Elements. Deprecate LocalVariableElement and subclasses.

Change-Id: Iba07661be40d1d05ddcd656413322111db3e15d4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/414822
Commit-Queue: Konstantin Shcheglov <[email protected]>
Reviewed-by: Paul Berry <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>

Author: scheglov

pkg/analyzer/api.txt

@@ -2992,7 +2992,7 @@ package:analyzer/dart/constant/value.dart:
     toSymbolValue (method: String? Function())
     toTypeValue (method: DartType? Function())
 package:analyzer/dart/element/element.dart:
-  BindPatternVariableElement (class extends Object implements PatternVariableElement):
+  BindPatternVariableElement (class extends Object implements PatternVariableElement, deprecated):
     new (constructor: BindPatternVariableElement Function())
   ClassElement (class extends Object implements InterfaceElement):
     new (constructor: ClassElement Function())
@@ -3342,7 +3342,7 @@ package:analyzer/dart/element/element.dart:
     lookUpInheritedMethod (method: MethodElement? Function(String, LibraryElement))
     lookUpMethod (method: MethodElement? Function(String, LibraryElement), deprecated)
     lookUpSetter (method: PropertyAccessorElement? Function(String, LibraryElement), deprecated)
-  JoinPatternVariableElement (class extends Object implements PatternVariableElement):
+  JoinPatternVariableElement (class extends Object implements PatternVariableElement, deprecated):
     new (constructor: JoinPatternVariableElement Function())
     isConsistent (getter: bool)
     variables (getter: List<PatternVariableElement>)
@@ -3397,7 +3397,7 @@ package:analyzer/dart/element/element.dart:
     package (getter: Version)
   LocalElement (class extends Object implements Element):
     new (constructor: LocalElement Function())
-  LocalVariableElement (class extends Object implements PromotableElement):
+  LocalVariableElement (class extends Object implements PromotableElement, deprecated):
     new (constructor: LocalVariableElement Function())
     hasInitializer (getter: bool)
     name (getter: String)
@@ -3438,7 +3438,7 @@ package:analyzer/dart/element/element.dart:
   PartElement (class extends Object implements _ExistingElement):
     new (constructor: PartElement Function())
     uri (getter: DirectiveUri)
-  PatternVariableElement (class extends Object implements LocalVariableElement):
+  PatternVariableElement (class extends Object implements LocalVariableElement, deprecated):
     new (constructor: PatternVariableElement Function())
     join (getter: JoinPatternVariableElement?)
   PrefixElement (class extends Object implements _ExistingElement):

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

@@ -62,6 +62,8 @@ import 'package:pub_semver/pub_semver.dart';
 /// A pattern variable that is explicitly declared.
 ///
 /// Clients may not extend, implement or mix-in this class.
+@Deprecated(
+    'Use BindPatternVariableFragment and BindPatternVariableElement2 instead')
 abstract class BindPatternVariableElement implements PatternVariableElement {}
 
 /// An element that represents a class or a mixin. The class can be defined by
@@ -1580,6 +1582,8 @@ abstract class InterfaceElement implements InstanceElement {
 /// for a logical-or patterns, or shared `case` bodies in `switch` statements.
 ///
 /// Clients may not extend, implement or mix-in this class.
+@Deprecated(
+    'Use JoinPatternVariableFragment and JoinPatternVariableElement2 instead')
 abstract class JoinPatternVariableElement implements PatternVariableElement {
   /// Whether the [variables] are consistent, present in all branches,
   /// and have the same type and finality.
@@ -1770,6 +1774,7 @@ abstract class LocalElement implements Element {}
 /// A local variable.
 ///
 /// Clients may not extend, implement or mix-in this class.
+@Deprecated('Use LocalVariableFragment and LocalVariableElement2 instead')
 abstract class LocalVariableElement implements PromotableElement {
   /// Whether the variable has an initializer at declaration.
   bool get hasInitializer;
@@ -1946,6 +1951,7 @@ abstract class PartElement implements _ExistingElement {
 /// A pattern variable.
 ///
 /// Clients may not extend, implement or mix-in this class.
+@Deprecated('Use PatternVariableFragment and PatternVariableElement2 instead')
 abstract class PatternVariableElement implements LocalVariableElement {
   /// The variable in which this variable joins with other pattern variables
   /// with the same name, in a logical-or pattern, or shared case scope.

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

@@ -78,7 +78,10 @@ mixin AugmentableFragment on ElementImpl {
 }
 
 class BindPatternVariableElementImpl extends PatternVariableElementImpl
-    implements BindPatternVariableElement, BindPatternVariableFragment {
+    implements
+        // ignore: deprecated_member_use_from_same_package
+        BindPatternVariableElement,
+        BindPatternVariableFragment {
   final DeclaredVariablePatternImpl node;
 
   /// This flag is set to `true` if this variable clashes with another
@@ -1357,7 +1360,7 @@ class ConstFieldElementImpl extends FieldElementImpl with ConstVariableElement {
   }
 }
 
-/// A [LocalVariableElement] for a local 'const' variable that has an
+/// A `LocalVariableElement` for a local 'const' variable that has an
 /// initializer.
 class ConstLocalVariableElementImpl extends LocalVariableElementImpl
     with ConstVariableElement {
@@ -6738,7 +6741,10 @@ abstract class InterfaceElementImpl2 extends InstanceElementImpl2
 }
 
 class JoinPatternVariableElementImpl extends PatternVariableElementImpl
-    implements JoinPatternVariableElement, JoinPatternVariableFragment {
+    implements
+        // ignore: deprecated_member_use_from_same_package
+        JoinPatternVariableElement,
+        JoinPatternVariableFragment {
   @override
   final List<PatternVariableElementImpl> variables;
 
@@ -7611,7 +7617,7 @@ class LibraryImportElementImpl extends _ExistingElementImpl
   LibraryElementImpl get library2 => super.library2 as LibraryElementImpl;
 
   @override
-  LibraryFragment get libraryFragment => enclosingElement3;
+  CompilationUnitElementImpl get libraryFragment => enclosingElement3;
 
   @override
   Namespace get namespace {
@@ -7786,9 +7792,9 @@ class LocalFunctionFragmentImpl extends FunctionElementImpl
   }
 }
 
-/// A concrete implementation of a [LocalVariableElement].
 class LocalVariableElementImpl extends NonParameterVariableElementImpl
     implements
+        // ignore: deprecated_member_use_from_same_package
         LocalVariableElement,
         LocalVariableFragment,
         VariableElementOrMember {
@@ -9677,7 +9683,10 @@ class PartElementImpl extends _ExistingElementImpl
 }
 
 class PatternVariableElementImpl extends LocalVariableElementImpl
-    implements PatternVariableElement, PatternVariableFragment {
+    implements
+        // ignore: deprecated_member_use_from_same_package
+        PatternVariableElement,
+        PatternVariableFragment {
   @override
   JoinPatternVariableElementImpl? join;
 

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

@@ -84,6 +84,13 @@ extension Element2Extension on Element2 {
   }
 }
 
+extension Element2OrNullExtension on Element2? {
+  /// Return true if this element is a wildcard variable.
+  bool get isWildcardVariable {
+    return this?.isWildcardVariable ?? false;
+  }
+}
+
 extension ElementAnnotationExtensions on ElementAnnotation {
   static final Map<String, TargetKind> _targetKindsByName = {
     for (var kind in TargetKind.values) kind.name: kind,
@@ -175,32 +182,6 @@ extension ElementExtension on Element {
     }
     return false;
   }
-
-  /// Return true if this element is a wildcard variable.
-  bool get isWildcardVariable {
-    return name == '_' &&
-        (this is LocalVariableElement ||
-            this is PrefixElement ||
-            this is TypeParameterElement ||
-            (this is ParameterElement &&
-                this is! FieldFormalParameterElement &&
-                this is! SuperFormalParameterElement)) &&
-        library.asElement2.hasWildcardVariablesFeatureEnabled;
-  }
-}
-
-extension ElementImplExtension on ElementImpl {
-  /// Return true if this element is a wildcard variable.
-  bool get isWildcardVariable {
-    return name == '_' &&
-        (this is LocalVariableElement ||
-            this is PrefixElement ||
-            this is TypeParameterElement ||
-            (this is ParameterElement &&
-                this is! FieldFormalParameterElement &&
-                this is! SuperFormalParameterElement)) &&
-        library.asElement2.hasWildcardVariablesFeatureEnabled;
-  }
 }
 
 extension ExecutableElement2OrMemberQuestionExtension

pkg/analyzer/lib/src/dart/micro/resolve_file.dart

@@ -9,7 +9,6 @@ import 'dart:typed_data';
 import 'package:analyzer/dart/analysis/declared_variables.dart';
 import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/dart/analysis/results.dart';
-import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/element2.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/file_system/file_system.dart';
@@ -259,24 +258,14 @@ class FileResolver {
   ///  cached by the resolver are searched, generated files are ignored.
   Future<List<CiderSearchMatch>> findReferences(Element2 element,
       {OperationPerformanceImpl? performance}) {
-    return findReferences2(
-      element.asElement!,
-      performance: performance,
-    );
-  }
-
-  /// Looks for references to the given Element. All the files currently
-  ///  cached by the resolver are searched, generated files are ignored.
-  Future<List<CiderSearchMatch>> findReferences2(Element element,
-      {OperationPerformanceImpl? performance}) {
-    return logger.runAsync('findReferences for ${element.name}', () async {
+    return logger.runAsync('findReferences for ${element.name3}', () async {
       var references = <CiderSearchMatch>[];
 
       Future<void> collectReferences2(
           String path, OperationPerformanceImpl performance) async {
         await performance.runAsync('collectReferences', (_) async {
           var resolved = await resolve(path: path);
-          var collector = ReferencesCollector(element);
+          var collector = ReferencesCollector(element.asElement!);
           resolved.unit.accept(collector);
           var matches = collector.references;
           if (matches.isNotEmpty) {
@@ -295,10 +284,13 @@ class FileResolver {
 
       performance ??= OperationPerformanceImpl('<default>');
       // TODO(keertip): check if element is named constructor.
-      if (element is LocalVariableElement ||
-          (element is ParameterElement && !element.isNamed)) {
-        await collectReferences2(element.source!.fullName, performance!);
-      } else if (element is LibraryImportElementImpl) {
+      if (element is LocalVariableElement2 ||
+          (element is FormalParameterElement && !element.isNamed)) {
+        await collectReferences2(
+          element.firstFragment.libraryFragment!.source.fullName,
+          performance!,
+        );
+      } else if (element is MockLibraryImportElement) {
         return await _searchReferences_Import(element);
       } else {
         var result = performance!.run('getFilesContaining', (performance) {
@@ -892,13 +884,14 @@ class FileResolver {
   }
 
   Future<List<CiderSearchMatch>> _searchReferences_Import(
-      LibraryImportElementImpl element) async {
+      MockLibraryImportElement element) async {
     var results = <CiderSearchMatch>[];
-    var libraryElement = element.library;
-    for (var unitElement in libraryElement.units) {
-      String unitPath = unitElement.source.fullName;
+    var libraryElement = element.library2;
+    for (var libraryFragment in libraryElement.fragments) {
+      String unitPath = libraryFragment.source.fullName;
       var unitResult = await resolve(path: unitPath);
-      var visitor = ImportElementReferencesVisitor(element, unitElement);
+      var visitor =
+          ImportElementReferencesVisitor(element.import, libraryFragment);
       unitResult.unit.accept(visitor);
       var lineInfo = unitResult.lineInfo;
       var infos = visitor.results

pkg/analyzer/lib/src/error/duplicate_definition_verifier.dart

@@ -214,7 +214,7 @@ class DuplicateDefinitionVerifier {
   void _checkDuplicateIdentifier(
       Map<String, Element> getterScope, Token identifier,
       {required ElementImpl element, Map<String, Element>? setterScope}) {
-    if (identifier.isSynthetic || element.isWildcardVariable) {
+    if (identifier.isSynthetic || element.asElement2.isWildcardVariable) {
       return;
     }
 
@@ -506,7 +506,7 @@ class MemberDuplicateDefinitionVerifier {
   void _checkDuplicateIdentifier(
       Map<String, Element> getterScope, Token identifier,
       {required Element element, Map<String, Element>? setterScope}) {
-    if (identifier.isSynthetic || element.isWildcardVariable) {
+    if (identifier.isSynthetic || element.asElement2.isWildcardVariable) {
       return;
     }
 

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

@@ -20,16 +20,16 @@ class MockLibraryImportElement implements Element2, PrefixFragment {
       : import = import as LibraryImportElementImpl;
 
   @override
-  Element2? get enclosingElement2 => library2;
+  LibraryElement2 get enclosingElement2 => library2;
 
   @override
   ElementKind get kind => ElementKind.IMPORT;
 
   @override
-  LibraryElement2? get library2 => libraryFragment.element;
+  LibraryElementImpl get library2 => libraryFragment.element;
 
   @override
-  LibraryFragment get libraryFragment => import.libraryFragment;
+  CompilationUnitElementImpl get libraryFragment => import.libraryFragment;
 
   @override
   String? get name3 => import.prefix2?.name2;