DAS: Rename coveredNode to coveringNode; small changes

This is preparing _AbstractCorrectionProducer to be a sealed public
class for plugins:

* Move `_coveringNode` and `coveringNode` to
  CorrectionProducer from _AbstractCorrectionProducer; these are only
  used by CorrectionProducer subclasses.
* Seal CorrectionProducer; the ultimate subclasses should subclass
  either ParsedCorrectionProducer or ResolvedCorrectionProducer.
* Make CorrectionProducerContext final.

Change-Id: Iccbe0d92042eb826c6c53499e052c37442e312ba
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/367761
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Samuel Rawlins <srawlins@google.com>
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/abstract_producer.dart b/pkg/analysis_server/lib/src/services/correction/dart/abstract_producer.dart
index 19a9ff2..56a3057 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/abstract_producer.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/abstract_producer.dart
@@ -94,8 +94,15 @@
 }
 
 /// An object that can compute a correction (fix or assist) in a Dart file.
-abstract class CorrectionProducer<T extends ParsedUnitResult>
+sealed class CorrectionProducer<T extends ParsedUnitResult>
     extends _AbstractCorrectionProducer<T> {
+  /// The most deeply nested node that completely covers the highlight region of
+  /// the diagnostic, or `null` if there is no diagnostic, such a node does not
+  /// exist, or if it hasn't been computed yet.
+  ///
+  /// Use [coveringNode] to access this field.
+  AstNode? _coveringNode;
+
   /// The applicability of this producer.
   ///
   /// This property is to be implemented by each subclass, but outside code must
@@ -137,6 +144,24 @@
       applicability == CorrectionApplicability.automatically ||
       applicability == CorrectionApplicability.automaticallyButOncePerFile;
 
+  /// The most deeply nested node that completely covers the highlight region of
+  /// the diagnostic, or `null` if there is no diagnostic or if such a node does
+  /// not exist.
+  AstNode? get coveringNode {
+    if (_coveringNode == null) {
+      var diagnostic = this.diagnostic;
+      if (diagnostic == null) {
+        return null;
+      }
+      var errorOffset = diagnostic.problemMessage.offset;
+      var errorLength = diagnostic.problemMessage.length;
+      _coveringNode =
+          NodeLocator2(errorOffset, math.max(errorOffset + errorLength - 1, 0))
+              .searchWithin(unit);
+    }
+    return _coveringNode;
+  }
+
   /// The length of the source range associated with the error message being
   /// fixed, or `null` if there is no diagnostic.
   int? get errorLength => diagnostic?.problemMessage.length;
@@ -180,7 +205,7 @@
   void configure(CorrectionProducerContext<T> context);
 }
 
-class CorrectionProducerContext<UnitResult extends ParsedUnitResult> {
+final class CorrectionProducerContext<UnitResult extends ParsedUnitResult> {
   final int _selectionOffset;
   final int _selectionLength;
 
@@ -315,13 +340,13 @@
   Future<List<ResolvedCorrectionProducer>> get producers;
 }
 
-/// An object that can compute a correction (fix or assist) in a Dart file using
-/// the parsed AST.
+/// A [CorrectionProducer] that can compute a correction (fix or assist) in a
+/// Dart file using the parsed AST.
 abstract class ParsedCorrectionProducer
     extends CorrectionProducer<ParsedUnitResult> {}
 
-/// An object that can compute a correction (fix or assist) in a Dart file using
-/// the resolved AST.
+/// A [CorrectionProducer] that can compute a correction (fix or assist) in a
+/// Dart file using the resolved AST.
 abstract class ResolvedCorrectionProducer
     extends CorrectionProducer<ResolvedUnitResult> {
   AnalysisOptionsImpl get analysisOptions =>
@@ -538,42 +563,16 @@
   }
 }
 
-/// The behavior shared by [ResolvedCorrectionProducer] and
+/// The behavior shared by [CorrectionProducer] and
 /// [MultiCorrectionProducer].
-abstract class _AbstractCorrectionProducer<T extends ParsedUnitResult> {
+sealed class _AbstractCorrectionProducer<T extends ParsedUnitResult> {
   /// The context used to produce corrections.
   // TODO(migration): Make it not `late`, require in constructor.
   late CorrectionProducerContext<T> _context;
 
-  /// The most deeply nested node that completely covers the highlight region of
-  /// the diagnostic, or `null` if there is no diagnostic, such a node does not
-  /// exist, or if it hasn't been computed yet.
-  ///
-  /// Use [coveredNode] to access this field.
-  AstNode? _coveredNode;
-
   /// Whether the fixes are being built for the bulk-fix request.
   bool get applyingBulkFixes => _context._applyingBulkFixes;
 
-  /// The most deeply nested node that completely covers the highlight region of
-  /// the diagnostic, or `null` if there is no diagnostic or if such a node does
-  /// not exist.
-  AstNode? get coveredNode {
-    // TODO(brianwilkerson): Consider renaming this to `coveringNode`.
-    if (_coveredNode == null) {
-      var diagnostic = this.diagnostic;
-      if (diagnostic == null) {
-        return null;
-      }
-      var errorOffset = diagnostic.problemMessage.offset;
-      var errorLength = diagnostic.problemMessage.length;
-      _coveredNode =
-          NodeLocator2(errorOffset, math.max(errorOffset + errorLength - 1, 0))
-              .searchWithin(unit);
-    }
-    return _coveredNode;
-  }
-
   /// The diagnostic being fixed, or `null` if this producer is being
   /// used to produce an assist.
   Diagnostic? get diagnostic => _context._diagnostic;
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/add_explicit_cast.dart b/pkg/analysis_server/lib/src/services/correction/dart/add_explicit_cast.dart
index 9403871..cf989b9 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/add_explicit_cast.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/add_explicit_cast.dart
@@ -27,7 +27,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var target = coveredNode;
+    var target = coveringNode;
     if (target is! Expression) {
       return;
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/add_leading_newline_to_string.dart b/pkg/analysis_server/lib/src/services/correction/dart/add_leading_newline_to_string.dart
index 904cbed..b91febd 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/add_leading_newline_to_string.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/add_leading_newline_to_string.dart
@@ -21,7 +21,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var stringLiteral = coveredNode;
+    var stringLiteral = coveringNode;
     if (stringLiteral is! SimpleStringLiteral) {
       return;
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/add_null_check.dart b/pkg/analysis_server/lib/src/services/correction/dart/add_null_check.dart
index 7f8d3d5..62ed646 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/add_null_check.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/add_null_check.dart
@@ -43,59 +43,59 @@
   @override
   Future<void> compute(ChangeBuilder builder) async {
     Expression? target;
-    var coveredNode = this.coveredNode;
-    var coveredNodeParent = coveredNode?.parent;
+    var coveringNode = this.coveringNode;
+    var coveringNodeParent = coveringNode?.parent;
 
-    if (await _isNullAware(builder, coveredNode)) {
+    if (await _isNullAware(builder, coveringNode)) {
       return;
     }
 
-    if (coveredNode is SimpleIdentifier) {
-      if (coveredNodeParent is MethodInvocation) {
-        target = coveredNodeParent.realTarget;
-      } else if (coveredNodeParent is PrefixedIdentifier) {
-        target = coveredNodeParent.prefix;
-      } else if (coveredNodeParent is PropertyAccess) {
-        target = coveredNodeParent.realTarget;
-      } else if (coveredNodeParent is CascadeExpression &&
+    if (coveringNode is SimpleIdentifier) {
+      if (coveringNodeParent is MethodInvocation) {
+        target = coveringNodeParent.realTarget;
+      } else if (coveringNodeParent is PrefixedIdentifier) {
+        target = coveringNodeParent.prefix;
+      } else if (coveringNodeParent is PropertyAccess) {
+        target = coveringNodeParent.realTarget;
+      } else if (coveringNodeParent is CascadeExpression &&
           await _isNullAware(
-              builder, coveredNodeParent.cascadeSections.first)) {
+              builder, coveringNodeParent.cascadeSections.first)) {
         return;
       } else {
-        target = coveredNode;
+        target = coveringNode;
       }
-    } else if (coveredNode is IndexExpression) {
-      target = coveredNode.realTarget;
+    } else if (coveringNode is IndexExpression) {
+      target = coveringNode.realTarget;
       if (target.staticType?.nullabilitySuffix != NullabilitySuffix.question) {
-        target = coveredNode;
+        target = coveringNode;
       }
-    } else if (coveredNode is Expression &&
-        coveredNodeParent is FunctionExpressionInvocation) {
-      target = coveredNode;
-    } else if (coveredNodeParent is AssignmentExpression) {
-      target = coveredNodeParent.rightHandSide;
-    } else if (coveredNode is PostfixExpression) {
-      target = coveredNode.operand;
-    } else if (coveredNode is PrefixExpression) {
-      target = coveredNode.operand;
-    } else if (coveredNode is BinaryExpression) {
-      if (coveredNode.operator.type != TokenType.QUESTION_QUESTION) {
-        target = coveredNode.leftOperand;
+    } else if (coveringNode is Expression &&
+        coveringNodeParent is FunctionExpressionInvocation) {
+      target = coveringNode;
+    } else if (coveringNodeParent is AssignmentExpression) {
+      target = coveringNodeParent.rightHandSide;
+    } else if (coveringNode is PostfixExpression) {
+      target = coveringNode.operand;
+    } else if (coveringNode is PrefixExpression) {
+      target = coveringNode.operand;
+    } else if (coveringNode is BinaryExpression) {
+      if (coveringNode.operator.type != TokenType.QUESTION_QUESTION) {
+        target = coveringNode.leftOperand;
       } else {
-        var expectedType = coveredNode.staticParameterElement?.type;
+        var expectedType = coveringNode.staticParameterElement?.type;
         if (expectedType == null) return;
 
-        var leftType = coveredNode.leftOperand.staticType;
+        var leftType = coveringNode.leftOperand.staticType;
         var leftAssignable = leftType != null &&
             typeSystem.isAssignableTo(
                 typeSystem.promoteToNonNull(leftType), expectedType,
                 strictCasts: analysisOptions.strictCasts);
         if (leftAssignable) {
-          target = coveredNode.rightOperand;
+          target = coveringNode.rightOperand;
         }
       }
-    } else if (coveredNode is AsExpression) {
-      target = coveredNode.expression;
+    } else if (coveringNode is AsExpression) {
+      target = coveringNode.expression;
     }
 
     if (target == null) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/change_type_annotation.dart b/pkg/analysis_server/lib/src/services/correction/dart/change_type_annotation.dart
index a256c59..cf79ddf 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/change_type_annotation.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/change_type_annotation.dart
@@ -29,13 +29,13 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var declaration = coveredNode?.parent;
+    var declaration = coveringNode?.parent;
     if (declaration is! VariableDeclaration) {
       return;
     }
 
     var initializer = declaration.initializer;
-    if (initializer == null || initializer != coveredNode) {
+    if (initializer == null || initializer != coveringNode) {
       return;
     }
 
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/convert_to_null_aware_spread.dart b/pkg/analysis_server/lib/src/services/correction/dart/convert_to_null_aware_spread.dart
index 714c7de..2bd2ce9 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/convert_to_null_aware_spread.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/convert_to_null_aware_spread.dart
@@ -19,7 +19,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var parent = coveredNode?.parent;
+    var parent = coveringNode?.parent;
     if (parent is SpreadElement && !parent.isNullAware) {
       await builder.addDartFileEdit(file, (builder) {
         builder.addSimpleInsertion(parent.spreadOperator.end, '?');
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/move_type_arguments_to_class.dart b/pkg/analysis_server/lib/src/services/correction/dart/move_type_arguments_to_class.dart
index da3a044..3672183 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/move_type_arguments_to_class.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/move_type_arguments_to_class.dart
@@ -22,7 +22,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var typeArguments = coveredNode;
+    var typeArguments = coveringNode;
     if (typeArguments is! TypeArgumentList) {
       return;
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_annotation.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_annotation.dart
index 37ab901..6214ab9 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_annotation.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_annotation.dart
@@ -44,7 +44,7 @@
       );
     }
 
-    var node = coveredNode;
+    var node = coveringNode;
     if (node is Annotation) {
       await addFix(node);
     } else if (node is DefaultFormalParameter) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_dead_code.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_dead_code.dart
index 5515bf2..71bd83e 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_dead_code.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_dead_code.dart
@@ -20,8 +20,8 @@
       CorrectionApplicability.singleLocation;
 
   @override
-  AstNode? get coveredNode {
-    var node = super.coveredNode;
+  AstNode? get coveringNode {
+    var node = super.coveringNode;
     if (node is BinaryExpression) {
       var problemMessage = diagnostic?.problemMessage;
       if (problemMessage != null) {
@@ -41,14 +41,14 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var coveredNode = this.coveredNode;
-    var parent = coveredNode?.parent;
+    var coveringNode = this.coveringNode;
+    var parent = coveringNode?.parent;
 
-    if (coveredNode is Expression) {
+    if (coveringNode is Expression) {
       if (parent is BinaryExpression) {
-        if (parent.rightOperand == coveredNode) {
+        if (parent.rightOperand == coveringNode) {
           await builder.addDartFileEdit(file, (builder) {
-            builder.addDeletion(range.endEnd(parent.leftOperand, coveredNode));
+            builder.addDeletion(range.endEnd(parent.leftOperand, coveringNode));
           });
         }
       } else if (parent is ForParts) {
@@ -56,8 +56,7 @@
         if (forStatement is! ForStatement) return;
         await _computeForStatementParts(builder, forStatement, parent);
       }
-    } else if (coveredNode is Block) {
-      var block = coveredNode;
+    } else if (coveringNode is Block) {
       var statementsToRemove = <Statement>[];
       var problemMessage = diagnostic?.problemMessage;
       if (problemMessage == null) {
@@ -65,7 +64,7 @@
       }
       var errorRange =
           SourceRange(problemMessage.offset, problemMessage.length);
-      for (var statement in block.statements) {
+      for (var statement in coveringNode.statements) {
         if (range.node(statement).intersects(errorRange)) {
           statementsToRemove.add(statement);
         }
@@ -76,34 +75,34 @@
           builder.addDeletion(rangeToRemove);
         });
       }
-    } else if (coveredNode is Statement) {
-      if (coveredNode is EmptyStatement) {
+    } else if (coveringNode is Statement) {
+      if (coveringNode is EmptyStatement) {
         return;
       }
-      if (coveredNode is DoStatement &&
-          await _computeDoStatement(builder, coveredNode)) {
+      if (coveringNode is DoStatement &&
+          await _computeDoStatement(builder, coveringNode)) {
         return;
       }
 
-      var rangeToRemove = utils.getLinesRangeStatements([coveredNode]);
+      var rangeToRemove = utils.getLinesRangeStatements([coveringNode]);
       await builder.addDartFileEdit(file, (builder) {
         builder.addDeletion(rangeToRemove);
       });
-    } else if (coveredNode is CatchClause && parent is TryStatement) {
+    } else if (coveringNode is CatchClause && parent is TryStatement) {
       var catchClauses = parent.catchClauses;
-      var index = catchClauses.indexOf(coveredNode);
+      var index = catchClauses.indexOf(coveringNode);
       var previous = index == 0 ? parent.body : catchClauses[index - 1];
       await builder.addDartFileEdit(file, (builder) {
-        builder.addDeletion(range.endEnd(previous, coveredNode));
+        builder.addDeletion(range.endEnd(previous, coveringNode));
       });
-    } else if (coveredNode is ForParts) {
-      var forStatement = coveredNode.parent;
+    } else if (coveringNode is ForParts) {
+      var forStatement = coveringNode.parent;
       if (forStatement is! ForStatement) return;
 
-      await _computeForStatementParts(builder, forStatement, coveredNode);
-    } else if (coveredNode is SwitchPatternCase) {
+      await _computeForStatementParts(builder, forStatement, coveringNode);
+    } else if (coveringNode is SwitchPatternCase) {
       await builder.addDartFileEdit(file, (builder) {
-        builder.addDeletion(range.deletionRange(coveredNode));
+        builder.addDeletion(range.deletionRange(coveringNode));
       });
     }
   }
@@ -171,7 +170,7 @@
 
   Future<void> _computeForStatementParts(ChangeBuilder builder,
       ForStatement forStatement, ForParts forParts) async {
-    var beginNode = coveredNode;
+    var beginNode = coveringNode;
     if (beginNode == null) return;
     var updaters = forParts.updaters;
     if (!updaters.contains(beginNode)) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_duplicate_case.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_duplicate_case.dart
index 63a0e4f..8c3e914 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_duplicate_case.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_duplicate_case.dart
@@ -23,7 +23,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var node = coveredNode?.parent;
+    var node = coveringNode?.parent;
     if (node is! SwitchCase) {
       return;
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_name_from_combinator.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_name_from_combinator.dart
index 7aecd8d..ac5e75b 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_name_from_combinator.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_name_from_combinator.dart
@@ -26,7 +26,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var node = coveredNode;
+    var node = coveringNode;
     if (node is SimpleIdentifier) {
       var parent = node.parent;
       if (parent is Combinator) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_parentheses_in_getter_invocation.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_parentheses_in_getter_invocation.dart
index fa50921..00f9365 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_parentheses_in_getter_invocation.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_parentheses_in_getter_invocation.dart
@@ -20,7 +20,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var invocation = coveredNode?.parent;
+    var invocation = coveringNode?.parent;
     if (invocation is FunctionExpressionInvocation) {
       await builder.addDartFileEdit(file, (builder) {
         builder.addDeletion(range.node(invocation.argumentList));
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_type_arguments.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_type_arguments.dart
index 50ca2a9..c84f914 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_type_arguments.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_type_arguments.dart
@@ -20,7 +20,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var typeArguments = coveredNode;
+    var typeArguments = coveringNode;
     if (typeArguments is! TypeArgumentList) {
       return;
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_unnecessary_cast.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_unnecessary_cast.dart
index 052dbcf..76eeff4 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_unnecessary_cast.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_unnecessary_cast.dart
@@ -24,7 +24,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var asExpression = coveredNode;
+    var asExpression = coveringNode;
     if (asExpression is! AsExpression) {
       return;
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_unnecessary_parentheses.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_unnecessary_parentheses.dart
index 3cc7a20..c1f9061 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_unnecessary_parentheses.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_unnecessary_parentheses.dart
@@ -22,7 +22,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var outer = coveredNode;
+    var outer = coveringNode;
     if (outer is ParenthesizedExpression &&
         outer.parent is! ParenthesizedExpression) {
       var left = outer.leftParenthesis;
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_var_keyword.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_var_keyword.dart
index 18101d6..e7d2fd3 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_var_keyword.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_var_keyword.dart
@@ -20,7 +20,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var node = coveredNode;
+    var node = coveringNode;
     if (node is DeclaredVariablePattern) {
       var keyword = node.keyword;
       if (keyword != null) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/replace_null_with_closure.dart b/pkg/analysis_server/lib/src/services/correction/dart/replace_null_with_closure.dart
index f0f3d79..9fa1527 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/replace_null_with_closure.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/replace_null_with_closure.dart
@@ -27,11 +27,11 @@
     AstNode? nodeToFix;
     var parameters = const <ParameterElement>[];
 
-    var coveredNode = this.coveredNode;
-    if (coveredNode is NamedExpression) {
-      var expression = coveredNode.expression;
+    var coveringNode = this.coveringNode;
+    if (coveringNode is NamedExpression) {
+      var expression = coveringNode.expression;
       if (expression is NullLiteral) {
-        var element = coveredNode.element;
+        var element = coveringNode.element;
         if (element is ParameterElement) {
           var type = element.type;
           if (type is FunctionType) {
@@ -40,8 +40,8 @@
         }
         nodeToFix = expression;
       }
-    } else if (coveredNode is NullLiteral) {
-      nodeToFix = coveredNode;
+    } else if (coveringNode is NullLiteral) {
+      nodeToFix = coveringNode;
     }
 
     if (nodeToFix == null) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/replace_with_not_null_aware.dart b/pkg/analysis_server/lib/src/services/correction/dart/replace_with_not_null_aware.dart
index ff35ae3..62f949d 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/replace_with_not_null_aware.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/replace_with_not_null_aware.dart
@@ -29,7 +29,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var node = coveredNode;
+    var node = coveringNode;
     if (node is MethodInvocation) {
       var operator = node.operator;
       if (operator != null) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/replace_with_null_aware.dart b/pkg/analysis_server/lib/src/services/correction/dart/replace_with_null_aware.dart
index bf8db1d..a93b883 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/replace_with_null_aware.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/replace_with_null_aware.dart
@@ -43,7 +43,7 @@
   }
 
   Future<void> _computeInChain(ChangeBuilder builder) async {
-    var node = coveredNode;
+    var node = coveringNode;
     if (node is Expression) {
       var node_final = node;
       await builder.addDartFileEdit(file, (builder) {
@@ -67,13 +67,13 @@
   }
 
   Future<void> _computeSingle(ChangeBuilder builder) async {
-    var node = coveredNode?.parent;
+    var node = coveringNode?.parent;
     if (node is CascadeExpression) {
       node = node.cascadeSections.first;
     } else {
-      var coveredNode = this.coveredNode;
-      if (coveredNode is IndexExpression) {
-        await _insert(builder, coveredNode.leftBracket);
+      var coveringNode = this.coveringNode;
+      if (coveringNode is IndexExpression) {
+        await _insert(builder, coveringNode.leftBracket);
         return;
       }
       var parent = node?.parent;
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/sort_constructor_first.dart b/pkg/analysis_server/lib/src/services/correction/dart/sort_constructor_first.dart
index 7fda7d8..86c258a 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/sort_constructor_first.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/sort_constructor_first.dart
@@ -23,7 +23,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var constructor = coveredNode?.parent;
+    var constructor = coveringNode?.parent;
     var clazz = constructor?.parent;
     if (clazz is! ClassDeclaration || constructor is! ConstructorDeclaration) {
       return;
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/sort_unnamed_constructor_first.dart b/pkg/analysis_server/lib/src/services/correction/dart/sort_unnamed_constructor_first.dart
index abc2037..2f46cbf 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/sort_unnamed_constructor_first.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/sort_unnamed_constructor_first.dart
@@ -23,7 +23,7 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var clazz = coveredNode?.parent?.parent;
+    var clazz = coveringNode?.parent?.parent;
     if (clazz is! ClassDeclaration) {
       return;
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/use_eq_eq_null.dart b/pkg/analysis_server/lib/src/services/correction/dart/use_eq_eq_null.dart
index adcb499ea..23ecdb6 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/use_eq_eq_null.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/use_eq_eq_null.dart
@@ -22,8 +22,8 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    if (coveredNode is IsExpression) {
-      var isExpression = coveredNode as IsExpression;
+    if (coveringNode is IsExpression) {
+      var isExpression = coveringNode as IsExpression;
       await builder.addDartFileEdit(file, (builder) {
         builder.addReplacement(
             range.endEnd(isExpression.expression, isExpression), (builder) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/use_not_eq_null.dart b/pkg/analysis_server/lib/src/services/correction/dart/use_not_eq_null.dart
index aea266a..cd8e844 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/use_not_eq_null.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/use_not_eq_null.dart
@@ -22,8 +22,8 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    if (coveredNode is IsExpression) {
-      var isExpression = coveredNode as IsExpression;
+    if (coveringNode is IsExpression) {
+      var isExpression = coveringNode as IsExpression;
       await builder.addDartFileEdit(file, (builder) {
         builder.addReplacement(
             range.endEnd(isExpression.expression, isExpression), (builder) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/use_rethrow.dart b/pkg/analysis_server/lib/src/services/correction/dart/use_rethrow.dart
index f1ff7e3..33952e7 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/use_rethrow.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/use_rethrow.dart
@@ -22,10 +22,10 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var coveredNode = this.coveredNode;
-    if (coveredNode is ThrowExpression) {
+    var coveringNode = this.coveringNode;
+    if (coveringNode is ThrowExpression) {
       await builder.addDartFileEdit(file, (builder) {
-        builder.addSimpleReplacement(range.node(coveredNode), 'rethrow');
+        builder.addSimpleReplacement(range.node(coveringNode), 'rethrow');
       });
     }
   }