Elements. Use more TypeImpl, and less casts.

Change-Id: I98e3818380cb58d04aa5017a3047bb156ab4c9b3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/412500
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Konstantin Shcheglov <[email protected]>

Author: scheglov

pkg/analyzer/lib/src/dart/ast/ast.dart

@@ -5686,7 +5686,7 @@ final class EnumConstantDeclarationImpl extends DeclarationImpl
   final EnumConstantArgumentsImpl? arguments;
 
   @override
-  ConstructorElement? constructorElement;
+  ConstructorElementMixin? constructorElement;
 
   /// Initializes a newly created enum constant declaration.
   ///
@@ -5704,10 +5704,10 @@ final class EnumConstantDeclarationImpl extends DeclarationImpl
 
   @experimental
   @override
-  ConstructorElement2? get constructorElement2 =>
+  ConstructorElementMixin2? get constructorElement2 =>
       constructorElement?.asElement2;
 
-  set constructorElement2(ConstructorElement2? value) {
+  set constructorElement2(ConstructorElementMixin2? value) {
     constructorElement = value?.asElement;
   }
 
@@ -10860,10 +10860,10 @@ sealed class InvocationExpressionImpl extends ExpressionImpl
   TypeArgumentListImpl? _typeArguments;
 
   @override
-  List<DartType>? typeArgumentTypes;
+  List<TypeImpl>? typeArgumentTypes;
 
   @override
-  DartType? staticInvokeType;
+  TypeImpl? staticInvokeType;
 
   /// Initializes a newly created invocation.
   InvocationExpressionImpl({

pkg/analyzer/lib/src/dart/constant/constant_verifier.dart

@@ -130,7 +130,7 @@ class ConstantVerifier extends RecursiveAstVisitor<void> {
   }
 
   @override
-  void visitConstantPattern(ConstantPattern node) {
+  void visitConstantPattern(covariant ConstantPatternImpl node) {
     var expression = node.expression.unParenthesized;
     if (expression.typeOrThrow is InvalidType) {
       return;
@@ -517,7 +517,7 @@ class ConstantVerifier extends RecursiveAstVisitor<void> {
   /// Returns `false` if we can prove that `constant == value` always returns
   /// `false`, taking into account the fact that [constantType] has primitive
   /// equality.
-  bool _canBeEqual(DartType constantType, DartType valueType) {
+  bool _canBeEqual(TypeImpl constantType, TypeImpl valueType) {
     if (constantType is InterfaceType) {
       if (valueType is InterfaceTypeImpl) {
         if (constantType.isDartCoreInt && valueType.isDartCoreDouble) {
@@ -776,7 +776,7 @@ class ConstantVerifier extends RecursiveAstVisitor<void> {
 
   /// Check if the object [obj] matches the type [type] according to runtime
   /// type checking rules.
-  bool _runtimeTypeMatch(DartObjectImpl obj, DartType type) {
+  bool _runtimeTypeMatch(DartObjectImpl obj, TypeImpl type) {
     return _currentLibrary.typeSystem.runtimeTypeMatch(obj, type);
   }
 

pkg/analyzer/lib/src/dart/constant/evaluation.dart

@@ -2910,7 +2910,8 @@ class _InstanceCreationEvaluator {
         if (baseParameter.isInitializingFormal) {
           var field = (parameter as FieldFormalParameterElement).field;
           if (field != null) {
-            var fieldType = field.type;
+            // TODO(scheglov): eliminate this cast
+            var fieldType = field.type as TypeImpl;
             if (fieldType != parameter.type) {
               // We've already checked that the argument can be assigned to the
               // parameter; we also need to check that it can be assigned to
@@ -3192,7 +3193,7 @@ extension RuntimeExtensions on TypeSystemImpl {
   /// type-checking rules.
   bool runtimeTypeMatch(
     DartObjectImpl obj,
-    DartType type,
+    TypeImpl type,
   ) {
     type = type.extensionTypeErasure;
     var objType = obj.type;

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

@@ -1807,6 +1807,9 @@ mixin ConstructorElementMixin2
   @override
   ConstructorElementImpl2 get baseElement;
 
+  @override
+  InterfaceElementImpl2 get enclosingElement2;
+
   @override
   InterfaceTypeImpl get returnType;
 }
@@ -1974,10 +1977,9 @@ class DefaultSuperFormalParameterElementImpl
       return null;
     }
 
+    // TODO(scheglov): eliminate this cast
+    superDefault as DartObjectImpl;
     var superDefaultType = superDefault.type;
-    if (superDefaultType == null) {
-      return null;
-    }
 
     var typeSystem = library?.typeSystem;
     if (typeSystem == null) {
@@ -3745,12 +3747,12 @@ class EnumElementImpl2 extends InterfaceElementImpl2
   }
 
   @override
-  List<FieldElement> get constants {
+  List<FieldElementOrMember> get constants {
     return fields.where((field) => field.isEnumConstant).toList();
   }
 
   @override
-  List<FieldElement2> get constants2 =>
+  List<FieldElement2OrMember> get constants2 =>
       constants.map((e) => e.asElement2).toList();
 
   @override
@@ -4328,7 +4330,7 @@ class ExtensionTypeElementImpl2 extends InterfaceElementImpl2
   ConstructorElement2 get primaryConstructor2 => primaryConstructor.element;
 
   @override
-  FieldElement2 get representation2 => representation.asElement2;
+  FieldElement2OrMember get representation2 => representation.asElement2;
 
   @override
   T? accept2<T>(ElementVisitor2<T> visitor) {
@@ -4489,7 +4491,7 @@ class FieldElementImpl2 extends PropertyInducingElementImpl2
   }
 
   @override
-  GetterElement? get getter2 => firstFragment.getter?.element as GetterElement?;
+  GetterElementImpl? get getter2 => firstFragment.getter?.element;
 
   @override
   bool get hasImplicitType => firstFragment.hasImplicitType;
@@ -4533,7 +4535,7 @@ class FieldElementImpl2 extends PropertyInducingElementImpl2
   String? get name3 => firstFragment.name2;
 
   @override
-  SetterElement? get setter2 => firstFragment.setter?.element as SetterElement?;
+  SetterElementImpl? get setter2 => firstFragment.setter?.element;
 
   @override
   TypeImpl get type => firstFragment.type;
@@ -4611,8 +4613,9 @@ class FieldFormalParameterElementImpl2 extends FormalParameterElementImpl
   FieldFormalParameterElementImpl2(super.firstFragment);
 
   @override
-  FieldElement2? get field2 => switch (firstFragment) {
-        FieldFormalParameterElementImpl(:FieldFragment field) => field.element,
+  FieldElementImpl2? get field2 => switch (firstFragment) {
+        FieldFormalParameterElementImpl(:FieldElementImpl field) =>
+          field.element,
         _ => null,
       };
 
@@ -5940,11 +5943,11 @@ abstract class InstanceElementImpl2 extends ElementImpl2
   InstanceElementImpl get firstFragment;
 
   @override
-  List<GetterElement> get getters2 {
+  List<GetterElement2OrMember> get getters2 {
     _readMembers();
     return accessors
         .where((e) => e.isGetter)
-        .map((e) => e.asElement2 as GetterElement?)
+        .map((e) => e.asElement2 as GetterElement2OrMember)
         .nonNulls
         .toList();
   }
@@ -6484,7 +6487,7 @@ abstract class InterfaceElementImpl extends InstanceElementImpl
   }
 
   @override
-  PropertyAccessorElement? getSetter(String setterName) {
+  PropertyAccessorElementOrMember? getSetter(String setterName) {
     return getSetterFromAccessors(setterName, accessors);
   }
 
@@ -6708,8 +6711,8 @@ abstract class InterfaceElementImpl extends InstanceElementImpl
     }
   }
 
-  static PropertyAccessorElement? getSetterFromAccessors(
-      String setterName, List<PropertyAccessorElement> accessors) {
+  static PropertyAccessorElementOrMember? getSetterFromAccessors(
+      String setterName, List<PropertyAccessorElementOrMember> accessors) {
     // Do we need the check for isSetter below?
     if (!setterName.endsWith('=')) {
       setterName += '=';
@@ -7443,12 +7446,12 @@ class LibraryElementImpl extends ElementImpl
   }
 
   @override
-  List<GetterElement> get getters {
-    var declarations = <GetterElement>{};
+  List<GetterElement2OrMember> get getters {
+    var declarations = <GetterElement2OrMember>{};
     for (var unit in units) {
       declarations.addAll(unit._accessors
           .where((accessor) => accessor.isGetter)
-          .map((accessor) => (accessor as GetterFragment).element));
+          .map((accessor) => accessor.element as GetterElement2OrMember));
     }
     return declarations.toList();
   }
@@ -10441,7 +10444,13 @@ abstract class PropertyAccessorElementOrMember
 /// Common base class for all analyzer-internal classes that implement
 /// [PropertyInducingElement2].
 abstract class PropertyInducingElement2OrMember
-    implements VariableElement2OrMember, PropertyInducingElement2 {}
+    implements VariableElement2OrMember, PropertyInducingElement2 {
+  @override
+  GetterElement2OrMember? get getter2;
+
+  @override
+  SetterElement2OrMember? get setter2;
+}
 
 /// A concrete implementation of a [PropertyInducingElement].
 abstract class PropertyInducingElementImpl
@@ -10936,7 +10945,7 @@ class SuperFormalParameterElementImpl2 extends FormalParameterElementImpl
   }
 
   @override
-  FormalParameterElement? get superConstructorParameter2 {
+  FormalParameterElementMixin? get superConstructorParameter2 {
     return firstFragment.superConstructorParameter?.asElement2;
   }
 
@@ -11097,7 +11106,8 @@ class TopLevelVariableElementImpl2 extends PropertyInducingElementImpl2
   }
 
   @override
-  GetterElement? get getter2 => firstFragment.getter2?.element;
+  GetterElementImpl? get getter2 =>
+      firstFragment.getter2?.element as GetterElementImpl?;
 
   @override
   bool get hasImplicitType => firstFragment.hasImplicitType;
@@ -11129,7 +11139,8 @@ class TopLevelVariableElementImpl2 extends PropertyInducingElementImpl2
   String? get name3 => firstFragment.name2;
 
   @override
-  SetterElement? get setter2 => firstFragment.setter2?.element;
+  SetterElementImpl? get setter2 =>
+      firstFragment.setter2?.element as SetterElementImpl?;
 
   @override
   TypeImpl get type => firstFragment.type;

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

@@ -399,7 +399,7 @@ class GenericInferrer {
   void _checkArgumentsNotMatchingBounds({
     required SyntacticEntity? errorEntity,
     required ErrorReporter? errorReporter,
-    required List<DartType> typeArguments,
+    required List<TypeImpl> typeArguments,
   }) {
     for (int i = 0; i < _typeFormals.length; i++) {
       var parameter = _typeFormals[i];

pkg/analyzer/lib/src/dart/element/inheritance_manager3.dart

@@ -83,27 +83,22 @@ class InheritanceManager3 {
   /// not `null`, add a new [Conflict] to it.
   ExecutableElementOrMember? combineSignatures({
     required InterfaceElement targetClass,
-    required List<ExecutableElement> candidates,
+    required List<ExecutableElementOrMember> candidates,
     required bool doTopMerge,
     required Name name,
     List<Conflict>? conflicts,
   }) {
     // If just one candidate, it is always valid.
     if (candidates.length == 1) {
-      // TODO(paulberry): eliminate this cast by changing the type of the
-      // parameter `candidates`.
-      return candidates[0] as ExecutableElementOrMember;
+      return candidates[0];
     }
 
     var targetLibrary = targetClass.library as LibraryElementImpl;
     var typeSystem = targetLibrary.typeSystem;
 
     var validOverrides = <ExecutableElementOrMember>[];
     for (var i = 0; i < candidates.length; i++) {
-      // TODO(paulberry): eliminate this cast by changing the type of the
-      // parameter `candidates`.
-      ExecutableElementOrMember? validOverride =
-          candidates[i] as ExecutableElementOrMember;
+      ExecutableElementOrMember? validOverride = candidates[i];
       var validOverrideType = validOverride.type;
       for (var j = 0; j < candidates.length; j++) {
         var candidate = candidates[j];
@@ -136,7 +131,7 @@ class InheritanceManager3 {
   }
 
   /// Return the result of [getInherited2] with [type] substitution.
-  ExecutableElement? getInherited(InterfaceType type, Name name) {
+  ExecutableElementOrMember? getInherited(InterfaceType type, Name name) {
     var rawElement = getInherited2(type.element, name);
     if (rawElement == null) {
       return null;
@@ -228,7 +223,7 @@ class InheritanceManager3 {
       _findMostSpecificFromNamedCandidates(
         element,
         inheritedMap,
-        element is ExtensionTypeElement
+        element is ExtensionTypeElementImpl
             ? interface.redeclared
             : interface.overridden,
         doTopMerge: false,
@@ -417,7 +412,8 @@ class InheritanceManager3 {
   /// Return all members of mixins, superclasses, and interfaces that a member
   /// with the given [name], defined in the [element], would override; or `null`
   /// if no members would be overridden.
-  List<ExecutableElementOrMember>? getOverridden2(InterfaceElement element, Name name) {
+  List<ExecutableElementOrMember>? getOverridden2(
+      InterfaceElement element, Name name) {
     var interface = getInterface(element);
     return interface.overridden[name];
   }
@@ -535,7 +531,7 @@ class InheritanceManager3 {
   List<Conflict> _findMostSpecificFromNamedCandidates(
     InterfaceElement targetClass,
     Map<Name, ExecutableElement> map,
-    Map<Name, List<ExecutableElement>> namedCandidates, {
+    Map<Name, List<ExecutableElementOrMember>> namedCandidates, {
     required bool doTopMerge,
   }) {
     var conflicts = <Conflict>[];
@@ -623,7 +619,8 @@ class InheritanceManager3 {
       //     }
       // So, each mixin always replaces members in the interface.
       // And there are individual override conflicts for each mixin.
-      var candidatesFromSuperAndMixin = <Name, List<ExecutableElement>>{};
+      var candidatesFromSuperAndMixin =
+          <Name, List<ExecutableElementOrMember>>{};
       var mixinConflicts = <Conflict>[];
       for (var entry in mixinInterface.map.entries) {
         var name = entry.key;
@@ -807,7 +804,7 @@ class InheritanceManager3 {
       }
     }
 
-    var redeclared = <Name, List<ExecutableElement>>{};
+    var redeclared = <Name, List<ExecutableElementOrMember>>{};
     var conflicts = <Conflict>[];
 
     // Add extension type members.
@@ -915,7 +912,7 @@ class InheritanceManager3 {
     }
 
     // Ensure unique overridden elements.
-    var uniqueRedeclared = <Name, List<ExecutableElement>>{};
+    var uniqueRedeclared = <Name, List<ExecutableElementOrMember>>{};
     for (var entry in redeclared.entries) {
       var name = entry.key;
       var elements = entry.value;
@@ -1267,7 +1264,7 @@ class Interface {
 
   /// The map of names to the signatures from superinterfaces that a member
   /// declaration in this extension type redeclares.
-  final Map<Name, List<ExecutableElement>> redeclared;
+  final Map<Name, List<ExecutableElementOrMember>> redeclared;
 
   /// The map of names to the signatures from superinterfaces that a member
   /// declaration in this extension type redeclares.
@@ -1308,7 +1305,7 @@ class Interface {
 
   /// The map of names to their signature in the interface.
   @experimental
-  Map<Name, ExecutableElement2> get map2 {
+  Map<Name, ExecutableElement2OrMember> get map2 {
     return map.mapValue((element) => element.asElement2);
   }
 
@@ -1420,7 +1417,7 @@ class _ExtensionTypeCandidates {
 
   _ExtensionTypeCandidates(this.name);
 
-  List<ExecutableElement> get all {
+  List<ExecutableElementOrMember> get all {
     return [...methods, ...getters, ...setters];
   }