0,
+    this.additionalNodePropertiesMap = const <String, Object>{},
+    this.childFilter,
+    this.propertyFilter,
+    this.nodeTruncator,
+    this.nodeDelegator,
+  });
+
+  final Map<String, Object> additionalNodePropertiesMap;
+  final Function childFilter;
+  final Function propertyFilter;
+  final Function nodeTruncator;
+  final Function nodeDelegator;
+
+  @override
+  Map<String, Object> additionalNodeProperties(DiagnosticsNode node) {
+    return additionalNodePropertiesMap;
+  }
+
+  @override
+  DiagnosticsSerializationDelegate delegateForNode(DiagnosticsNode node) {
+    if (nodeDelegator != null) {
+      return nodeDelegator(node, this);
+    }
+    return subtreeDepth > 0 ? copyWith(subtreeDepth: subtreeDepth - 1) : this;
+  }
+
+  @override
+  bool get expandPropertyValues => false;
+
+  @override
+  List<DiagnosticsNode> filterChildren(List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+    return childFilter != null ? childFilter(nodes, owner) : nodes;
+  }
+
+  @override
+  List<DiagnosticsNode> filterProperties(List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+    return propertyFilter != null ? propertyFilter(nodes, owner) : nodes;
+  }
+
+  @override
+  final bool includeProperties;
+
+  @override
+  final int subtreeDepth;
+
+  @override
+  List<DiagnosticsNode> truncateNodesList(List<DiagnosticsNode> nodes, DiagnosticsNode owner) {
+    return nodeTruncator != null ? nodeTruncator(nodes, owner) : nodes;
+  }
+
+  @override
+  DiagnosticsSerializationDelegate copyWith({int subtreeDepth, bool includeProperties}) {
+    return TestDiagnosticsSerializationDelegate(
+      includeProperties: includeProperties ?? this.includeProperties,
+      subtreeDepth: subtreeDepth ?? this.subtreeDepth,
+      additionalNodePropertiesMap: additionalNodePropertiesMap,
+      childFilter: childFilter,
+      propertyFilter: propertyFilter,
+      nodeTruncator: nodeTruncator,
+      nodeDelegator: nodeDelegator,
+    );
+  }
+}

packages/flutter/test/foundation/diagnostics_test.dart

@@ -52,7 +52,7 @@ enum ExampleEnum {
 /// Encode and decode to JSON to make sure all objects in the JSON for the
 /// [DiagnosticsNode] are valid JSON.
 Map<String, Object> simulateJsonSerialization(DiagnosticsNode node) {
-  return json.decode(json.encode(node.toJsonMap()));
+  return json.decode(json.encode(node.toJsonMap(const DiagnosticsSerializationDelegate())));
 }
 
 void validateNodeJsonSerialization(DiagnosticsNode node) {

packages/flutter/test/material/slider_theme_test.dart

@@ -68,7 +68,6 @@ void main() {
     expect(description, <String>[
       'trackHeight: 7.0',
       'activeTrackColor: Color(0xff000001)',
-      'activeTrackColor: Color(0xff000001)',
       'inactiveTrackColor: Color(0xff000002)',
       'disabledActiveTrackColor: Color(0xff000003)',
       'disabledInactiveTrackColor: Color(0xff000004)',

packages/flutter/test/painting/colors_test.dart

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/painting.dart';
 import 'package:flutter_test/flutter_test.dart';
 
@@ -424,4 +425,17 @@ void main() {
     expect(greens1['2259 C'], const Color(0xFF027223));
     expect(greens1.value, 0xFF027223);
   });
+
+  test('ColorDiagnosticsProperty includes valueProperties in JSON', () {
+    ColorProperty property = ColorProperty('foo', const Color.fromARGB(10, 20, 30, 40));
+    final Map<String, Object> valueProperties = property.toJsonMap(const DiagnosticsSerializationDelegate())['valueProperties'];
+    expect(valueProperties['alpha'], 10);
+    expect(valueProperties['red'], 20);
+    expect(valueProperties['green'], 30);
+    expect(valueProperties['blue'], 40);
+
+    property = ColorProperty('foo', null);
+    final Map<String, Object> json = property.toJsonMap(const DiagnosticsSerializationDelegate());
+    expect(json.containsKey('valueProperties'), isFalse);
+  });
 }

packages/flutter/test/widgets/icon_data_test.dart

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  test('IconDataDiagnosticsProperty includes valueProperties in JSON', () {
+    IconDataProperty property = IconDataProperty('foo', const IconData(101010));
+    final Map<String, Object> valueProperties = property.toJsonMap(const DiagnosticsSerializationDelegate())['valueProperties'];
+    print(valueProperties);
+    expect(valueProperties['codePoint'], 101010);
+
+    property = IconDataProperty('foo', null);
+    final Map<String, Object> json = property.toJsonMap(const DiagnosticsSerializationDelegate());
+    expect(json.containsKey('valueProperties'), isFalse);
+  });
+}

packages/flutter/test/widgets/widget_inspector_test.dart

@@ -2361,6 +2361,63 @@ class TestWidgetInspectorService extends Object with WidgetInspectorService {
       expect(box1.localToGlobal(Offset.zero), equals(position1));
       expect(box2.localToGlobal(Offset.zero), equals(position2));
     }, skip: isBrowser);
+
+    testWidgets('getChildrenDetailsSubtree', (WidgetTester tester) async {
+      await tester.pumpWidget(
+        MaterialApp(
+          title: 'Hello, World',
+          theme: ThemeData(
+            primarySwatch: Colors.blue,
+          ),
+          home: Scaffold(
+            appBar: AppBar(
+              title: const Text('Hello, World'),
+            ),
+            body: const Center(
+              child: Text('Hello, World!'),
+            ),
+          ),
+        ),
+      );
+
+      // Figure out the pubRootDirectory
+      final Map<String, Object> jsonObject = await service.testExtension(
+          'getSelectedWidget',
+          <String, String>{'arg': null, 'objectGroup': 'my-group'},
+      );
+      final Map<String, Object> creationLocation =
+      jsonObject['creationLocation'];
+      expect(creationLocation, isNotNull);
+      final String file = creationLocation['file'];
+      expect(file, endsWith('widget_inspector_test.dart'));
+      final List<String> segments = Uri.parse(file).pathSegments;
+      // Strip a couple subdirectories away to generate a plausible pub rootdirectory.
+      final String pubRootTest = '/' + segments.take(segments.length - 2).join('/');
+      service.setPubRootDirectories(<String>[pubRootTest]);
+
+      final String summary = service.getRootWidgetSummaryTree('foo1');
+      final List<dynamic> childrenOfRoot = json.decode(summary)['children'];
+      final List<dynamic> childrenOfMaterialApp = childrenOfRoot.first['children'];
+      final Map<String, Object> scaffold = childrenOfMaterialApp.first;
+      expect(scaffold['description'], 'Scaffold');
+      final String objectId = scaffold['objectId'];
+      final String details = service.getDetailsSubtree(objectId, 'foo2');
+      final List<dynamic> detailedChildren = json.decode(details)['children'];
+
+      final List<Map<String, Object>> appBars = <Map<String, Object>>[];
+      void visitChildren(List<dynamic> children) {
+        for (Map<String, Object> child in children) {
+          if (child['description'] == 'AppBar') {
+            appBars.add(child);
+          }
+          if (child.containsKey('children')) {
+            visitChildren(child['children']);
+          }
+        }
+      }
+      visitChildren(detailedChildren);
+      expect(appBars.single.containsKey('children'), isFalse);
+    }, skip: !WidgetInspectorService.instance.isWidgetCreationTracked()); // Test requires --track-widget-creation flag.
   }
 }