Elements. Use more 'asElement2' in InheritanceManager3.

Use '.asElement' to map InterfaceElement2 into 'InterfaceElement'.

Add and use `mapValue` extension method.

Change-Id: I63eb5401d33a696c688a522b463434ef5f3f8ed9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/394322
Commit-Queue: Konstantin Shcheglov <[email protected]>
Reviewed-by: Samuel Rawlins <[email protected]>

Author: scheglov

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

@@ -153,10 +153,7 @@ class InheritanceManager3 {
   @experimental
   ExecutableElement2? getInherited3(InterfaceType type, Name name) {
     var element = getInherited(type, name);
-    if (element is ExecutableMember) {
-      return element as ExecutableElement2;
-    }
-    return (element as ExecutableFragment?)?.element;
+    return element.asElement2;
   }
 
   /// Returns the most specific signature of the member with the given [name]
@@ -169,20 +166,17 @@ class InheritanceManager3 {
   // This is a replacement for `getInherited2`.
   @experimental
   ExecutableElement2? getInherited4(InterfaceElement2 element, Name name) {
-    var oldElement = getInheritedMap2(
-        (element as AugmentedInterfaceElement).firstFragment)[name];
-    return (oldElement as ExecutableFragment?)?.element;
+    var oldElement = getInheritedMap2(element.asElement)[name];
+    return oldElement.asElement2;
   }
 
   /// Returns signatures of all concrete members that the given [element]
   /// inherits from the superclasses and mixins.
   @experimental
   Map<Name, ExecutableElement2> getInheritedConcreteMap(
       InterfaceElement2 element) {
-    var map = getInheritedConcreteMap2(
-        (element as AugmentedInterfaceElement).firstFragment);
-    return map.map((name, element) =>
-        MapEntry(name, (element as ExecutableFragment).element));
+    var map = getInheritedConcreteMap2(element.asElement);
+    return map.mapValue((element) => element.asElement2);
   }
 
   /// Return signatures of all concrete members that the given [element] inherits
@@ -205,10 +199,8 @@ class InheritanceManager3 {
   /// will not be included.
   @experimental
   Map<Name, ExecutableElement2> getInheritedMap(InterfaceElement2 element) {
-    var map =
-        getInheritedMap2((element as AugmentedInterfaceElement).firstFragment);
-    return map.map((name, element) =>
-        MapEntry(name, (element as ExecutableFragment).element));
+    var map = getInheritedMap2(element.asElement);
+    return map.mapValue((element) => element.asElement2);
   }
 
   /// Return the mapping from names to most specific signatures of members
@@ -271,7 +263,7 @@ class InheritanceManager3 {
   /// all libraries.
   @experimental
   Interface getInterface2(InterfaceElement2 element) {
-    return getInterface((element as AugmentedInterfaceElement).firstFragment);
+    return getInterface(element.asElement);
   }
 
   /// Return the result of [getMember2] with [type] substitution.
@@ -378,7 +370,7 @@ class InheritanceManager3 {
     bool forSuper = false,
   }) {
     var oldElement = getMember2(
-      (element as AugmentedInterfaceElement).firstFragment,
+      element.asElement,
       name,
       concrete: concrete,
       forMixinIndex: forMixinIndex,
@@ -395,7 +387,7 @@ class InheritanceManager3 {
   List<ExecutableElement2>? getOverridden(
       InterfaceElement2 element, Name name) {
     var elements = getOverridden2(
-      (element as AugmentedInterfaceElement).firstFragment,
+      element.asElement,
       name,
     );
     if (elements == null) {
@@ -1274,14 +1266,13 @@ class Interface {
   /// The map of declared names to their signatures.
   @experimental
   Map<Name, ExecutableElement2> get declared2 {
-    return declared.map((name, element) =>
-        MapEntry(name, (element as ExecutableFragment).element));
+    return declared.mapValue((element) => element.asElement2);
   }
 
   /// The map of names to their signature in the interface.
   @experimental
   Map<Name, ExecutableElement2> get map2 {
-    return map.map((name, element) => MapEntry(name, element.asElement2));
+    return map.mapValue((element) => element.asElement2);
   }
 
   /// Return `true` if the [name] is implemented in the supertype.

pkg/analyzer/lib/src/utilities/extensions/collection.dart

@@ -107,6 +107,13 @@ extension MapExtension<K, V> on Map<K, V> {
   K? get firstKey {
     return keys.firstOrNull;
   }
+
+  Map<K, V2> mapValue<V2>(V2 Function(V) convert) {
+    return map((key, value) {
+      var value2 = convert(value);
+      return MapEntry(key, value2);
+    });
+  }
 }
 
 extension MapOfListExtension<K, V> on Map<K, List<V>> {

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

@@ -184,6 +184,12 @@ extension ExecutableElementExtension on ExecutableElement {
   }
 }
 
+extension ExecutableElementOrNullExtension on ExecutableElement? {
+  ExecutableElement2? get asElement2 {
+    return this?.asElement2;
+  }
+}
+
 extension FormalParameterExtension on FormalParameterElement {
   void appendToWithoutDelimiters(
     StringBuffer buffer, {
@@ -205,6 +211,12 @@ extension FormalParameterExtension on FormalParameterElement {
   }
 }
 
+extension InterfaceElement2Extension on InterfaceElement2 {
+  InterfaceElement get asElement {
+    return firstFragment as InterfaceElement;
+  }
+}
+
 extension InterfaceElementExtension on InterfaceElement {
   InterfaceElement2 get asElement2 {
     return (this as InterfaceElementImpl).element;

pkg/analyzer/test/src/utilities/extensions/collection_test.dart

@@ -119,6 +119,10 @@ class MapExtensionTest {
     expect({0: 1, 2: 3}.firstKey, 0);
     expect(<int, int>{}.firstKey, isNull);
   }
+
+  test_mapValue() {
+    expect({0: 1, 2: 3}.mapValue((v) => 'v$v'), {0: 'v1', 2: 'v3'});
+  }
 }
 
 @reflectiveTest