Support parsing of enums in dart2js.

sdk/lib/_internal/compiler/implementation/tree/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 tree;
 
 abstract class Visitor<R> {
   const Visitor();
 
   R visitNode(Node node);
 
   R visitBlock(Block node) => visitStatement(node);
   R visitBreakStatement(BreakStatement node) => visitGotoStatement(node);
   R visitCascade(Cascade node) => visitExpression(node);
   R visitCascadeReceiver(CascadeReceiver node) => visitExpression(node);
   R visitCaseMatch(CaseMatch node) => visitNode(node);
   R visitCatchBlock(CatchBlock node) => visitNode(node);
   R visitClassNode(ClassNode node) => visitNode(node);
   R visitCombinator(Combinator node) => visitNode(node);
   R visitConditional(Conditional node) => visitExpression(node);
   R visitContinueStatement(ContinueStatement node) => visitGotoStatement(node);
   R visitDoWhile(DoWhile node) => visitLoop(node);
   R visitEmptyStatement(EmptyStatement node) => visitStatement(node);
+  R visitEnum(Enum node) => visitNode(node);
   R visitExport(Export node) => visitLibraryDependency(node);
   R visitExpression(Expression node) => visitNode(node);
   R visitExpressionStatement(ExpressionStatement node) => visitStatement(node);
   R visitFor(For node) => visitLoop(node);
   R visitForIn(ForIn node) => visitLoop(node);
   R visitFunctionDeclaration(FunctionDeclaration node) => visitStatement(node);
   R visitFunctionExpression(FunctionExpression node) => visitExpression(node);
   R visitGotoStatement(GotoStatement node) => visitStatement(node);
   R visitIdentifier(Identifier node) => visitExpression(node);
   R visitIf(If node) => visitStatement(node);
@@ skipping 112 matching lines @@
   Cascade asCascade() => null;
   CascadeReceiver asCascadeReceiver() => null;
   CaseMatch asCaseMatch() => null;
   CatchBlock asCatchBlock() => null;
   ClassNode asClassNode() => null;
   Combinator asCombinator() => null;
   Conditional asConditional() => null;
   ContinueStatement asContinueStatement() => null;
   DoWhile asDoWhile() => null;
   EmptyStatement asEmptyStatement() => null;
+  Enum asEnum() => null;
   ErrorExpression asErrorExpression() => null;
   Export asExport() => null;
   Expression asExpression() => null;
   ExpressionStatement asExpressionStatement() => null;
   For asFor() => null;
   ForIn asForIn() => null;
   FunctionDeclaration asFunctionDeclaration() => null;
   FunctionExpression asFunctionExpression() => null;
   Identifier asIdentifier() => null;
   If asIf() => null;
@@ skipping 1678 matching lines @@
   Token getBeginToken() => importKeyword;
 
   Token getEndToken() {
     if (combinators != null) return combinators.getEndToken().next;
     if (prefix != null) return prefix.getEndToken().next;
     return uri.getEndToken().next;
   }
 }
 
 /**
+ * An `enum` declaration.
+ *
+ * An `enum` defines a number of named constants inside a non-extensible class
+ */
+class Enum extends Node {
+  /** The name of the enum class. */
+  final Identifier name;
+  /** The names of the enum constants. */
+  final NodeList names;
+  final Token enumToken;
+
+  Enum(this.enumToken, this.name, this.names);
+
+  Enum asEnum() => this;
+
+  accept(Visitor visitor) => visitor.visitEnum(this);
+
+  visitChildren(Visitor visitor) {
+    name.accept(visitor);
+    if (names != null) names.accept(visitor);
+  }
+
+  Token getBeginToken() => enumToken;
+  Token getEndToken() => names.getEndToken();
+}
+
+/**
  * An [:export:] library tag.
  *
  * An export tag is dependency on another library where the exported identifiers
  * are put into the export scope of the exporting library. The export scope is
  * not visible inside the library.
  */
 class Export extends LibraryDependency {
   final Token exportKeyword;
 
   Export(this.exportKeyword,
@@ skipping 316 matching lines @@
 
   // VariableDefinitions.
   get metadata => null;
   get type => null;
 
   // Typedef.
   get typeParameters => null;
   get formals => null;
   get typedefKeyword => null;
 }