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

pkg/compiler/lib/src/js_backend/codegen/codegen.dart

 // Copyright (c) 2014, 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.
 
 library code_generator;
 
 import 'glue.dart';
 
 import '../../tree_ir/tree_ir_nodes.dart' as tree_ir;
 import '../../tree_ir/tree_ir_nodes.dart' show BuiltinOperator;
@@ skipping 216 matching lines @@
     registry.registerStaticInvocation(target.declaration);
     if (target == glue.getInterceptorMethod) {
       // This generates a call to the specialized interceptor function, which
       // does not have a specialized element yet, but is emitted as a stub from
       // the emitter in [InterceptorStubGenerator].
       // TODO(karlklose): Either change [InvokeStatic] to take an [Entity]
       //   instead of an [Element] and model the getInterceptor functions as
       //   [Entity]s or add a specialized Tree-IR node for interceptor calls.
       registry.registerUseInterceptor();
       js.VariableUse interceptorLibrary = glue.getInterceptorLibrary();
-      return js.propertyCall(interceptorLibrary, selector.name, arguments);
+      return js.propertyCall(interceptorLibrary, js.string(selector.name),

[floitsch, 2015/06/22 17:43:43]

why is this just a string?

[herhut, 2015/06/23 13:26:30]

Because it is a broken abstraction. Selectors can only hold strings and the
cps_ir to tree converter puts the backend name of the interceptor to use into
the selector. However, selectors should only have front-end names in them.

asgerf@ was so nice to agree to fix the abstraction and then this will go away.

[asgerf, 2015/06/23 13:34:54]

Yeah that was broken. This CL should fix it: 
https://codereview.chromium.org/1204733002/

+                             arguments);
     } else {
       js.Expression elementAccess = glue.staticFunctionAccess(target);
       return new js.Call(elementAccess, arguments,
           sourceInformation: sourceInformation);
     }
   }
 
   @override
   js.Expression visitInvokeConstructor(tree_ir.InvokeConstructor node) {
     if (node.constant != null) return giveup(node);
@@ skipping 121 matching lines @@
       //
       //     checkSubtype(value, $isT, typeArgs, $asT)
       //     subtypeCast(value, $isT, typeArgs, $asT)
       //
       // Any of the last two arguments may be null if there are no type
       // arguments, and/or if no substitution is required.
       Element function = node.isTypeTest
           ? glue.getCheckSubtype()
           : glue.getSubtypeCast();
 
-      js.Expression isT = js.string(glue.getTypeTestTag(type));
+      js.Expression isT = js.quoteName(glue.getTypeTestTag(type));
 
       js.Expression typeArgumentArray = typeArguments.isNotEmpty
           ? new js.ArrayInitializer(typeArguments)
           : new js.LiteralNull();
 
       js.Expression asT = glue.hasStrictSubtype(clazz)
-          ? js.string(glue.getTypeSubstitutionTag(clazz))
+          ? js.quoteName(glue.getTypeSubstitutionTag(clazz))
           : new js.LiteralNull();
 
       return buildStaticHelperInvocation(
           function,
           <js.Expression>[value, isT, typeArgumentArray, asT]);
     } else if (type is TypeVariableType || type is FunctionType) {
       glue.registerIsCheck(type, registry);
 
       Element function = node.isTypeTest
           ? glue.getCheckSubtypeOfRuntimeType()
@@ skipping 206 matching lines @@
           <js.Expression>[instance, typeArguments]);
     } else {
       return instance;
     }
   }
 
   @override
   js.Expression visitCreateInvocationMirror(
       tree_ir.CreateInvocationMirror node) {
     js.Expression name = js.string(node.selector.name);
-    js.Expression internalName = js.string(glue.invocationName(node.selector));
+    js.Expression internalName =
+        js.quoteName(glue.invocationName(node.selector));
     js.Expression kind = js.number(node.selector.invocationMirrorKind);
     js.Expression arguments = new js.ArrayInitializer(
         visitExpressionList(node.arguments));
     js.Expression argumentNames = new js.ArrayInitializer(
         node.selector.namedArguments.map(js.string).toList(growable: false));
     return buildStaticHelperInvocation(glue.createInvocationMirrorMethod,
         [name, internalName, kind, arguments, argumentNames]);
   }
 
   @override
   js.Expression visitGetField(tree_ir.GetField node) {
-    return new js.PropertyAccess.field(
+    return new js.PropertyAccess(
         visitExpression(node.object),
         glue.instanceFieldPropertyName(node.field));
   }
 
   @override
   js.Assignment visitSetField(tree_ir.SetField node) {
     js.PropertyAccess field =
-        new js.PropertyAccess.field(
+        new js.PropertyAccess(
             visitExpression(node.object),
             glue.instanceFieldPropertyName(node.field));
     return new js.Assignment(field, visitExpression(node.value));
   }
 
   @override
   js.Expression visitGetStatic(tree_ir.GetStatic node) {
     assert(node.element is FieldElement || node.element is FunctionElement);
     if (node.element is FunctionElement) {
       // Tear off a method.
@@ skipping 103 matching lines @@
         return js.js("typeof # === 'number' && Math.floor(#) === #", args);
     }
   }
 
   visitFunctionExpression(tree_ir.FunctionExpression node) {
     // FunctionExpressions are currently unused.
     // We might need them if we want to emit raw JS nested functions.
     throw 'FunctionExpressions should not be used';
   }
 }