Support isExternal method on MethodMirror in the Dart VM. Not really intended for public consumptio…

sdk/lib/js/dartium/js_dartium.dart

Index: sdk/lib/js/dartium/js_dartium.dart
diff --git a/sdk/lib/js/dartium/js_dartium.dart b/sdk/lib/js/dartium/js_dartium.dart
index eeecd93c492709ee57c817d4bd7f8e2631671933..60dac4bf73239c46cf48c3a4e5336234a8af1620 100644
--- a/sdk/lib/js/dartium/js_dartium.dart
+++ b/sdk/lib/js/dartium/js_dartium.dart
@@ -104,8 +104,8 @@ final _allowedMethods = new Map<Symbol, _DeclarationSet>();
 final _allowedGetters = new Map<Symbol, _DeclarationSet>();
 final _allowedSetters = new Map<Symbol, _DeclarationSet>();
 
-final _jsInterfaceTypes = new Set<Type>();
-Iterable<Type> get jsInterfaceTypes => _jsInterfaceTypes;
+final _jsInterfaceTypes = new Set<mirrors.ClassMirror>();
+Iterable<mirrors.ClassMirror> get jsInterfaceTypes => _jsInterfaceTypes;
 
 /// A collection of methods where all methods have the same name.
 /// This class is intended to optimize whether a specific invocation is
@@ -213,7 +213,6 @@ void registerJsInterfaces([List<Type> classes]) {
 
 void _registerJsInterfaces(List<Type> classes) {
   for (Type type in classes) {
-    if (!_jsInterfaceTypes.add(type)) continue; // Already registered.
     mirrors.ClassMirror typeMirror = mirrors.reflectType(type);
     typeMirror.declarations.forEach((symbol, declaration) {
       if (declaration is mirrors.MethodMirror ||
@@ -274,6 +273,20 @@ String _getJsName(mirrors.DeclarationMirror mirror) {
   return null;
 }
 
+bool _isAnonymousClass(mirrors.ClassMirror mirror) {
+  for (var annotation in mirror.metadata) {
+    if (mirrors.MirrorSystem.getName(annotation.type.simpleName) == "_Anonymous") {
+      mirrors.LibraryMirror library = annotation.type.owner;
+      var uri = library.uri;
+      // make sure the annotation is from package://js
+      if (uri.scheme == 'package' && uri.path == 'js/js.dart') {
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
 bool _hasJsName(mirrors.DeclarationMirror mirror) =>
   _getJsName(mirror) != null;
 
@@ -302,8 +315,10 @@ String _accessJsPath(String path) =>
 
 @Deprecated("Internal Use Only")
 void addMemberHelper(mirrors.MethodMirror declaration, String path, StringBuffer sb, {bool isStatic: false, String memberName}) {
-  var jsName = _getJsMemberName(declaration);
-  path = (path != null && path.isNotEmpty) ? "${path}.${jsName}" : jsName;
+  if (!declaration.isConstructor) {
+    var jsName = _getJsMemberName(declaration);
+    path = (path != null && path.isNotEmpty) ? "${path}.${jsName}" : jsName;
+  }
   var name = memberName != null ? memberName : _getDeclarationName(declaration);
   if (declaration.isConstructor) {
     sb.write("factory");
@@ -362,8 +377,13 @@ void addMemberHelper(mirrors.MethodMirror declaration, String path, StringBuffer
 }
 
 // TODO(jacobr): make this check more robust.
-bool _isExternal(mirrors.MethodMirror mirror) =>
-    mirror.source != null && mirror.source.startsWith("external ");
+bool _isExternal(mirrors.Mirror mirror) {
+  /*
+  var source = mirror.source;
+  return source != null && source.startsWith("external ");
+  */
+  return mirror.isExternal;
+}
 
 List<String> _generateExternalMethods() {
   var staticCodegen = <String>[];
@@ -372,21 +392,119 @@ List<String> _generateExternalMethods() {
     String jsLibraryName = _getJsName(library);
     library.declarations.forEach((name, declaration) {
       if (declaration is mirrors.MethodMirror) {
-        if (_isExternal(declaration) && (_hasJsName(declaration) || jsLibraryName != null)) {
+        if ((_hasJsName(declaration) || jsLibraryName != null) && _isExternal(declaration)) {
           addMemberHelper(declaration, jsLibraryName, sb);
         }
       } else if (declaration is mirrors.ClassMirror) {
         mirrors.ClassMirror clazz = declaration;
         if (_hasJsName(clazz)) {
           // TODO(jacobr): verify class implements JavaScriptObject.
-          assert(clazz.hasReflectedType);
-          jsInterfaceTypes.add(clazz.reflectedType);
           String jsClassName = _getJsMemberName(clazz);
           var className = mirrors.MirrorSystem.getName(clazz.simpleName);
           var sbPatch = new StringBuffer();
+          jsInterfaceTypes.add(clazz);
           clazz.declarations.forEach((name, declaration) {
             if (declaration is! mirrors.MethodMirror || !_isExternal(declaration)) return;
-            if (declaration.isFactoryConstructor) {
+            if (declaration.isFactoryConstructor && _isAnonymousClass(clazz)) {
+              sbPatch.write("  factory ${className}({");
+              int i = 0;
+              var args = <String>[];
+              for (var p in declaration.parameters) {
+                args.add(mirrors.MirrorSystem.getName(p.simpleName));
+                i++;
+              }
+              sbPatch
+                ..write(args.map((name) => '$name:${_UNDEFINED_VAR}').join(", "))
+                ..write("}) {\n"
+                        "    var ret = new ${_JS_LIBRARY_PREFIX}.JsObject.jsify({});\n");
+              i = 0;
+              for (var p in declaration.parameters) {
+                assert(p.isNamed); // XXX throw
+                var name = args[i];
+                var jsName = mirrors.MirrorSystem.getName(p.simpleName);
+                // XXX apply name conversion rules.
+                sbPatch.write("    if($name != ${_UNDEFINED_VAR}) ret['$jsName'] = $name;\n");
+                i++;
+              }
+
+              sbPatch.write("    return ret;\n"
+                            "  }\n");
+            } else if (declaration.isConstructor || declaration.isFactoryConstructor) {
+              sbPatch.write("  ");
+              addMemberHelper(declaration,
+                  (jsLibraryName != null && jsLibraryName.isNotEmpty) ? "${jsLibraryName}.${jsClassName}" : jsClassName,
+                  sbPatch,
+                  isStatic: true,
+                  memberName: className);
+            }
+          });
+
+          clazz.staticMembers.forEach((memberName, member) {
+            if (_isExternal(member)) {
+              sbPatch.write("  ");
+              addMemberHelper(member,
+                  (jsLibraryName != null && jsLibraryName.isNotEmpty) ? "${jsLibraryName}.${jsClassName}" : jsClassName,
+                  sbPatch,
+                  isStatic: true);
+            }
+          });
+          var typeVariablesClause = '';          
+          if (!clazz.typeVariables.isEmpty) {
+            typeVariablesClause = '<${clazz.typeVariables.map((m) => mirrors.MirrorSystem.getName(m.simpleName)).join(',')}>';
+          }
+          if (sbPatch.isNotEmpty) {
+            sb.write("""
+patch class $className$typeVariablesClause {
+$sbPatch
+}
+""");
+          }
+        }
+      }
+    });
+    if (sb.isNotEmpty) {
+      staticCodegen
+        ..add(uri.toString())
+        ..add("${uri}_js_interop_patch.dart")
+        ..add("""
+import 'dart:js' as ${_JS_LIBRARY_PREFIX};
+
+/**
+ * Placeholder object for cases where we need to determine exactly how many
+ * args were passed to a function.
+ */
+const ${_UNDEFINED_VAR} = const Object();
+
+${sb}
+""");
+    }
+  });
+
+  return staticCodegen;
+}
+
+List<String> _generateExternalMethods2() {
+  var staticCodegen = <String>[];
+  mirrors.currentMirrorSystem().libraries.forEach((uri, library) {
+    var sb = new StringBuffer();
+    String jsLibraryName = _getJsName(library);
+    library.declarations.forEach((name, declaration) {
+      var isExternal = _isExternal(declaration); 
+      if (declaration is mirrors.MethodMirror) {
+        if (isExternal && (_hasJsName(declaration) || jsLibraryName != null)) {
+          addMemberHelper(declaration, jsLibraryName, sb);
+        }
+      } else if (declaration is mirrors.ClassMirror) {
+        mirrors.ClassMirror clazz = declaration;
+        if (_hasJsName(clazz)) {
+          // TODO(jacobr): verify class implements JavaScriptObject.
+          String jsClassName = _getJsMemberName(clazz);
+          var className = mirrors.MirrorSystem.getName(clazz.simpleName);
+          var sbPatch = new StringBuffer();
+          jsInterfaceTypes.add(clazz);
+          clazz.declarations.forEach((name, declaration) {
+            if (declaration is! mirrors.MethodMirror || !declaration.isAbstract || !isExternal) return;
+            if (_hasLiteralAnnotation(declaration) && declaration.isFactoryConstructor) {
               sbPatch.write("  factory ${className}({");
               int i = 0;
               var args = <String>[];
@@ -411,10 +529,10 @@ List<String> _generateExternalMethods() {
 
               sbPatch.write("    return ret;\n"
                             "  }\n");
-            } else if (declaration.isConstructor) {
+            } else if (declaration.isConstructor || declaration.isFactoryConstructor) {
               sbPatch.write("  ");
               addMemberHelper(declaration,
-                  (jsLibraryName != null && jsLibraryName.isNotEmpty) ? "${jsLibraryName}" : "",
+                  (jsLibraryName != null && jsLibraryName.isNotEmpty) ? "${jsLibraryName}.${jsClassName}" : jsClassName,
                   sbPatch,
                   isStatic: true,
                   memberName: className);
@@ -430,9 +548,13 @@ List<String> _generateExternalMethods() {
                   isStatic: true);
             }
           });
+          var typeVariablesClause = '';          
+          if (!clazz.typeVariables.isEmpty) {
+            typeVariablesClause = '<${clazz.typeVariables.map((m) => mirrors.MirrorSystem.getName(m.simpleName)).join(',')}>';
+          }
           if (sbPatch.isNotEmpty) {
             sb.write("""
-patch class $className {
+patch class $className$typeVariablesClause {
 $sbPatch
 }
 """);
@@ -476,8 +598,7 @@ List<String> _generateInteropPatchFiles() {
   var implementsArray = <String>[];
   var listMirror = mirrors.reflectType(List);
 
-  for (var type in jsInterfaceTypes) {
-    mirrors.ClassMirror typeMirror = mirrors.reflectType(type);
+  for (var typeMirror in jsInterfaceTypes) {
     mirrors.LibraryMirror libraryMirror = typeMirror.owner;
     var prefixName;
     if (libraryPrefixes.containsKey(libraryMirror)) {
@@ -737,7 +858,7 @@ void setDartHtmlWrapperFor(JsObject object, wrapper) {
  */
 @Deprecated("Internal Use Only")
 unwrap_jso(dartClass_instance) {
-  if (dartClass_instance is html.DartHtmlDomObject)
+  if (dartClass_instance is html.DartHtmlDomObject && dartClass_instance is! JsObject)

[Alan Knight, 2015/10/30 00:38:58]

There's a way it can be both?

[Jacob, 2015/10/30 00:41:24]

yep... and not just by accident.

@JS
class MyPolymerEvent implements html.MessageEvent {
  external get someFancyProperty;
}

     return dartClass_instance.blink_jsObject;
   else
     return dartClass_instance;
@@ -764,7 +885,7 @@ class JsObject extends NativeFieldWrapperClass2 {
    */
   factory JsObject(JsFunction constructor, [List arguments]) {
     try {
-      return _create(constructor, arguments);
+      return html_common.unwrap_jso(_create(constructor, arguments));
     } catch (e) {
       // Re-throw any errors (returned as a string) as a DomException.
       throw new html.DomException.jsInterop(e);