Add NativeEnqueuer to work with the Enqueuer.

sdk/lib/_internal/compiler/implementation/resolution/members.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 resolution;
 
 abstract class TreeElements {
   Element operator[](Node node);
   Selector getSelector(Send send);
   DartType getType(Node node);
@@ skipping 1717 matching lines @@
         // with the same arguments.
         Selector call = new Selector.callClosureFrom(selector);
         world.registerDynamicInvocation(call.name, call);
       } else if (target.impliesType()) {
         // We call 'call()' on a Type instance returned from the reference to a
         // class or typedef literal. We do not need to register this call as a
         // dynamic invocation, because we statically know what the target is.
       } else if (!selector.applies(target, compiler)) {
         warnArgumentMismatch(node, target);
       }
+
+      if (selector.name == const SourceString('JS')) {

[ngeoffray, 2012/11/08 08:18:01]

Note that the equality check must be done on the element.

[sra1, 2012/11/15 00:09:10]

Which element?

+        var argNodes = node.arguments;
+        if (!argNodes.isEmpty) {
+          resolveJsTypeParameter(argNodes.head, node);
+        }
+      }
     }
 
     // TODO(ngeoffray): Warn if target is null and the send is
     // unqualified.
     useElement(node, target);
     registerSend(selector, target);
     return node.isPropertyAccess ? target : null;
   }
 
   void warnArgumentMismatch(Send node, Element target) {
     // TODO(karlklose): we can be more precise about the reason of the
     // mismatch.
     warning(node.argumentsNode, MessageKind.INVALID_ARGUMENTS,
             [target.name]);
   }
 
+  void resolveJsTypeParameter(Node node, Node expression) {

[ngeoffray, 2012/11/08 08:18:01]

I would move this method to the native enqueuer.

[sra1, 2012/11/12 20:28:03]

Done.  I've moved everything except the lookup of a string in the scope.

+    // Resolve 'JS' type; mark as an instantiated native type.
+    //
+    // The type is currently a string.  We make an attempt at parsing the
+    // string.
+    //
+    // We will need the JS form to support union types and possible some other
+    // hints.  We could get the parser to resolve complex types like List<int>
+    // by using expressions that name classes, and a union by using a list
+    // literal.
+    //
+    //  JS(int, '#.foo', this);
+    //
+    //  JS([List<int>, bool], '...');   // Union of types.
+    //
+    //  JS([], '1');   // Type not expressable but harmless.
+    //
+    //  JS(['existing', Object], ...);  // Object, but not a fresh native one.
+
+    LiteralString typeStringLiteral = node.asLiteralString();
+    if (typeStringLiteral != null) {
+      String typeString = typeStringLiteral.dartString.slowToString();
+      if (! const {'': 1, 'var':1, 'void':1,
+                        //'bool':1, 'num':1, 'int':1, 'String':1
+                    }.containsKey(typeString)) {
+        Element element = resolveJSTypeString(typeString, node);
+        if (element != null) {
+          element.ensureResolved(compiler);
+          DartType type = element.computeType(compiler);
+          world.nativeEnqueuer.registerJSDartType(type, expression);

[ngeoffray, 2012/11/08 08:18:01]

Could this just be (native)enqueuer.registerInstantiatedClass ?

[sra1, 2012/11/12 20:28:03]

No, the matching is much more complex (subtypes, and I will want to add special
rules for some things.)

+        }
+      }
+      // Is there some way to decorate `node` with the type? With a union?
+    }
+  }
+
+  ClassElement resolveJSTypeString(String typeString, Node node) {
+    String typeName;
+    if (typeString.startsWith('new:')) {
+      typeName = typeString.substring(4);
+    } else {
+      typeName = typeString;
+    }
+    Element element = scope.lookup(new SourceString(typeName));
+    if (element == null) {
+      if (typeName == 'dynamic') return compiler.dynamicClass;
+      int index = typeName.indexOf('<');
+      if (index > 1) {
+        element = scope.lookup(new SourceString(typeName.substring(0, index)));
+      }
+      if (element == null) {
+        compiler.cancel(
+            "Type of JS expression '$typeName' not found",
+            node: node);
+        return;
+      }
+    }
+    if (element is! ClassElement) {
+      compiler.cancel(
+          "Type of JS expression '$typeName' not a class",
+          node: node);
+    } else {
+      return element;
+    }
+  }
+
   visitSendSet(SendSet node) {
     Element target = resolveSend(node);
     Element setter = target;
     Element getter = target;
     SourceString operatorName = node.assignmentOperator.source;
     String source = operatorName.stringValue;
     bool isComplex = !identical(source, '=');
     if (!Elements.isUnresolved(target)
         && target.kind == ElementKind.ABSTRACT_FIELD) {
       AbstractFieldElement field = target;
@@ skipping 1306 matching lines @@
     return e;
   }
 
   /// Assumed to be called by [resolveRedirectingFactory].
   Element visitReturn(Return node) {
     Node expression = node.expression;
     return finishConstructorReference(visit(expression),
                                       expression, expression);
   }
 }