Implementation of extension override AST node

bwilkerson · commit-bot@chromium.org · commit 480337106ebe · 2019-07-03T14:01:07.000Z
Change-Id: Ia4249512c3bc14a995179328603fb847c2fe768e Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/107925 Reviewed-by: Phil Quitslund <pquitslund@google.com> Reviewed-by: Konstantin Shcheglov <scheglov@google.com> Commit-Queue: Brian Wilkerson <brianwilkerson@google.com>
diff --git a/pkg/analyzer/lib/dart/ast/ast.dart b/pkg/analyzer/lib/dart/ast/ast.dart
@@ -496,6 +496,8 @@ abstract class AstVisitor<R> {
 
   R visitExtensionDeclaration(ExtensionDeclaration node);
 
+  R visitExtensionOverride(ExtensionOverride node);
+
   R visitFieldDeclaration(FieldDeclaration node);
 
   R visitFieldFormalParameter(FieldFormalParameter node);
diff --git a/pkg/analyzer/lib/dart/ast/ast_factory.dart b/pkg/analyzer/lib/dart/ast/ast_factory.dart
@@ -342,7 +342,7 @@ abstract class AstFactory {
   /// Returns a newly created extends clause.
   ExtendsClause extendsClause(Token extendsKeyword, TypeName superclass);
 
-  /// Return a newly created extention declaration. The list of [typeParameters]
+  /// Return a newly created extension declaration. The list of [typeParameters]
   /// can be `null` if there are no type parameters.
   ExtensionDeclaration extensionDeclaration(
       {Comment comment,
@@ -356,6 +356,13 @@ abstract class AstFactory {
       List<ClassMember> members,
       Token rightBracket});
 
+  /// Return a newly created extension override. The list of [typeArguments]
+  /// can be `null` if there are no type arguments.
+  ExtensionOverride extensionOverride(
+      {@required Identifier extensionName,
+      TypeArgumentList typeArguments,
+      @required ArgumentList argumentList});
+
   /// Returns a newly created field declaration. Either or both of the [comment]
   /// and [metadata] can be `null` if the declaration does not have the
   /// corresponding attribute. The [staticKeyword] can be `null` if the field is
diff --git a/pkg/analyzer/lib/dart/ast/visitor.dart b/pkg/analyzer/lib/dart/ast/visitor.dart
@@ -277,6 +277,9 @@ class GeneralizingAstVisitor<R> implements AstVisitor<R> {
   R visitExtensionDeclaration(ExtensionDeclaration node) =>
       visitCompilationUnitMember(node);
 
+  @override
+  R visitExtensionOverride(ExtensionOverride node) => visitExpression(node);
+
   @override
   R visitFieldDeclaration(FieldDeclaration node) => visitClassMember(node);
 
@@ -843,6 +846,12 @@ class RecursiveAstVisitor<R> implements AstVisitor<R> {
     return null;
   }
 
+  @override
+  R visitExtensionOverride(ExtensionOverride node) {
+    node.visitChildren(this);
+    return null;
+  }
+
   @override
   R visitFieldDeclaration(FieldDeclaration node) {
     node.visitChildren(this);
@@ -1452,6 +1461,9 @@ class SimpleAstVisitor<R> implements AstVisitor<R> {
   @override
   R visitExtensionDeclaration(ExtensionDeclaration node) => null;
 
+  @override
+  R visitExtensionOverride(ExtensionOverride node) => null;
+
   @override
   R visitFieldDeclaration(FieldDeclaration node) => null;
 
@@ -1828,6 +1840,9 @@ class ThrowingAstVisitor<R> implements AstVisitor<R> {
   @override
   R visitExtensionDeclaration(ExtensionDeclaration node) => _throw(node);
 
+  @override
+  R visitExtensionOverride(ExtensionOverride node) => _throw(node);
+
   @override
   R visitFieldDeclaration(FieldDeclaration node) => _throw(node);
 
@@ -2420,6 +2435,14 @@ class TimedAstVisitor<T> implements AstVisitor<T> {
     return result;
   }
 
+  @override
+  T visitExtensionOverride(ExtensionOverride node) {
+    stopwatch.start();
+    T result = _baseVisitor.visitExtensionOverride(node);
+    stopwatch.stop();
+    return result;
+  }
+
   @override
   T visitFieldDeclaration(FieldDeclaration node) {
     stopwatch.start();
@@ -3196,6 +3219,9 @@ class UnifyingAstVisitor<R> implements AstVisitor<R> {
   @override
   R visitExtensionDeclaration(ExtensionDeclaration node) => visitNode(node);
 
+  @override
+  R visitExtensionOverride(ExtensionOverride node) => visitNode(node);
+
   @override
   R visitFieldDeclaration(FieldDeclaration node) => visitNode(node);
 
diff --git a/pkg/analyzer/lib/src/dart/ast/ast.dart b/pkg/analyzer/lib/src/dart/ast/ast.dart
@@ -3929,6 +3929,85 @@ class ExtensionDeclarationImpl extends CompilationUnitMemberImpl
   }
 }
 
+/// An override to force resolution to choose a member from a specific
+/// extension.
+///
+///    extensionOverride ::=
+///        [Identifier] [TypeArgumentList]? [ArgumentList]
+class ExtensionOverrideImpl extends ExpressionImpl
+    implements ExtensionOverride {
+  /// The list of arguments to the override. In valid code this will contain a
+  /// single argument, which evaluates to the object being extended.
+  ArgumentListImpl _argumentList;
+
+  /// The name of the extension being selected.
+  IdentifierImpl _extensionName;
+
+  /// The type arguments to be applied to the extension, or `null` if no type
+  /// arguments were provided.
+  TypeArgumentListImpl _typeArguments;
+
+  ExtensionOverrideImpl(IdentifierImpl extensionName,
+      TypeArgumentListImpl typeArguments, ArgumentListImpl argumentList) {
+    _extensionName = _becomeParentOf(extensionName);
+    _typeArguments = _becomeParentOf(typeArguments);
+    _argumentList = _becomeParentOf(argumentList);
+  }
+
+  @override
+  ArgumentList get argumentList => _argumentList;
+
+  void set argumentList(ArgumentList argumentList) {
+    _argumentList = _becomeParentOf(argumentList as ArgumentListImpl);
+  }
+
+  @override
+  Token get beginToken => _extensionName?.beginToken;
+
+  @override
+  Iterable<SyntacticEntity> get childEntities => new ChildEntities()
+    ..add(_extensionName)
+    ..add(_typeArguments)
+    ..add(_argumentList);
+
+  @override
+  Token get endToken => _argumentList?.endToken;
+
+  @override
+  Identifier get extensionName => _extensionName;
+
+  void set extensionName(Identifier extensionName) {
+    _extensionName = _becomeParentOf(extensionName as IdentifierImpl);
+  }
+
+  @override
+  Precedence get precedence => Precedence.postfix;
+
+  @override
+  TypeArgumentList get typeArguments => _typeArguments;
+
+  void set typeArguments(TypeArgumentList typeArguments) {
+    _typeArguments = _becomeParentOf(typeArguments as TypeArgumentListImpl);
+  }
+
+  @override
+  // TODO(brianwilkerson) Either implement this getter or remove it if it isn't
+  //  needed.
+  List<DartType> get typeArgumentTypes => null;
+
+  @override
+  E accept<E>(AstVisitor<E> visitor) {
+    return visitor.visitExtensionOverride(this);
+  }
+
+  @override
+  void visitChildren(AstVisitor visitor) {
+    _extensionName?.accept(visitor);
+    _typeArguments?.accept(visitor);
+    _argumentList?.accept(visitor);
+  }
+}
+
 /// The declaration of one or more fields of the same type.
 ///
 ///    fieldDeclaration ::=
diff --git a/pkg/analyzer/lib/src/dart/ast/ast_factory.dart b/pkg/analyzer/lib/src/dart/ast/ast_factory.dart
@@ -393,6 +393,13 @@ class AstFactoryImpl extends AstFactory {
           members,
           rightBracket);
 
+  @override
+  ExtensionOverride extensionOverride(
+          {@required Identifier extensionName,
+          TypeArgumentList typeArguments,
+          @required ArgumentList argumentList}) =>
+      ExtensionOverrideImpl(extensionName, typeArguments, argumentList);
+
   @override
   FieldDeclaration fieldDeclaration(
           Comment comment,
diff --git a/pkg/analyzer/lib/src/dart/ast/utilities.dart b/pkg/analyzer/lib/src/dart/ast/utilities.dart
@@ -461,6 +461,13 @@ class AstCloner implements AstVisitor<AstNode> {
           members: cloneNodeList(node.members),
           rightBracket: cloneToken(node.rightBracket));
 
+  @override
+  ExtensionOverride visitExtensionOverride(ExtensionOverride node) =>
+      astFactory.extensionOverride(
+          extensionName: cloneNode(node.extensionName),
+          typeArguments: cloneNode(node.typeArguments),
+          argumentList: cloneNode(node.argumentList));
+
   @override
   FieldDeclaration visitFieldDeclaration(FieldDeclaration node) =>
       astFactory.fieldDeclaration2(
@@ -1603,6 +1610,14 @@ class AstComparator implements AstVisitor<bool> {
         isEqualTokens(node.rightBracket, other.rightBracket);
   }
 
+  @override
+  bool visitExtensionOverride(ExtensionOverride node) {
+    ExtensionOverride other = _other as ExtensionOverride;
+    return isEqualNodes(node.extensionName, other.extensionName) &&
+        isEqualNodes(node.typeArguments, other.typeArguments) &&
+        isEqualNodes(node.argumentList, other.argumentList);
+  }
+
   @override
   bool visitFieldDeclaration(FieldDeclaration node) {
     FieldDeclaration other = _other as FieldDeclaration;
@@ -2855,6 +2870,13 @@ class IncrementalAstCloner implements AstVisitor<AstNode> {
           members: _cloneNodeList(node.members),
           rightBracket: _mapToken(node.rightBracket));
 
+  @override
+  ExtensionOverride visitExtensionOverride(ExtensionOverride node) =>
+      astFactory.extensionOverride(
+          extensionName: _cloneNode(node.extensionName),
+          typeArguments: _cloneNode(node.typeArguments),
+          argumentList: _cloneNode(node.argumentList));
+
   @override
   FieldDeclaration visitFieldDeclaration(FieldDeclaration node) =>
       astFactory.fieldDeclaration2(
@@ -4293,6 +4315,22 @@ class NodeReplacer implements AstVisitor<bool> {
     return visitNode(node);
   }
 
+  @override
+  bool visitExtensionOverride(ExtensionOverride node) {
+    if (identical(node.extensionName, _oldNode)) {
+      (node as ExtensionOverrideImpl).extensionName = _newNode as Identifier;
+      return true;
+    } else if (identical(node.typeArguments, _oldNode)) {
+      (node as ExtensionOverrideImpl).typeArguments =
+          _newNode as TypeArgumentList;
+      return true;
+    } else if (identical(node.argumentList, _oldNode)) {
+      (node as ExtensionOverrideImpl).argumentList = _newNode as ArgumentList;
+      return true;
+    }
+    return visitNode(node);
+  }
+
   @override
   bool visitFieldDeclaration(FieldDeclaration node) {
     if (identical(node.fields, _oldNode)) {
@@ -5664,6 +5702,15 @@ class ResolutionCopier implements AstVisitor<bool> {
     return false;
   }
 
+  @override
+  bool visitExtensionOverride(ExtensionOverride node) {
+    ExtensionOverride toNode = this._toNode as ExtensionOverride;
+    return _and(
+        _isEqualNodes(node.extensionName, toNode.extensionName),
+        _isEqualNodes(node.typeArguments, toNode.typeArguments),
+        _isEqualNodes(node.argumentList, toNode.argumentList));
+  }
+
   @override
   bool visitFieldDeclaration(FieldDeclaration node) {
     FieldDeclaration toNode = this._toNode as FieldDeclaration;
@@ -7247,6 +7294,13 @@ class ToSourceVisitor implements AstVisitor<void> {
     _visitToken(node.rightBracket);
   }
 
+  @override
+  void visitExtensionOverride(ExtensionOverride node) {
+    _visitNode(node.extensionName);
+    _visitNode(node.typeArguments);
+    _visitNode(node.argumentList);
+  }
+
   @override
   void visitFieldDeclaration(FieldDeclaration node) {
     _visitNodeListWithSeparatorAndSuffix(node.metadata, " ", " ");
@@ -8547,6 +8601,13 @@ class ToSourceVisitor2 implements AstVisitor<void> {
     safelyVisitToken(node.rightBracket);
   }
 
+  @override
+  void visitExtensionOverride(ExtensionOverride node) {
+    safelyVisitNode(node.extensionName);
+    safelyVisitNode(node.typeArguments);
+    safelyVisitNode(node.argumentList);
+  }
+
   @override
   void visitFieldDeclaration(FieldDeclaration node) {
     safelyVisitNodeListWithSeparatorAndSuffix(node.metadata, " ", " ");
diff --git a/pkg/analyzer/lib/src/generated/testing/ast_test_factory.dart b/pkg/analyzer/lib/src/generated/testing/ast_test_factory.dart
@@ -293,7 +293,7 @@ class AstTestFactory {
           List<Directive> directives,
           List<CompilationUnitMember> declarations,
           FeatureSet featureSet}) =>
-      astFactory.compilationUnit2(
+      astFactory.compilationUnit(
           beginToken: TokenFactory.tokenFromType(TokenType.EOF),
           scriptTag:
               scriptTag == null ? null : AstTestFactory.scriptTag(scriptTag),
@@ -505,6 +505,15 @@ class AstTestFactory {
           rightBracket:
               TokenFactory.tokenFromType(TokenType.CLOSE_CURLY_BRACKET));
 
+  static ExtensionOverride extensionOverride(
+          {@required Identifier extensionName,
+          TypeArgumentList typeArguments,
+          @required ArgumentList argumentList}) =>
+      astFactory.extensionOverride(
+          extensionName: extensionName,
+          typeArguments: typeArguments,
+          argumentList: argumentList);
+
   static FieldDeclaration fieldDeclaration(bool isStatic, Keyword keyword,
           TypeAnnotation type, List<VariableDeclaration> variables) =>
       astFactory.fieldDeclaration2(
diff --git a/pkg/analyzer/test/src/dart/ast/utilities_test.dart b/pkg/analyzer/test/src/dart/ast/utilities_test.dart
diff --git a/pkg/dev_compiler/lib/src/analyzer/code_generator.dart b/pkg/dev_compiler/lib/src/analyzer/code_generator.dart
