dart2js: Use an abstract Name class for names in the generated JavaScript ast.

pkg/compiler/lib/src/js_backend/constant_emitter.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_backend;
 
 typedef jsAst.Expression _ConstantReferenceGenerator(ConstantValue constant);
 
+typedef jsAst.Expression _ConstantListGenerator(jsAst.Expression array);
+
 /**
  * Generates the JavaScript expressions for constants.
  *
  * It uses a given [constantReferenceGenerator] to reference nested constants
  * (if there are some). It is hence up to that function to decide which
  * constants should be inlined or not.
  */
 class ConstantEmitter
     implements ConstantValueVisitor<jsAst.Expression, Null> {
 
   // Matches blank lines, comment lines and trailing comments that can't be part
   // of a string.
   static final RegExp COMMENT_RE =
       new RegExp(r'''^ *(//.*)?\n|  *//[^''"\n]*$''' , multiLine: true);
 
   final Compiler compiler;
   final Namer namer;
   final _ConstantReferenceGenerator constantReferenceGenerator;
-  final jsAst.Template makeConstantListTemplate;
+  final _ConstantListGenerator makeConstantList;
 
   /**
    * The given [constantReferenceGenerator] function must, when invoked with a
    * constant, either return a reference or return its literal expression if it
    * can be inlined.
    */
   ConstantEmitter(
       this.compiler,
       this.namer,
       jsAst.Expression this.constantReferenceGenerator(ConstantValue constant),
-      this.makeConstantListTemplate);
+      this.makeConstantList);
 
   /**
    * Constructs a literal expression that evaluates to the constant. Uses a
    * canonical name unless the constant can be emitted multiple times (as for
    * numbers and strings).
    */
   jsAst.Expression generate(ConstantValue constant) {
     return _visit(constant);
   }
 
@@ skipping 104 matching lines @@
     writeJsonEscapedCharsOn(constant.primitiveValue.slowToString(), sb);
     return new jsAst.LiteralString('"$sb"');
   }
 
   @override
   jsAst.Expression visitList(ListConstantValue constant, [_]) {
     List<jsAst.Expression> elements = constant.entries
         .map(constantReferenceGenerator)
         .toList(growable: false);
     jsAst.ArrayInitializer array = new jsAst.ArrayInitializer(elements);
-    jsAst.Expression value = makeConstantListTemplate.instantiate([array]);
+    jsAst.Expression value = makeConstantList(array);
     return maybeAddTypeArguments(constant.type, value);
   }
 
   @override
   jsAst.Expression visitMap(JavaScriptMapConstant constant, [_]) {
     jsAst.Expression jsMap() {
       List<jsAst.Property> properties = <jsAst.Property>[];
       for (int i = 0; i < constant.length; i++) {
         StringConstantValue key = constant.keys[i];
         if (key.primitiveValue == JavaScriptMapConstant.PROTO_PROPERTY) {
@@ skipping 69 matching lines @@
 
   JavaScriptBackend get backend => compiler.backend;
 
   jsAst.PropertyAccess getHelperProperty(Element helper) {
     return backend.emitter.staticFunctionAccess(helper);
   }
 
   @override
   jsAst.Expression visitType(TypeConstantValue constant, [_]) {
     DartType type = constant.representedType;
-    String name = namer.runtimeTypeName(type.element);
-    jsAst.Expression typeName = new jsAst.LiteralString("'$name'");
+    jsAst.Name typeName = namer.runtimeTypeName(type.element);
     return new jsAst.Call(getHelperProperty(backend.getCreateRuntimeType()),
-                          [typeName]);
+                          [js.quoteName(typeName)]);
   }
 
   @override
   jsAst.Expression visitInterceptor(InterceptorConstantValue constant, [_]) {
     ClassElement interceptorClass = constant.dispatchedType.element;
     return backend.emitter.interceptorPrototypeAccess(interceptorClass);
   }
 
   @override
   jsAst.Expression visitSynthetic(SyntheticConstantValue constant, [_]) {
     switch (constant.kind) {
       case SyntheticConstantKind.DUMMY_INTERCEPTOR:
       case SyntheticConstantKind.EMPTY_VALUE:
         return new jsAst.LiteralNumber('0');
       case SyntheticConstantKind.TYPEVARIABLE_REFERENCE:
+      case SyntheticConstantKind.NAME:
         return constant.payload;
       default:
         compiler.internalError(NO_LOCATION_SPANNABLE,
                                "Unexpected DummyConstantKind ${constant.kind}");
         return null;
     }
   }
 
   @override
   jsAst.Expression visitConstructed(ConstructedConstantValue constant, [_]) {
@@ skipping 33 matching lines @@
                             [value, argumentList]);
     }
     return value;
   }
 
   @override
   jsAst.Expression visitDeferred(DeferredConstantValue constant, [_]) {
     return constantReferenceGenerator(constant.referenced);
   }
 }