[analyzer] Dot Shorthands: AST - DotShorthandInvocation and DotShorthandPropertyAccess.

This CL adds new nodes for the dot shorthands feature. These new nodes will be used, alongside a context type, to resolve to a method/constructor invocation or a static field/getter or tearoff.

Design decision for this CL made here: https://docs.google.com/document/d/1rJuwytXFyG9Ir9key146_hAa7uhEXk4Otqd_3RpSg8A/edit?usp=sharing&resourcekey=0-hRydkMfiTwDEwsX3fN4taQ

Bug: #59835
Change-Id: Iab78bd9e55e488656d1138b1d5d6fc5c9ed64bde
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/418201
Reviewed-by: Brian Wilkerson <[email protected]>
Reviewed-by: Paul Berry <[email protected]>
Commit-Queue: Kallen Tu <[email protected]>

Author: kallentu

pkg/analyzer/api.txt

@@ -379,6 +379,8 @@ package:analyzer/dart/ast/ast.dart:
     visitDeclaredVariablePattern (method: R? Function(DeclaredVariablePattern))
     visitDefaultFormalParameter (method: R? Function(DefaultFormalParameter))
     visitDoStatement (method: R? Function(DoStatement))
+    visitDotShorthandInvocation (method: R? Function(DotShorthandInvocation))
+    visitDotShorthandPropertyAccess (method: R? Function(DotShorthandPropertyAccess))
     visitDottedName (method: R? Function(DottedName))
     visitDoubleLiteral (method: R? Function(DoubleLiteral))
     visitEmptyFunctionBody (method: R? Function(EmptyFunctionBody))
@@ -733,6 +735,12 @@ package:analyzer/dart/ast/ast.dart:
     rightParenthesis (getter: Token)
     semicolon (getter: Token)
     whileKeyword (getter: Token)
+  DotShorthandInvocation (class extends InvocationExpression, experimental):
+    memberName (getter: SimpleIdentifier)
+    period (getter: Token)
+  DotShorthandPropertyAccess (class extends Expression, experimental):
+    period (getter: Token)
+    propertyName (getter: Token)
   DottedName (class extends Object implements AstNode):
     components (getter: NodeList<SimpleIdentifier>)
   DoubleLiteral (class extends Object implements Literal):
@@ -1943,6 +1951,8 @@ package:analyzer/dart/ast/visitor.dart:
     visitDefaultFormalParameter (method: R? Function(DefaultFormalParameter))
     visitDirective (method: R? Function(Directive))
     visitDoStatement (method: R? Function(DoStatement))
+    visitDotShorthandInvocation (method: R? Function(DotShorthandInvocation))
+    visitDotShorthandPropertyAccess (method: R? Function(DotShorthandPropertyAccess))
     visitDottedName (method: R? Function(DottedName))
     visitDoubleLiteral (method: R? Function(DoubleLiteral))
     visitEmptyFunctionBody (method: R? Function(EmptyFunctionBody))
@@ -2139,6 +2149,8 @@ package:analyzer/dart/ast/visitor.dart:
     visitDeclaredVariablePattern (method: R? Function(DeclaredVariablePattern))
     visitDefaultFormalParameter (method: R? Function(DefaultFormalParameter))
     visitDoStatement (method: R? Function(DoStatement))
+    visitDotShorthandInvocation (method: R? Function(DotShorthandInvocation))
+    visitDotShorthandPropertyAccess (method: R? Function(DotShorthandPropertyAccess))
     visitDottedName (method: R? Function(DottedName))
     visitDoubleLiteral (method: R? Function(DoubleLiteral))
     visitEmptyFunctionBody (method: R? Function(EmptyFunctionBody))
@@ -2313,6 +2325,8 @@ package:analyzer/dart/ast/visitor.dart:
     visitDeclaredVariablePattern (method: R? Function(DeclaredVariablePattern))
     visitDefaultFormalParameter (method: R? Function(DefaultFormalParameter))
     visitDoStatement (method: R? Function(DoStatement))
+    visitDotShorthandInvocation (method: R? Function(DotShorthandInvocation))
+    visitDotShorthandPropertyAccess (method: R? Function(DotShorthandPropertyAccess))
     visitDottedName (method: R? Function(DottedName))
     visitDoubleLiteral (method: R? Function(DoubleLiteral))
     visitEmptyFunctionBody (method: R? Function(EmptyFunctionBody))
@@ -2487,6 +2501,8 @@ package:analyzer/dart/ast/visitor.dart:
     visitDeclaredVariablePattern (method: R? Function(DeclaredVariablePattern))
     visitDefaultFormalParameter (method: R? Function(DefaultFormalParameter))
     visitDoStatement (method: R? Function(DoStatement))
+    visitDotShorthandInvocation (method: R? Function(DotShorthandInvocation))
+    visitDotShorthandPropertyAccess (method: R? Function(DotShorthandPropertyAccess))
     visitDottedName (method: R? Function(DottedName))
     visitDoubleLiteral (method: R? Function(DoubleLiteral))
     visitEmptyFunctionBody (method: R? Function(EmptyFunctionBody))
@@ -2662,6 +2678,8 @@ package:analyzer/dart/ast/visitor.dart:
     visitDeclaredVariablePattern (method: T? Function(DeclaredVariablePattern))
     visitDefaultFormalParameter (method: T? Function(DefaultFormalParameter))
     visitDoStatement (method: T? Function(DoStatement))
+    visitDotShorthandInvocation (method: T? Function(DotShorthandInvocation))
+    visitDotShorthandPropertyAccess (method: T? Function(DotShorthandPropertyAccess))
     visitDottedName (method: T? Function(DottedName))
     visitDoubleLiteral (method: T? Function(DoubleLiteral))
     visitEmptyFunctionBody (method: T? Function(EmptyFunctionBody))
@@ -2836,6 +2854,8 @@ package:analyzer/dart/ast/visitor.dart:
     visitDeclaredVariablePattern (method: R? Function(DeclaredVariablePattern))
     visitDefaultFormalParameter (method: R? Function(DefaultFormalParameter))
     visitDoStatement (method: R? Function(DoStatement))
+    visitDotShorthandInvocation (method: R? Function(DotShorthandInvocation))
+    visitDotShorthandPropertyAccess (method: R? Function(DotShorthandPropertyAccess))
     visitDottedName (method: R? Function(DottedName))
     visitDoubleLiteral (method: R? Function(DoubleLiteral))
     visitEmptyFunctionBody (method: R? Function(EmptyFunctionBody))

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

@@ -92,6 +92,8 @@ export 'package:analyzer/src/dart/ast/ast.dart'
         DefaultFormalParameter,
         Directive,
         DoStatement,
+        DotShorthandInvocation,
+        DotShorthandPropertyAccess,
         DottedName,
         DoubleLiteral,
         EmptyFunctionBody,

pkg/analyzer/lib/dart/ast/visitor.dart

@@ -279,6 +279,14 @@ class GeneralizingAstVisitor<R> implements AstVisitor<R> {
   @override
   R? visitDoStatement(DoStatement node) => visitStatement(node);
 
+  @override
+  R? visitDotShorthandInvocation(DotShorthandInvocation node) =>
+      visitExpression(node);
+
+  @override
+  R? visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node) =>
+      visitExpression(node);
+
   @override
   R? visitDottedName(DottedName node) => visitNode(node);
 
@@ -1035,6 +1043,18 @@ class RecursiveAstVisitor<R> implements AstVisitor<R> {
     return null;
   }
 
+  @override
+  R? visitDotShorthandInvocation(DotShorthandInvocation node) {
+    node.visitChildren(this);
+    return null;
+  }
+
+  @override
+  R? visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node) {
+    node.visitChildren(this);
+    return null;
+  }
+
   @override
   R? visitDottedName(DottedName node) {
     node.visitChildren(this);
@@ -1965,6 +1985,12 @@ class SimpleAstVisitor<R> implements AstVisitor<R> {
   @override
   R? visitDoStatement(DoStatement node) => null;
 
+  @override
+  R? visitDotShorthandInvocation(DotShorthandInvocation node) => null;
+
+  @override
+  R? visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node) => null;
+
   @override
   R? visitDottedName(DottedName node) => null;
 
@@ -2508,6 +2534,13 @@ class ThrowingAstVisitor<R> implements AstVisitor<R> {
   @override
   R? visitDoStatement(DoStatement node) => _throw(node);
 
+  @override
+  R? visitDotShorthandInvocation(DotShorthandInvocation node) => _throw(node);
+
+  @override
+  R? visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node) =>
+      _throw(node);
+
   @override
   R? visitDottedName(DottedName node) => _throw(node);
 
@@ -3266,6 +3299,22 @@ class TimedAstVisitor<T> implements AstVisitor<T> {
     return result;
   }
 
+  @override
+  T? visitDotShorthandInvocation(DotShorthandInvocation node) {
+    stopwatch.start();
+    T? result = _baseVisitor.visitDotShorthandInvocation(node);
+    stopwatch.stop();
+    return result;
+  }
+
+  @override
+  T? visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node) {
+    stopwatch.start();
+    T? result = _baseVisitor.visitDotShorthandPropertyAccess(node);
+    stopwatch.stop();
+    return result;
+  }
+
   @override
   T? visitDottedName(DottedName node) {
     stopwatch.start();
@@ -4472,6 +4521,14 @@ class UnifyingAstVisitor<R> implements AstVisitor<R> {
   @override
   R? visitDoStatement(DoStatement node) => visitNode(node);
 
+  @override
+  R? visitDotShorthandInvocation(DotShorthandInvocation node) =>
+      visitNode(node);
+
+  @override
+  R? visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node) =>
+      visitNode(node);
+
   @override
   R? visitDottedName(DottedName node) => visitNode(node);
 

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

@@ -1283,6 +1283,10 @@ abstract class AstVisitor<R> {
 
   R? visitDoStatement(DoStatement node);
 
+  R? visitDotShorthandInvocation(DotShorthandInvocation node);
+
+  R? visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node);
+
   R? visitDottedName(DottedName node);
 
   R? visitDoubleLiteral(DoubleLiteral node);
@@ -5392,6 +5396,140 @@ final class DoStatementImpl extends StatementImpl implements DoStatement {
   }
 }
 
+/// A node that represents a dot shorthand static method or constructor
+/// invocation.
+///
+/// For example, `.parse('42')`.
+///
+///    dotShorthandHead ::=
+///        '.' [SimpleIdentifier] [TypeArgumentList]? [ArgumentList]
+@experimental
+@AnalyzerPublicApi(message: 'exported by lib/dart/ast/ast.dart')
+abstract final class DotShorthandInvocation extends InvocationExpression {
+  /// The name of the constructor or static method invocation.
+  SimpleIdentifier get memberName;
+
+  /// The token representing the period.
+  Token get period;
+}
+
+final class DotShorthandInvocationImpl extends InvocationExpressionImpl
+    implements DotShorthandInvocation {
+  @override
+  final Token period;
+
+  SimpleIdentifierImpl _memberName;
+
+  /// Initializes a newly created dot shorthand invocation.
+  DotShorthandInvocationImpl({
+    required this.period,
+    required SimpleIdentifierImpl memberName,
+    required super.typeArguments,
+    required super.argumentList,
+  }) : _memberName = memberName {
+    _becomeParentOf(_memberName);
+  }
+
+  @override
+  Token get beginToken => period;
+
+  @override
+  Token get endToken => argumentList.endToken;
+
+  @override
+  ExpressionImpl get function => memberName;
+
+  @override
+  SimpleIdentifierImpl get memberName => _memberName;
+
+  set memberName(SimpleIdentifierImpl identifier) {
+    _memberName = _becomeParentOf(identifier);
+  }
+
+  @override
+  Precedence get precedence => Precedence.postfix;
+
+  @override
+  ChildEntities get _childEntities => ChildEntities()
+    ..addToken('period', period)
+    ..addNode('memberName', memberName)
+    ..addNode('typeArguments', typeArguments)
+    ..addNode('argumentList', argumentList);
+
+  @override
+  E? accept<E>(AstVisitor<E> visitor) =>
+      visitor.visitDotShorthandInvocation(this);
+
+  @override
+  void resolveExpression(ResolverVisitor resolver, TypeImpl contextType) {
+    resolver.visitDotShorthandInvocation(this, contextType: contextType);
+  }
+
+  @override
+  void visitChildren(AstVisitor visitor) {
+    memberName.accept(visitor);
+    typeArguments?.accept(visitor);
+    argumentList.accept(visitor);
+  }
+}
+
+/// A node that represents a dot shorthand property access of a field or a
+/// static getter.
+///
+/// For example, `.zero`.
+///
+///    dotShorthandHead ::= '.' [SimpleIdentifier]
+@experimental
+@AnalyzerPublicApi(message: 'exported by lib/dart/ast/ast.dart')
+abstract final class DotShorthandPropertyAccess extends Expression {
+  /// The token representing the period.
+  Token get period;
+
+  /// The name of the property being accessed.
+  Token get propertyName;
+}
+
+final class DotShorthandPropertyAccessImpl extends ExpressionImpl
+    implements DotShorthandPropertyAccess {
+  @override
+  final Token period;
+
+  @override
+  final Token propertyName;
+
+  /// Initializes a newly created dot shorthand property access.
+  DotShorthandPropertyAccessImpl({
+    required this.period,
+    required this.propertyName,
+  });
+
+  @override
+  Token get beginToken => period;
+
+  @override
+  Token get endToken => propertyName;
+
+  @override
+  Precedence get precedence => Precedence.postfix;
+
+  @override
+  ChildEntities get _childEntities => ChildEntities()
+    ..addToken('period', period)
+    ..addToken('propertyName', propertyName);
+
+  @override
+  E? accept<E>(AstVisitor<E> visitor) =>
+      visitor.visitDotShorthandPropertyAccess(this);
+
+  @override
+  void resolveExpression(ResolverVisitor resolver, TypeImpl contextType) {
+    resolver.visitDotShorthandPropertyAccess(this, contextType: contextType);
+  }
+
+  @override
+  void visitChildren(AstVisitor visitor) {}
+}
+
 /// A dotted name, used in a configuration within an import or export directive.
 ///
 ///    dottedName ::=
@@ -10838,8 +10976,8 @@ final class InterpolationStringImpl extends InterpolationElementImpl
 
 /// The invocation of a function or method.
 ///
-/// This will either be a [FunctionExpressionInvocation] or a
-/// [MethodInvocation].
+/// This will either be a [FunctionExpressionInvocation], [MethodInvocation],
+/// or a [DotShorthandInvocation].
 @AnalyzerPublicApi(message: 'exported by lib/dart/ast/ast.dart')
 abstract final class InvocationExpression implements Expression {
   /// The list of arguments to the method.

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

@@ -348,6 +348,20 @@ class ToSourceVisitor implements AstVisitor<void> {
     sink.write(');');
   }
 
+  @override
+  void visitDotShorthandInvocation(DotShorthandInvocation node) {
+    _visitToken(node.period);
+    _visitNode(node.memberName);
+    _visitNode(node.typeArguments);
+    _visitNode(node.argumentList);
+  }
+
+  @override
+  void visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node) {
+    _visitToken(node.period);
+    _visitToken(node.propertyName);
+  }
+
   @override
   void visitDottedName(DottedName node) {
     _visitNodeList(node.components, separator: '.');