Elements. Remove 'FunctionExpressionImpl.declaredElement2'

Change-Id: Ie398dc23d6d5911dd02104ca4b31114d5d657153
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/395050
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Konstantin Shcheglov <[email protected]>

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

@@ -160,7 +160,7 @@ class AddNullCheck extends ResolvedCorrectionProducer {
       if (enclosingExecutable is MethodDeclaration) {
         toType = enclosingExecutable.returnType?.type;
       } else if (enclosingExecutable is FunctionExpressionImpl) {
-        toType = enclosingExecutable.returnType;
+        toType = enclosingExecutable.declaredFragment!.element.returnType;
       }
     } else if (parent is BinaryExpression) {
       if (typeSystem.isNonNullable(fromType)) {

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

@@ -185,7 +185,7 @@ class ConvertIntoBlockBody extends ResolvedCorrectionProducer {
     } else if (node is ConstructorDeclaration) {
       return node.declaredFragment?.element;
     } else if (node is FunctionExpression) {
-      return node.declaredFragment?.element ?? node.declaredElement2;
+      return node.declaredFragment?.element;
     }
     return null;
   }

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

@@ -8406,15 +8406,6 @@ abstract final class FunctionExpression implements Expression {
   /// hasn't been resolved.
   ExecutableElement? get declaredElement;
 
-  /// The element defined by this function expression.
-  ///
-  /// Returns `null` if the AST structure hasn't been resolved.
-  ///
-  /// Returns `null` if this expression is not a closure, and the parent is
-  /// not a local function.
-  @experimental
-  LocalFunctionElement? get declaredElement2;
-
   /// The fragment declared by this function expression.
   ///
   /// Returns `null` if the AST structure hasn't been resolved.
@@ -8451,7 +8442,7 @@ final class FunctionExpressionImpl extends ExpressionImpl
   ExecutableElementImpl? declaredElement;
 
   @override
-  LocalFunctionElementImpl? declaredElement2;
+  ExecutableElementImpl? declaredFragment;
 
   /// Initializes a newly created function declaration.
   FunctionExpressionImpl({
@@ -8483,14 +8474,6 @@ final class FunctionExpressionImpl extends ExpressionImpl
     _body = _becomeParentOf(functionBody);
   }
 
-  @override
-  ExecutableFragment? get declaredFragment {
-    if (declaredElement?.enclosingElement3 is CompilationUnitElement) {
-      return declaredElement;
-    }
-    return null;
-  }
-
   @override
   Token get endToken {
     return _body.endToken;
@@ -8506,15 +8489,6 @@ final class FunctionExpressionImpl extends ExpressionImpl
   @override
   Precedence get precedence => Precedence.primary;
 
-  DartType get returnType {
-    // If a closure, or a local function.
-    if (declaredElement2 case var declaredElement?) {
-      return declaredElement.returnType;
-    }
-    // SAFETY: must be a top-level function.
-    return declaredFragment!.element.returnType;
-  }
-
   @override
   TypeParameterListImpl? get typeParameters => _typeParameters;
 

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

@@ -698,12 +698,14 @@ class ResolutionVisitor extends RecursiveAstVisitor<void> {
           : _elementWalker!.getFunction();
       node.declaredElement = element;
       expression.declaredElement = element;
+      expression.declaredFragment = element;
     } else {
       var functionElement = node.declaredElement as FunctionElementImpl;
+      functionElement.element = LocalFunctionElementImpl(functionElement);
+
       element = functionElement;
       expression.declaredElement = functionElement;
-      expression.declaredElement2 =
-          functionElement.element as LocalFunctionElementImpl?;
+      expression.declaredFragment = functionElement;
 
       _setCodeRange(element, node);
       setElementDocumentationComment(element, node);
@@ -767,11 +769,11 @@ class ResolutionVisitor extends RecursiveAstVisitor<void> {
   @override
   void visitFunctionExpression(covariant FunctionExpressionImpl node) {
     var fragment = FunctionElementImpl.forOffset(node.offset);
+    fragment.element = LocalFunctionElementImpl(fragment);
+
     _elementHolder.enclose(fragment);
     node.declaredElement = fragment;
-
-    var element = LocalFunctionElementImpl(fragment);
-    node.declaredElement2 = element;
+    node.declaredFragment = fragment;
 
     fragment.hasImplicitReturnType = true;
     fragment.returnType = DynamicTypeImpl.instance;
@@ -1480,8 +1482,8 @@ class ResolutionVisitor extends RecursiveAstVisitor<void> {
     fragment.nameOffset2 = nameToken.offsetIfNotEmpty;
     node.declaredElement = fragment;
 
-    var element = LocalFunctionElementImpl(fragment);
-    node.functionExpression.declaredElement2 = element;
+    fragment.element = LocalFunctionElementImpl(fragment);
+    node.functionExpression.declaredFragment = fragment;
 
     // The fragment's old enclosing element needs to be set before we can get
     // the new element for it.

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

@@ -227,7 +227,7 @@ class ErrorHandlerVerifier {
       _checkErrorHandlerFunctionType(
           callback, callbackType, expectedReturnType);
       var catchErrorOnErrorExecutable = EnclosingExecutableContext.tmp(
-          callback.declaredElement2,
+          callback.declaredFragment!.element,
           isAsynchronous: true,
           catchErrorOnErrorReturnType: expectedReturnType);
       var returnStatementVerifier =

pkg/analyzer/lib/src/test_utilities/find_element2.dart

@@ -211,7 +211,7 @@ class FindElement2 extends _FindElementBase {
     unit.accept(
       FunctionAstVisitor(functionExpression: (node, local) {
         if (local) {
-          var functionElement = node.declaredElement2!;
+          var functionElement = node.declaredFragment!.element;
           findIn(functionElement.formalParameters);
         }
       }),

pkg/linter/lib/src/rules/avoid_returning_null_for_void.dart

@@ -4,7 +4,6 @@
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
-import 'package:analyzer/dart/element/element2.dart';
 import 'package:analyzer/dart/element/type.dart';
 
 import '../analyzer.dart';
@@ -59,7 +58,7 @@ class _Visitor extends SimpleAstVisitor<void> {
 
     var (type, isAsync, code) = switch (parent) {
       FunctionExpression() => (
-          parent.element?.returnType,
+          parent.declaredFragment?.element.returnType,
           parent.body.isAsynchronous,
           LinterLintCode.avoid_returning_null_for_void_from_function,
         ),
@@ -81,8 +80,3 @@ class _Visitor extends SimpleAstVisitor<void> {
     }
   }
 }
-
-extension on FunctionExpression {
-  ExecutableElement2? get element =>
-      declaredFragment?.element ?? declaredElement2;
-}

pkg/linter/lib/src/rules/unnecessary_lambdas.dart

@@ -100,7 +100,7 @@ class _Visitor extends SimpleAstVisitor<void> {
 
   @override
   void visitFunctionExpression(FunctionExpression node) {
-    var element = node.declaredElement2 ?? node.declaredFragment?.element;
+    var element = node.declaredFragment?.element;
     if (element?.name3 != '' || node.body.keyword != null) {
       return;
     }
@@ -140,8 +140,7 @@ class _Visitor extends SimpleAstVisitor<void> {
       return;
     }
 
-    var functionElement =
-        node.declaredElement2 ?? node.declaredFragment?.element;
+    var functionElement = node.declaredFragment?.element;
 
     var nodeType = functionElement?.type;
     var invocationType = expression.constructorName.element?.type;