[Elements.migrate] Migrate create_extension_member.dart

Change-Id: I2b6bc9c0c6b1e8b1e2b8345d06b207b039fd70c2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/398583
Commit-Queue: Keerti Parthasarathy <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>

Author: keertip

pkg/analysis_server/analyzer_use_new_elements.txt

@@ -32,7 +32,6 @@ lib/src/services/completion/dart/declaration_helper.dart
 lib/src/services/completion/dart/identifier_helper.dart
 lib/src/services/completion/dart/in_scope_completion_pass.dart
 lib/src/services/completion/dart/visibility_tracker.dart
-lib/src/services/correction/dart/create_extension_member.dart
 lib/src/services/correction/dart/import_library.dart
 lib/src/services/correction/dart/use_different_division_operator.dart
 lib/src/services/correction/namespace.dart

pkg/analysis_server/lib/src/services/correction/dart/create_extension_member.dart

@@ -280,9 +280,9 @@ abstract class _CreateExtensionMember extends ResolvedCorrectionProducer {
   ExtensionDeclaration? _existingExtension(DartType targetType) {
     for (var existingExtension in unitResult.unit.declarations) {
       if (existingExtension is ExtensionDeclaration) {
-        var element = existingExtension.declaredElement!;
+        var element = existingExtension.declaredFragment!.element;
         var instantiated = [element].applicableTo(
-          targetLibrary: libraryElement,
+          targetLibrary: libraryElement2,
           targetType: targetType,
           strictCasts: true,
         );

pkg/analyzer/lib/src/dart/resolver/applicable_extensions.dart

@@ -97,6 +97,18 @@ class InstantiatedExtensionWithoutMember {
   );
 }
 
+class InstantiatedExtensionWithoutMember2 {
+  final ExtensionElement2 extension;
+  final MapSubstitution substitution;
+  final DartType extendedType;
+
+  InstantiatedExtensionWithoutMember2(
+    this.extension,
+    this.substitution,
+    this.extendedType,
+  );
+}
+
 abstract class _NotInstantiatedExtension<R> {
   final ExtensionElement extension;
 
@@ -170,6 +182,21 @@ class _NotInstantiatedExtensionWithoutMember
   }
 }
 
+/// [_NotInstantiatedExtension2] for any [ExtensionElement2].
+class _NotInstantiatedExtensionWithoutMember2
+    extends _NotInstantiatedExtension2<InstantiatedExtensionWithoutMember2> {
+  _NotInstantiatedExtensionWithoutMember2(super.extension);
+
+  @override
+  InstantiatedExtensionWithoutMember2 instantiate({
+    required MapSubstitution substitution,
+    required DartType extendedType,
+  }) {
+    return InstantiatedExtensionWithoutMember2(
+        extension, substitution, extendedType);
+  }
+}
+
 extension ExtensionsExtensions on Iterable<ExtensionElement> {
   /// Extensions that can be applied, within [targetLibrary], to [targetType].
   List<InstantiatedExtensionWithoutMember> applicableTo({
@@ -246,6 +273,16 @@ extension ExtensionsExtensions on Iterable<ExtensionElement> {
 }
 
 extension ExtensionsExtensions2 on Iterable<ExtensionElement2> {
+  /// Extensions that can be applied, within [targetLibrary], to [targetType].
+  List<InstantiatedExtensionWithoutMember2> applicableTo({
+    required LibraryElement2 targetLibrary,
+    required DartType targetType,
+    required bool strictCasts,
+  }) {
+    return map((e) => _NotInstantiatedExtensionWithoutMember2(e))
+        .applicableTo(targetLibrary: targetLibrary, targetType: targetType);
+  }
+
   /// Returns the sublist of [ExtensionElement2]s that have an instance member
   /// named [baseName].
   List<_NotInstantiatedExtensionWithMember2> havingMemberWithBaseName(
@@ -390,3 +427,81 @@ extension NotInstantiatedExtensionsExtensions<R>
     return instantiated;
   }
 }
+
+extension NotInstantiatedExtensionsExtensions2<R>
+    on Iterable<_NotInstantiatedExtension2<R>> {
+  /// Extensions that can be applied, within [targetLibrary], to [targetType].
+  List<R> applicableTo({
+    required LibraryElement2 targetLibrary,
+    required DartType targetType,
+  }) {
+    if (identical(targetType, NeverTypeImpl.instance)) {
+      return <R>[];
+    }
+
+    targetLibrary as LibraryElementImpl;
+    var typeSystem = targetLibrary.typeSystem;
+    var genericMetadataIsEnabled = targetLibrary.featureSet.isEnabled(
+      Feature.generic_metadata,
+    );
+    var inferenceUsingBoundsIsEnabled = targetLibrary.featureSet.isEnabled(
+      Feature.inference_using_bounds,
+    );
+
+    var instantiated = <R>[];
+
+    for (var notInstantiated in this) {
+      var extension = notInstantiated.extension.asElement as ExtensionElement;
+
+      var freshTypes = getFreshTypeParameters(extension.typeParameters);
+      var freshTypeParameters = freshTypes.freshTypeParameters;
+      var rawExtendedType = freshTypes.substitute(extension.extendedType);
+      // Casts aren't relevant in extension applicability.
+      var typeSystemOperations =
+          TypeSystemOperations(typeSystem, strictCasts: false);
+
+      inferenceLogWriter?.enterGenericInference(
+          freshTypeParameters, rawExtendedType);
+      var inferrer = GenericInferrer(
+        typeSystem,
+        freshTypeParameters,
+        genericMetadataIsEnabled: genericMetadataIsEnabled,
+        inferenceUsingBoundsIsEnabled: inferenceUsingBoundsIsEnabled,
+        strictInference: false,
+        typeSystemOperations: typeSystemOperations,
+        dataForTesting: null,
+      );
+      inferrer.constrainArgument(
+        targetType,
+        rawExtendedType,
+        'extendedType',
+        nodeForTesting: null,
+      );
+      var inferredTypes = inferrer.tryChooseFinalTypes();
+      if (inferredTypes == null) {
+        continue;
+      }
+
+      var substitution = Substitution.fromPairs(
+        extension.typeParameters,
+        inferredTypes,
+      );
+      var extendedType = substitution.substituteType(
+        extension.extendedType,
+      );
+
+      if (!typeSystem.isSubtypeOf(targetType, extendedType)) {
+        continue;
+      }
+
+      instantiated.add(
+        notInstantiated.instantiate(
+          substitution: substitution,
+          extendedType: extendedType,
+        ),
+      );
+    }
+
+    return instantiated;
+  }
+}