Version 3.1.0-324.0.dev

Merge f06a1d5 into dev

pkg/analyzer/lib/src/dart/element/class_hierarchy.dart

@@ -5,6 +5,7 @@
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/element/element.dart';
+import 'package:analyzer/src/dart/element/extensions.dart';
 import 'package:analyzer/src/dart/element/type_algebra.dart';
 import 'package:analyzer/src/dart/element/type_system.dart';
 import 'package:analyzer/src/utilities/extensions/collection.dart';
@@ -21,6 +22,7 @@ class ClassHierarchy {
   }
 
   void remove(InterfaceElement element) {
+    assert(!element.isAugmentation);
     _map.remove(element);
   }
 
@@ -32,14 +34,7 @@ class ClassHierarchy {
   }
 
   _Hierarchy _getHierarchy(InterfaceElement element) {
-    if (element.isAugmentation) {
-      throw StateError('Expected a declaration, not augmentations.');
-    }
-
-    final augmented = element.augmented;
-    if (augmented == null) {
-      throw StateError('Declarations always have augmented state.');
-    }
+    final augmented = element.augmentedOfDeclaration;
 
     var hierarchy = _map[element];
     if (hierarchy != null) {

pkg/analyzer/lib/src/dart/element/element.dart

@@ -2615,9 +2615,9 @@ class EnumElementImpl extends InterfaceElementImpl implements EnumElement {
   EnumElementImpl(super.name, super.offset);
 
   @override
-  Never get augmentation {
+  EnumElementImpl? get augmentation {
     // TODO(scheglov) implement
-    throw UnimplementedError();
+    return null;
   }
 
   @override
@@ -3521,6 +3521,9 @@ abstract class InterfaceElementImpl extends NamedInstanceElementImpl
     return library.session.classHierarchy.implementedInterfaces(this);
   }
 
+  @override
+  InterfaceElementImpl? get augmentation;
+
   @override
   InterfaceElementImpl? get augmentationTarget;
 
@@ -3633,6 +3636,15 @@ abstract class InterfaceElementImpl extends NamedInstanceElementImpl
     _typeParameterElements = typeParameters;
   }
 
+  /// This element and all its augmentations, in order.
+  Iterable<InterfaceElementImpl> get withAugmentations sync* {
+    InterfaceElementImpl? current = this;
+    while (current != null) {
+      yield current;
+      current = current.augmentation;
+    }
+  }
+
   @override
   FieldElement? getField(String name) {
     return fields.firstWhereOrNull((fieldElement) => name == fieldElement.name);

pkg/analyzer/lib/src/dart/element/extensions.dart

@@ -116,6 +116,22 @@ extension ExecutableElementExtensionQuestion on ExecutableElement? {
   }
 }
 
+extension InterfaceElementExtension on InterfaceElement {
+  /// The result of applying augmentations.
+  ///
+  /// The target must be a declaration, not an augmentation.
+  /// This getter will throw, if this is not the case.
+  AugmentedInterfaceElement get augmentedOfDeclaration {
+    if (isAugmentation) {
+      throw StateError(
+        'The target must be a declaration, not an augmentation.',
+      );
+    }
+    // This is safe because declarations always have it.
+    return augmented!;
+  }
+}
+
 extension ParameterElementExtensions on ParameterElement {
   /// Return [ParameterElement] with the specified properties replaced.
   ParameterElement copyWith({

pkg/analyzer/lib/src/dart/element/type.dart

@@ -477,6 +477,11 @@ class InterfaceTypeImpl extends TypeImpl implements InterfaceType {
     required this.nullabilitySuffix,
     super.alias,
   }) {
+    if (element.isAugmentation) {
+      throw ArgumentError(
+        'InterfaceType(s) can only be created for declarations',
+      );
+    }
     var typeParameters = element.typeParameters;
     if (typeArguments.length != typeParameters.length) {
       throw ArgumentError(

pkg/analyzer/lib/src/summary2/detach_nodes.dart

@@ -60,6 +60,14 @@ class _Visitor extends GeneralizingElementVisitor<void> {
     super.visitElement(element);
   }
 
+  @override
+  void visitEnumElement(EnumElement element) {
+    if (element is EnumElementImpl) {
+      element.mixinInferenceCallback = null;
+    }
+    super.visitEnumElement(element);
+  }
+
   @override
   void visitMixinElement(MixinElement element) {
     if (element is MixinElementImpl) {