Emit classes using ASTs

sdk/lib/_internal/compiler/implementation/js_backend/emitter_no_eval.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;
 
 class CodeEmitterNoEvalTask extends CodeEmitterTask {
   CodeEmitterNoEvalTask(Compiler compiler,
                         Namer namer,
                         bool generateSourceMap)
@@ skipping 70 matching lines @@
                 fieldNames.map((fieldName) =>
                     new js.ExpressionStatement(
                         new js.Assignment(
                             new js.This().dot(fieldName),
                             new js.VariableUse(fieldName)))))));
   }
 
   void emitBoundClosureClassHeader(String mangledName,
                                    String superName,
                                    List<String> fieldNames,
-                                   CodeBuffer buffer) {
-    buffer.add("$classesCollector.$mangledName = {'': ");
-    buffer.add(
-        js.prettyPrint(buildConstructor(mangledName, fieldNames), compiler));
-    buffer.add(",\n 'super': '$superName',\n");
+                                   ClassBuilder builder) {
+    builder.addProperty('', buildConstructor(mangledName, fieldNames));
+    builder.addProperty('super', js.string(superName));
   }
 
-  void emitClassConstructor(ClassElement classElement, CodeBuffer buffer) {
+  void emitClassConstructor(ClassElement classElement, ClassBuilder builder) {
     // Say we have a class A with fields b, c and d, where c needs a getter and
     // d needs both a getter and a setter. Then we produce:
     // - a constructor (directly into the given [buffer]):
     //   function A(b, c, d) { this.b = b, this.c = c, this.d = d; }
     // - getters and setters (stored in the [explicitGettersSetters] list):
     //   get$c : function() { return this.c; }
     //   get$d : function() { return this.d; }
     //   set$d : function(x) { this.d = x; }
     List<String> fields = <String>[];
     visitClassFields(classElement, (Element member,
                                     String name,
                                     String accessorName,
                                     bool needsGetter,
                                     bool needsSetter,
                                     bool needsCheckedSetter) {
       fields.add(name);
     });
     String constructorName = namer.safeName(classElement.name.slowToString());
-    buffer.add("'': ");
-    buffer.add(
-        js.prettyPrint(buildConstructor(constructorName, fields), compiler));
+
+    builder.addProperty('', buildConstructor(constructorName, fields));
   }
 
-  void emitSuper(String superName, CodeBuffer buffer) {
+  void emitSuper(String superName, ClassBuilder builder) {
     if (superName != '') {
-      buffer.add(",\n 'super': '$superName'");
+      builder.addProperty('super', js.string(superName));
     }
   }
 
   void emitClassFields(ClassElement classElement,
-                       CodeBuffer buffer,
-                       bool emitEndingComma,
+                       ClassBuilder builder,
                        { String superClass: "",
                          bool classIsNative: false}) {
-    if (emitEndingComma) buffer.add(', ');
   }
 
   bool get getterAndSetterCanBeImplementedByFieldSpec => false;
 }