[js_ast] adds Identifier that merges VariableDeclaration/Use and Parameter

lib/src/js/nodes.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of js_ast;
 
 abstract class NodeVisitor<T> {
   T visitProgram(Program node);
 
   T visitBlock(Block node);
@@ skipping 23 matching lines @@
   T visitVariableDeclarationList(VariableDeclarationList node);
   T visitAssignment(Assignment node);
   T visitVariableInitialization(VariableInitialization node);
   T visitConditional(Conditional cond);
   T visitNew(New node);
   T visitCall(Call node);
   T visitBinary(Binary node);
   T visitPrefix(Prefix node);
   T visitPostfix(Postfix node);
 
-  T visitVariableUse(VariableUse node);
+  T visitIdentifier(Identifier node);
   T visitThis(This node);
   T visitSuper(Super node);
-  T visitVariableDeclaration(VariableDeclaration node);
-  T visitParameter(Parameter node);
   T visitAccess(PropertyAccess node);
 
   T visitNamedFunction(NamedFunction node);
   T visitFun(Fun node);
   T visitArrowFun(ArrowFun node);
 
   T visitLiteralBool(LiteralBool node);
   T visitLiteralString(LiteralString node);
   T visitLiteralNumber(LiteralNumber node);
   T visitLiteralNull(LiteralNull node);
@@ skipping 14 matching lines @@
 
   T visitComment(Comment node);
   T visitCommentExpression(CommentExpression node);
 
   T visitInterpolatedExpression(InterpolatedExpression node);
   T visitInterpolatedLiteral(InterpolatedLiteral node);
   T visitInterpolatedParameter(InterpolatedParameter node);
   T visitInterpolatedSelector(InterpolatedSelector node);
   T visitInterpolatedStatement(InterpolatedStatement node);
   T visitInterpolatedMethod(InterpolatedMethod node);
-  T visitInterpolatedVariableDeclaration(InterpolatedVariableDeclaration node);
+  T visitInterpolatedIdentifier(InterpolatedIdentifier node);
 }
 
 class BaseVisitor<T> implements NodeVisitor<T> {
   T visitNode(Node node) {
     node.visitChildren(this);
     return null;
   }
 
   T visitProgram(Program node) => visitNode(node);
 
@@ skipping 20 matching lines @@
   T visitFunctionDeclaration(FunctionDeclaration node)
       => visitStatement(node);
   T visitLabeledStatement(LabeledStatement node) => visitStatement(node);
   T visitLiteralStatement(LiteralStatement node) => visitStatement(node);
 
   T visitCatch(Catch node) => visitNode(node);
   T visitCase(Case node) => visitNode(node);
   T visitDefault(Default node) => visitNode(node);
 
   T visitExpression(Expression node) => visitNode(node);
-  T visitVariableReference(VariableReference node) => visitExpression(node);
 
   T visitLiteralExpression(LiteralExpression node) => visitExpression(node);
   T visitVariableDeclarationList(VariableDeclarationList node)
       => visitExpression(node);
   T visitAssignment(Assignment node) => visitExpression(node);
   T visitVariableInitialization(VariableInitialization node) {
     if (node.value != null) {
       return visitAssignment(node);
     } else {
       return visitExpression(node);
     }
   }
   T visitConditional(Conditional node) => visitExpression(node);
   T visitNew(New node) => visitExpression(node);
   T visitCall(Call node) => visitExpression(node);
   T visitBinary(Binary node) => visitExpression(node);
   T visitPrefix(Prefix node) => visitExpression(node);
   T visitPostfix(Postfix node) => visitExpression(node);
   T visitAccess(PropertyAccess node) => visitExpression(node);
 
-  T visitVariableUse(VariableUse node) => visitVariableReference(node);
-  T visitVariableDeclaration(VariableDeclaration node)
-      => visitVariableReference(node);
-  T visitParameter(Parameter node) => visitVariableDeclaration(node);
-  T visitThis(This node) => visitParameter(node);
-  T visitSuper(Super node) => visitParameter(node);
+  T visitIdentifier(Identifier node) => visitExpression(node);
+  T visitThis(This node) => visitExpression(node);
+  T visitSuper(Super node) => visitExpression(node);
 
   T visitNamedFunction(NamedFunction node) => visitExpression(node);
   T visitFunctionExpression(FunctionExpression node) => visitExpression(node);
   T visitFun(Fun node) => visitFunctionExpression(node);
   T visitArrowFun(ArrowFun node) => visitFunctionExpression(node);
 
   T visitLiteral(Literal node) => visitExpression(node);
 
   T visitLiteralBool(LiteralBool node) => visitLiteral(node);
   T visitLiteralString(LiteralString node) => visitLiteral(node);
@@ skipping 19 matching lines @@
   T visitInterpolatedLiteral(InterpolatedLiteral node)
       => visitInterpolatedNode(node);
   T visitInterpolatedParameter(InterpolatedParameter node)
       => visitInterpolatedNode(node);
   T visitInterpolatedSelector(InterpolatedSelector node)
       => visitInterpolatedNode(node);
   T visitInterpolatedStatement(InterpolatedStatement node)
       => visitInterpolatedNode(node);
   T visitInterpolatedMethod(InterpolatedMethod node)
       => visitInterpolatedNode(node);
-  T visitInterpolatedVariableDeclaration(InterpolatedVariableDeclaration node)
+  T visitInterpolatedIdentifier(InterpolatedIdentifier node)
       => visitInterpolatedNode(node);
 
   // Ignore comments by default.
   T visitComment(Comment node) => null;
   T visitCommentExpression(CommentExpression node) => null;
 
   T visitAwait(Await node) => visitExpression(node);
   T visitDartYield(DartYield node) => visitStatement(node);
 }
 
@@ skipping 254 matching lines @@
   void visitChildren(NodeVisitor visitor) {
     body.accept(visitor);
     if (catchPart != null) catchPart.accept(visitor);
     if (finallyPart != null) finallyPart.accept(visitor);
   }
 
   Try _clone() => new Try(body, catchPart, finallyPart);
 }
 
 class Catch extends Node {
-  final VariableDeclaration declaration;
+  final Identifier declaration;
   final Block body;
 
   Catch(this.declaration, this.body);
 
   accept(NodeVisitor visitor) => visitor.visitCatch(this);
 
   void visitChildren(NodeVisitor visitor) {
     declaration.accept(visitor);
     body.accept(visitor);
   }
@@ skipping 44 matching lines @@
   accept(NodeVisitor visitor) => visitor.visitDefault(this);
 
   void visitChildren(NodeVisitor visitor) {
     body.accept(visitor);
   }
 
   Default _clone() => new Default(body);
 }
 
 class FunctionDeclaration extends Statement {
-  final VariableDeclaration name;
+  final Identifier name;
   final Fun function;
 
   FunctionDeclaration(this.name, this.function);
 
   accept(NodeVisitor visitor) => visitor.visitFunctionDeclaration(this);
 
   void visitChildren(NodeVisitor visitor) {
     name.accept(visitor);
     function.accept(visitor);
   }
@@ skipping 118 matching lines @@
     leftHandSide.accept(visitor);
     if (value != null) value.accept(visitor);
   }
 
   Assignment _clone() =>
       new Assignment.compound(leftHandSide, op, value);
 }
 
 class VariableInitialization extends Assignment {
   /** [value] may be null. */
-  VariableInitialization(VariableDeclaration declaration, Expression value)
+  VariableInitialization(Identifier declaration, Expression value)
       : super(declaration, value);
 
-  VariableDeclaration get declaration => leftHandSide;
+  Identifier get declaration => leftHandSide;
 
   accept(NodeVisitor visitor) => visitor.visitVariableInitialization(this);
 
   VariableInitialization _clone() =>
       new VariableInitialization(declaration, value);
 }
 
 class Conditional extends Expression {
   final Expression condition;
   final Expression then;
@@ skipping 126 matching lines @@
   Postfix(this.op, this.argument);
 
   accept(NodeVisitor visitor) => visitor.visitPostfix(this);
 
   Postfix _clone() => new Postfix(op, argument);
 
   void visitChildren(NodeVisitor visitor) {
     argument.accept(visitor);
   }
 
-
   int get precedenceLevel => UNARY;
 }
 
-abstract class VariableReference extends Expression {
+class Identifier extends Expression {
   final String name;
+  final bool allowRename;
 
-  VariableReference(this.name) {
+  Identifier(this.name, {this.allowRename: true}) {
     assert(_identifierRE.hasMatch(name));
   }
   static RegExp _identifierRE = new RegExp(r'^[A-Za-z_$][A-Za-z_$0-9]*$');
 
-  accept(NodeVisitor visitor);
+  Identifier _clone() =>
+      new Identifier(name, allowRename: allowRename);
+  accept(NodeVisitor visitor) => visitor.visitIdentifier(this);
   int get precedenceLevel => PRIMARY;
   void visitChildren(NodeVisitor visitor) {}
 }
 
-class VariableUse extends VariableReference {
-  VariableUse(String name) : super(name);
-
-  accept(NodeVisitor visitor) => visitor.visitVariableUse(this);
-  VariableUse _clone() => new VariableUse(name);
-
-  VariableUse asVariableUse() => this;
-
-  toString() => 'VariableUse($name)';
-}
-
-class VariableDeclaration extends VariableReference {
-  final bool allowRename;
-  VariableDeclaration(String name, {this.allowRename: true}) : super(name);
-
-  accept(NodeVisitor visitor) => visitor.visitVariableDeclaration(this);
-  VariableDeclaration _clone() => new VariableDeclaration(name);
-}
-
-class Parameter extends VariableDeclaration {
-  Parameter(String name) : super(name);
-
-  accept(NodeVisitor visitor) => visitor.visitParameter(this);
-  Parameter _clone() => new Parameter(name);
-}
-
-class This extends Parameter {
-  This() : super("this");
-
+class This extends Expression {
   accept(NodeVisitor visitor) => visitor.visitThis(this);
   This _clone() => new This();
+  int get precedenceLevel => PRIMARY;
+  void visitChildren(NodeVisitor visitor) {}
 }
 
 // `super` is more restricted in the ES6 spec, but for simplicity we accept
 // it anywhere that `this` is accepted.
-class Super extends Parameter {
-  Super() : super("super");
-
+class Super extends Expression {
   accept(NodeVisitor visitor) => visitor.visitSuper(this);
   Super _clone() => new Super();
+  int get precedenceLevel => PRIMARY;
+  void visitChildren(NodeVisitor visitor) {}
 }
 
 class NamedFunction extends Expression {
-  final VariableDeclaration name;
+  final Identifier name;
   final Fun function;
 
   NamedFunction(this.name, this.function);
 
   accept(NodeVisitor visitor) => visitor.visitNamedFunction(this);
 
   void visitChildren(NodeVisitor visitor) {
     name.accept(visitor);
     function.accept(visitor);
   }
   NamedFunction _clone() => new NamedFunction(name, function);
 
   int get precedenceLevel => CALL;
 }
 
 abstract class FunctionExpression extends Expression {
-  List<Parameter> get params;
+  List<Identifier> get params;
   get body; // Expression or block
 }
 
 class Fun extends FunctionExpression {
-  final List<Parameter> params;
+  final List<Identifier> params;
   final Block body;
   final AsyncModifier asyncModifier;
 
   Fun(this.params, this.body, {this.asyncModifier: const AsyncModifier.sync()});
 
   accept(NodeVisitor visitor) => visitor.visitFun(this);
 
   void visitChildren(NodeVisitor visitor) {
-    for (Parameter param in params) param.accept(visitor);
+    for (Identifier param in params) param.accept(visitor);
     body.accept(visitor);
   }
 
   Fun _clone() => new Fun(params, body, asyncModifier: asyncModifier);
 
   int get precedenceLevel => CALL;
 }
 
 class ArrowFun extends FunctionExpression {
-  final List<Parameter> params;
+  final List<Identifier> params;
   final body; // Expression or Block
 
   ArrowFun(this.params, this.body);
 
   accept(NodeVisitor visitor) => visitor.visitArrowFun(this);
 
   void visitChildren(NodeVisitor visitor) {
-    for (Parameter param in params) param.accept(visitor);
+    for (Identifier param in params) param.accept(visitor);
     body.accept(visitor);
   }
 
   ArrowFun _clone() => new ArrowFun(params, body);
 
   /// Ensure parens always get generated if necessary.
   // TODO(jmesserly): I'm not sure the printer is handling this correctly for
   // function() { ... } either.
   int get precedenceLevel => ASSIGNMENT;
 }
@@ skipping 141 matching lines @@
 
   ObjectInitializer _clone() => new ObjectInitializer(properties);
 
   int get precedenceLevel => PRIMARY;
 }
 
 class Property extends Node {
   final Expression name;
   final Expression value;
 
-  Property(this.name, this.value) {
-    assert(name is! VariableDeclaration);
-  }
+  Property(this.name, this.value);
 
   accept(NodeVisitor visitor) => visitor.visitProperty(this);
 
   void visitChildren(NodeVisitor visitor) {
     name.accept(visitor);
     value.accept(visitor);
   }
 
   Property _clone() => new Property(name, value);
 }
@@ skipping 50 matching lines @@
   final ClassExpression classExpr;
 
   ClassDeclaration(this.classExpr);
 
   accept(NodeVisitor visitor) => visitor.visitClassDeclaration(this);
   visitChildren(NodeVisitor visitor) => classExpr.accept(visitor);
   ClassDeclaration _clone() => new ClassDeclaration(classExpr);
 }
 
 class ClassExpression extends Expression {
-  final VariableDeclaration name;
+  final Identifier name;
   final Expression heritage; // Can be null.
   final List<Method> methods;
 
   ClassExpression(this.name, this.heritage, this.methods);
 
   accept(NodeVisitor visitor) => visitor.visitClassExpression(this);
 
   void visitChildren(NodeVisitor visitor) {
     name.accept(visitor);
     if (heritage != null) heritage.accept(visitor);
@@ skipping 55 matching lines @@
   final nameOrPosition;
 
   InterpolatedLiteral(this.nameOrPosition);
 
   accept(NodeVisitor visitor) => visitor.visitInterpolatedLiteral(this);
   void visitChildren(NodeVisitor visitor) {}
   InterpolatedLiteral _clone() => new InterpolatedLiteral(nameOrPosition);
 }
 
 class InterpolatedParameter extends Expression with InterpolatedNode
-    implements Parameter {
+    implements Identifier {
   final nameOrPosition;
 
   String get name { throw "InterpolatedParameter.name must not be invoked"; }
   bool get allowRename => false;
 
   InterpolatedParameter(this.nameOrPosition);
 
   accept(NodeVisitor visitor) => visitor.visitInterpolatedParameter(this);
   void visitChildren(NodeVisitor visitor) {}
   InterpolatedParameter _clone() => new InterpolatedParameter(nameOrPosition);
@@ skipping 37 matching lines @@
   int get precedenceLevel => PRIMARY;
   Expression get name => _unsupported;
   Expression get value => _unsupported;
   bool get isGetter => _unsupported;
   bool get isSetter => _unsupported;
   bool get isStatic => _unsupported;
   Fun get function => _unsupported;
   get _unsupported => throw '$runtimeType does not support this member.';
 }
 
-class InterpolatedVariableDeclaration extends Expression with InterpolatedNode
-    implements VariableDeclaration {
+class InterpolatedIdentifier extends Expression with InterpolatedNode
+    implements Identifier {
   final nameOrPosition;
 
-  InterpolatedVariableDeclaration(this.nameOrPosition);
+  InterpolatedIdentifier(this.nameOrPosition);
 
   accept(NodeVisitor visitor) =>
-      visitor.visitInterpolatedVariableDeclaration(this);
+      visitor.visitInterpolatedIdentifier(this);
   void visitChildren(NodeVisitor visitor) {}
-  InterpolatedVariableDeclaration _clone() =>
-      new InterpolatedVariableDeclaration(nameOrPosition);
+  InterpolatedIdentifier _clone() => new InterpolatedIdentifier(nameOrPosition);
 
   int get precedenceLevel => PRIMARY;
   String get name => throw '$runtimeType does not support this member.';
   bool get allowRename => false;
 }
 
 /**
  * [RegExpLiteral]s, despite being called "Literal", do not inherit from
  * [Literal]. Indeed, regular expressions in JavaScript have a side-effect and
  * are thus not in the same category as numbers or strings.
@@ skipping 57 matching lines @@
   final Expression expression;
 
   CommentExpression(this.comment, this.expression);
 
   int get precedenceLevel => PRIMARY;
   accept(NodeVisitor visitor) => visitor.visitCommentExpression(this);
   CommentExpression _clone() => new CommentExpression(comment, expression);
 
   void visitChildren(NodeVisitor visitor) => expression.accept(visitor);
 }