Generative constructor factories for native objects

sdk/lib/_internal/compiler/implementation/ssa/codegen.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 ssa;
 
 class SsaCodeGeneratorTask extends CompilerTask {
 
   final JavaScriptBackend backend;
 
@@ skipping 1778 matching lines @@
 
     // TODO(sra): Tell world.nativeEnqueuer about the types created here.
     registerForeignTypes(node);
   }
 
   visitForeignNew(HForeignNew node) {
     String jsClassReference = backend.namer.isolateAccess(node.element);
     List<js.Expression> arguments = visitArguments(node.inputs, start: 0);
     // TODO(floitsch): jsClassReference is an Access. We shouldn't treat it
     // as if it was a string.
-    push(new js.New(new js.VariableUse(jsClassReference), arguments), node);
+    js.Expression constructor = new js.VariableUse(jsClassReference);

[ngeoffray, 2013/10/17 09:08:59]

Why this change?

[sra1, 2013/10/18 04:09:32]

It can be changed back.  Original formulation called the constructor instead of
new-ing it, but that had the bad effect of null-ing out native fields.

+    push(new js.New(constructor, arguments), node);
     registerForeignTypes(node);
     if (node.instantiatedTypes == null) {
       return;
     }
     node.instantiatedTypes.forEach((type) {
       world.registerInstantiatedType(type, work.resolutionTree);
     });
   }
 
   js.Expression newLiteralBool(bool value) {
     if (compiler.enableMinification) {
       // Use !0 for true, !1 for false.
       return new js.Prefix("!", new js.LiteralNumber(value ? "0" : "1"));
     } else {
       return new js.LiteralBool(value);
     }
   }
 
   void generateConstant(Constant constant) {
     if (constant.isFunction()) {
       FunctionConstant function = constant;
       world.registerStaticUse(function.element);
     }
+    if (constant.isType()) {
+      // If the type is a web component, we need to ensure the constructors are

[ngeoffray, 2013/10/17 09:08:59]

There's no check of 'web component' here. Maybe you should check it here and
assert in 'regiterEscapingConstructorsOfClass'.

[sra1, 2013/10/18 04:09:32]

We now register the constant with the backend.

+      // available to 'upgrade' the native object.
+      TypeConstant type = constant;
+      Element element = type.representedType.element;
+      if (element != null && element.isClass()) {
+        backend.registerEscapingConstructorsOfClass(element, world);
+      }
+    }
     push(backend.emitter.constantReference(constant));
   }
 
   visitConstant(HConstant node) {
     assert(isGenerateAtUseSite(node));
     generateConstant(node.constant);
 
     backend.registerCompileTimeConstant(node.constant, work.resolutionTree);
     compiler.constantHandler.addCompileTimeConstantForEmission(node.constant);
   }
@@ skipping 1210 matching lines @@
   if (leftType.canBeNull() && rightType.canBeNull()) {
     if (left.isConstantNull() || right.isConstantNull() ||
         (leftType.isPrimitive(compiler) && leftType == rightType)) {
       return '==';
     }
     return null;
   } else {
     return '===';
   }
 }