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 8bdbc27..595f694 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
@@ -25,9 +25,7 @@
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer_plugin/utilities/assist/assist.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
-import 'package:analyzer_plugin/utilities/change_builder/change_builder_dart.dart';
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
-import 'package:analyzer_plugin/utilities/range_factory.dart';
 import 'package:meta/meta.dart';
 
 /// How broadly a [CorrectionProducer] can be applied.
@@ -117,17 +115,12 @@
   bool get canBeAppliedAutomatically =>
       applicability == CorrectionApplicability.automatically;
 
-  /// The length of the error message being fixed, or `null` if there is no
-  /// diagnostic.
+  /// 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;
 
-  /// The text of the error message being fixed, or `null` if there is no
-  /// diagnostic.
-  String? get errorMessage =>
-      diagnostic?.problemMessage.messageText(includeUrl: true);
-
-  /// The offset of the error message being fixed, or `null` if there is no
-  /// diagnostic.
+  /// The offset of the source range associated with the error message being
+  /// fixed, or `null` if there is no diagnostic.
   int? get errorOffset => diagnostic?.problemMessage.offset;
 
   /// The arguments that should be used when composing the message for a fix, or
@@ -162,9 +155,7 @@
   ///
   /// If the fix needs to dynamically set [fixKind], it should be done here.
   @override
-  void configure(CorrectionProducerContext<T> context) {
-    super.configure(context);
-  }
+  void configure(CorrectionProducerContext<T> context);
 }
 
 class CorrectionProducerContext<UnitResult extends ParsedUnitResult> {
@@ -176,11 +167,10 @@
   final AnalysisSessionHelper _sessionHelper;
   final UnitResult _unitResult;
 
-  // TODO(migration): Make it non-nullable, specialize "fix" context?
   final DartFixContext? dartFixContext;
 
-  /// A flag indicating whether the correction producers will be run in the
-  /// context of applying bulk fixes.
+  /// Whether the correction producers are run in the context of applying bulk
+  /// fixes.
   final bool _applyingBulkFixes;
 
   final Diagnostic? _diagnostic;
@@ -191,13 +181,13 @@
 
   CorrectionProducerContext._({
     required UnitResult unitResult,
-    bool applyingBulkFixes = false,
-    this.dartFixContext,
-    Diagnostic? diagnostic,
+    required bool applyingBulkFixes,
+    required this.dartFixContext,
+    required Diagnostic? diagnostic,
     required AstNode node,
     required Token token,
-    int selectionOffset = -1,
-    int selectionLength = 0,
+    required int selectionOffset,
+    required int selectionLength,
   })  : _unitResult = unitResult,
         _sessionHelper = AnalysisSessionHelper(unitResult.session),
         _utils = CorrectionUtils(unitResult),
@@ -301,12 +291,6 @@
 
   /// The individual producers generated by this producer.
   Future<List<ResolvedCorrectionProducer>> get producers;
-
-  TypeProvider get typeProvider => unitResult.typeProvider;
-
-  /// The type system appropriate to the library in which the correction is
-  /// requested.
-  TypeSystem get typeSystem => unitResult.typeSystem;
 }
 
 /// An object that can compute a correction (fix or assist) in a Dart file using
@@ -322,9 +306,6 @@
       sessionHelper.session.analysisContext
           .getAnalysisOptionsForFile(unitResult.file) as AnalysisOptionsImpl;
 
-  /// The type for the class `bool` from `dart:core`.
-  DartType get coreTypeBool => unitResult.typeProvider.boolType;
-
   /// Whether [node] is in a static context.
   bool get inStaticContext {
     // Constructor initializers cannot reference `this`.
@@ -351,6 +332,9 @@
   /// requested.
   TypeSystem get typeSystem => unitResult.typeSystem;
 
+  /// The type for the class `bool` from `dart:core`.
+  DartType get _coreTypeBool => typeProvider.boolType;
+
   /// Returns the class declaration for the given [element], or `null` if there
   /// is no such class.
   Future<ClassDeclaration?> getClassDeclaration(ClassElement element) async {
@@ -486,35 +470,35 @@
       if (parent is AssertStatement) {
         var statement = parent;
         if (statement.condition == expression) {
-          return coreTypeBool;
+          return _coreTypeBool;
         }
       }
       // `if ( myFunction() ) {}`.
       if (parent is IfStatement) {
         var statement = parent;
         if (statement.expression == expression) {
-          return coreTypeBool;
+          return _coreTypeBool;
         }
       }
       // `while ( myFunction() ) {}`.
       if (parent is WhileStatement) {
         var statement = parent;
         if (statement.condition == expression) {
-          return coreTypeBool;
+          return _coreTypeBool;
         }
       }
       // `do {} while ( myFunction() );`.
       if (parent is DoStatement) {
         var statement = parent;
         if (statement.condition == expression) {
-          return coreTypeBool;
+          return _coreTypeBool;
         }
       }
       // `!myFunction()`.
       if (parent is PrefixExpression) {
         var prefixExpression = parent;
         if (prefixExpression.operator.type == TokenType.BANG) {
-          return coreTypeBool;
+          return _coreTypeBool;
         }
       }
       // Binary expression `&&` or `||`.
@@ -523,7 +507,7 @@
         var operatorType = binaryExpression.operator.type;
         if (operatorType == TokenType.AMPERSAND_AMPERSAND ||
             operatorType == TokenType.BAR_BAR) {
-          return coreTypeBool;
+          return _coreTypeBool;
         }
       }
     }
@@ -577,11 +561,6 @@
 
   String get file => _context.path;
 
-  /// See [CompilationUnitImpl.invalidNodes].
-  List<AstNode> get invalidNodes {
-    return (unit as CompilationUnitImpl).invalidNodes;
-  }
-
   AstNode get node => _context._node;
 
   ResourceProvider get resourceProvider => unitResult.session.resourceProvider;
@@ -594,15 +573,6 @@
 
   AnalysisSessionHelper get sessionHelper => _context._sessionHelper;
 
-  bool get strictCasts {
-    var file = _context.dartFixContext?.resolvedResult.file;
-    // TODO(pq): can this ever happen?
-    if (file == null) return false;
-    var analysisOptions = _context._unitResult.session.analysisContext
-        .getAnalysisOptionsForFile(file) as AnalysisOptionsImpl;
-    return analysisOptions.strictCasts;
-  }
-
   Token get token => _context._token;
 
   CompilationUnit get unit => _context._unitResult.unit;
@@ -611,16 +581,12 @@
 
   CorrectionUtils get utils => _context._utils;
 
-  /// Configure this producer based on the [context].
+  /// Configures this producer based on the [context].
   @mustCallSuper
   void configure(CorrectionProducerContext<T> context) {
     _context = context;
   }
 
-  /// Returns the text that should be displayed to users when referring to the
-  /// given [type].
-  String displayStringForType(DartType type) => type.getDisplayString();
-
   CodeStyleOptions getCodeStyleOptions(File file) =>
       sessionHelper.session.analysisContext
           .getAnalysisOptionsForFile(file)
@@ -650,19 +616,17 @@
   }
 
   /// Returns the text of the given [range] in the unit.
-  String getRangeText(SourceRange range) {
-    return utils.getRangeText(range);
-  }
+  String getRangeText(SourceRange range) => utils.getRangeText(range);
 
   /// Returns the mapping from a library (that is available to this context) to
   /// a top-level declaration that is exported (not necessary declared) by this
-  /// library, and has the requested base name. For getters and setters the
-  /// corresponding top-level variable is returned.
+  /// library, and has the requested base name.
+  ///
+  /// For getters and setters the corresponding top-level variable is returned.
   Future<Map<LibraryElement, Element>> getTopLevelDeclarations(
     String baseName,
-  ) {
-    return _context.dartFixContext!.getTopLevelDeclarations(baseName);
-  }
+  ) =>
+      _context.dartFixContext!.getTopLevelDeclarations(baseName);
 
   /// Returns whether the selection covers an operator of the given
   /// [binaryExpression].
@@ -686,73 +650,9 @@
     return false;
   }
 
-  /// Return libraries with extensions that declare non-static public
+  /// Returns libraries with extensions that declare non-static public
   /// extension members with the [memberName].
   Stream<LibraryElement> librariesWithExtensions(String memberName) {
     return _context.dartFixContext!.librariesWithExtensions(memberName);
   }
-
-  /// Return `true` if the given [node] is in a location where an implicit
-  /// constructor invocation would be allowed.
-  bool mightBeImplicitConstructor(AstNode node) {
-    if (node is SimpleIdentifier) {
-      var parent = node.parent;
-      if (parent is MethodInvocation) {
-        return parent.realTarget == null;
-      }
-    }
-    return false;
-  }
-
-  /// If the [node] might be a type name, return its name.
-  String? nameOfType(AstNode node) {
-    if (node is SimpleIdentifier) {
-      var name = node.name;
-      if (node.parent is NamedType || _isNameOfType(name)) {
-        return name;
-      }
-    }
-    return null;
-  }
-
-  /// Return `true` if the given [expression] should be wrapped with parenthesis
-  /// when we want to use it as operand of a logical `and` expression.
-  bool shouldWrapParenthesisBeforeAnd(Expression expression) {
-    if (expression is BinaryExpression) {
-      var binary = expression;
-      var precedence = binary.operator.type.precedence;
-      return precedence < TokenClass.LOGICAL_AND_OPERATOR.precedence;
-    }
-    return false;
-  }
-
-  /// Return `true` if the [name] is capitalized.
-  bool _isNameOfType(String name) {
-    if (name.isEmpty) {
-      return false;
-    }
-    var firstLetter = name.substring(0, 1);
-    if (firstLetter.toUpperCase() != firstLetter) {
-      return false;
-    }
-    return true;
-  }
-}
-
-extension DartFileEditBuilderExtension on DartFileEditBuilder {
-  /// Add edits to the [builder] to remove any parentheses enclosing the
-  /// [expression].
-  // TODO(brianwilkerson): Consider moving this to DartFileEditBuilder.
-  void removeEnclosingParentheses(Expression expression) {
-    var precedence = getExpressionPrecedence(expression);
-    while (expression.parent is ParenthesizedExpression) {
-      var parenthesized = expression.parent as ParenthesizedExpression;
-      if (getExpressionParentPrecedence(parenthesized) > precedence) {
-        break;
-      }
-      addDeletion(range.token(parenthesized.leftParenthesis));
-      addDeletion(range.token(parenthesized.rightParenthesis));
-      expression = parenthesized;
-    }
-  }
 }
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 c264f2c..a256c59 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
@@ -48,8 +48,8 @@
         if (newType is InterfaceType ||
             newType is FunctionType ||
             newType is RecordType) {
-          _oldAnnotation = displayStringForType(typeNode.typeOrThrow);
-          _newAnnotation = displayStringForType(newType);
+          _oldAnnotation = typeNode.typeOrThrow.getDisplayString();
+          _newAnnotation = newType.getDisplayString();
           await builder.addDartFileEdit(file, (builder) {
             if (builder.canWriteType(newType)) {
               builder.addReplacement(range.node(typeNode), (builder) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/create_class.dart b/pkg/analysis_server/lib/src/services/correction/dart/create_class.dart
index 45a4a1b..417f37f 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/create_class.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/create_class.dart
@@ -55,14 +55,14 @@
       className = targetNode.name2.lexeme;
       requiresConstConstructor |= _requiresConstConstructor(targetNode);
     } else if (targetNode is SimpleIdentifier) {
-      className = nameOfType(targetNode);
+      className = targetNode.nameOfType;
       requiresConstConstructor |= _requiresConstConstructor(targetNode);
     } else if (targetNode is PrefixedIdentifier) {
       prefixElement = targetNode.prefix.staticElement;
       if (prefixElement == null) {
         return;
       }
-      className = nameOfType(targetNode.identifier);
+      className = targetNode.identifier.nameOfType;
     } else {
       return;
     }
@@ -159,3 +159,29 @@
     return false;
   }
 }
+
+extension on AstNode {
+  /// If this might be a type name, return its name.
+  String? get nameOfType {
+    var self = this;
+    if (self is SimpleIdentifier) {
+      var name = self.name;
+      if (self.parent is NamedType || _isNameOfType(name)) {
+        return name;
+      }
+    }
+    return null;
+  }
+
+  /// Return `true` if the [name] is capitalized.
+  static bool _isNameOfType(String name) {
+    if (name.isEmpty) {
+      return false;
+    }
+    var firstLetter = name.substring(0, 1);
+    if (firstLetter.toUpperCase() != firstLetter) {
+      return false;
+    }
+    return true;
+  }
+}
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/import_library.dart b/pkg/analysis_server/lib/src/services/correction/dart/import_library.dart
index 97f1604..b21c67b 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/import_library.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/import_library.dart
@@ -137,7 +137,7 @@
           ElementKind.MIXIN,
           ElementKind.TYPE_ALIAS,
         ]);
-      } else if (mightBeImplicitConstructor(targetNode)) {
+      } else if (targetNode.mightBeImplicitConstructor) {
         var typeName = (targetNode as SimpleIdentifier).name;
         await _importLibraryForElement(producers, typeName, const [
           ElementKind.CLASS,
@@ -147,7 +147,6 @@
     return producers;
   }
 
-  @override
   String? nameOfType(AstNode node) {
     var parent = node.parent;
     switch (node) {
@@ -584,3 +583,17 @@
     });
   }
 }
+
+extension on AstNode {
+  /// Whether this [AstNode] is in a location where an implicit constructor
+  /// invocation would be allowed.
+  bool get mightBeImplicitConstructor {
+    if (this is SimpleIdentifier) {
+      var parent = this.parent;
+      if (parent is MethodInvocation) {
+        return parent.realTarget == null;
+      }
+    }
+    return false;
+  }
+}
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/join_if_with_inner.dart b/pkg/analysis_server/lib/src/services/correction/dart/join_if_with_inner.dart
index f0b4744..b24b285 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/join_if_with_inner.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/join_if_with_inner.dart
@@ -47,10 +47,10 @@
     var innerCondition = innerIfStatement.expression;
     var targetConditionSource = utils.getNodeText(targetCondition);
     var innerConditionSource = utils.getNodeText(innerCondition);
-    if (shouldWrapParenthesisBeforeAnd(targetCondition)) {
+    if (targetCondition.shouldWrapParenthesisBeforeAnd) {
       targetConditionSource = '($targetConditionSource)';
     }
-    if (shouldWrapParenthesisBeforeAnd(innerCondition)) {
+    if (innerCondition.shouldWrapParenthesisBeforeAnd) {
       innerConditionSource = '($innerConditionSource)';
     }
     var condition = '$targetConditionSource && $innerConditionSource';
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/join_if_with_outer.dart b/pkg/analysis_server/lib/src/services/correction/dart/join_if_with_outer.dart
index 4a3a812..45dd05f 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/join_if_with_outer.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/join_if_with_outer.dart
@@ -53,10 +53,10 @@
     var outerCondition = outerIfStatement.expression;
     var targetConditionSource = utils.getNodeText(targetCondition);
     var outerConditionSource = utils.getNodeText(outerCondition);
-    if (shouldWrapParenthesisBeforeAnd(targetCondition)) {
+    if (targetCondition.shouldWrapParenthesisBeforeAnd) {
       targetConditionSource = '($targetConditionSource)';
     }
-    if (shouldWrapParenthesisBeforeAnd(outerCondition)) {
+    if (outerCondition.shouldWrapParenthesisBeforeAnd) {
       outerConditionSource = '($outerConditionSource)';
     }
     var condition = '$outerConditionSource && $targetConditionSource';
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/remove_constructor.dart b/pkg/analysis_server/lib/src/services/correction/dart/remove_constructor.dart
index fdb62ba..21b39f6 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/remove_constructor.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/remove_constructor.dart
@@ -4,8 +4,8 @@
 
 import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
-import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
+import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
@@ -51,8 +51,9 @@
       return null;
     }
 
+    var invalidNodes = (unit as CompilationUnitImpl).invalidNodes;
     for (var constructor in invalidNodes) {
-      if (constructor is ConstructorDeclaration) {
+      if (constructor is ConstructorDeclarationImpl) {
         if (range.node(constructor).contains(errorOffset)) {
           return constructor;
         }
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 fc8b40f..052dbcf 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
@@ -4,8 +4,10 @@
 
 import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analysis_server/src/services/correction/util.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
+import 'package:analyzer_plugin/utilities/change_builder/change_builder_dart.dart';
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
 
@@ -35,3 +37,20 @@
     });
   }
 }
+
+extension on DartFileEditBuilder {
+  /// Adds edits to this [DartFileEditBuilder] to remove any parentheses
+  /// enclosing the [expression].
+  void removeEnclosingParentheses(Expression expression) {
+    var precedence = getExpressionPrecedence(expression);
+    while (expression.parent is ParenthesizedExpression) {
+      var parenthesized = expression.parent as ParenthesizedExpression;
+      if (getExpressionParentPrecedence(parenthesized) > precedence) {
+        break;
+      }
+      addDeletion(range.token(parenthesized.leftParenthesis));
+      addDeletion(range.token(parenthesized.rightParenthesis));
+      expression = parenthesized;
+    }
+  }
+}
diff --git a/pkg/analysis_server/lib/src/utilities/extensions/ast.dart b/pkg/analysis_server/lib/src/utilities/extensions/ast.dart
index 35140cd..320ffaf 100644
--- a/pkg/analysis_server/lib/src/utilities/extensions/ast.dart
+++ b/pkg/analysis_server/lib/src/utilities/extensions/ast.dart
@@ -8,6 +8,7 @@
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/source/source.dart';
+import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/dart/ast/utilities.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/utilities/extensions/collection.dart';
@@ -350,6 +351,17 @@
     }
     return false;
   }
+
+  /// Whether this [Expression] should be wrapped with parentheses when we want
+  /// to use it as operand of a logical and-expression.
+  bool get shouldWrapParenthesisBeforeAnd {
+    var self = this;
+    if (self is! BinaryExpression) {
+      return false;
+    }
+    var precedence = self.operator.type.precedence;
+    return precedence < TokenClass.LOGICAL_AND_OPERATOR.precedence;
+  }
 }
 
 extension FunctionBodyExtension on FunctionBody {