Make FunctionTypeMirror and ClosureMirror handle user-defined classes that implement the call opera…

runtime/lib/mirrors.cc

Index: runtime/lib/mirrors.cc
diff --git a/runtime/lib/mirrors.cc b/runtime/lib/mirrors.cc
index 874915f014d0e29471272f1eac0dc59dd4f5c090..45c50a6d999054e59663f57f3e6b5979b3b0a5c3 100644
--- a/runtime/lib/mirrors.cc
+++ b/runtime/lib/mirrors.cc
@@ -107,11 +107,18 @@ static RawInstance* CreateTypedefMirror(const Class& cls,
   return CreateMirror(Symbols::_LocalTypedefMirrorImpl(), args);
 }
 
+static RawInstance* CreateFunctionTypeMirror(const Class& cls,
+                                             const Instance& owner_mirror) {
+  const Array& args = Array::Handle(Array::New(2));
+  args.SetAt(0, MirrorReference::Handle(MirrorReference::New(cls)));
+  args.SetAt(1, owner_mirror);
+  return CreateMirror(Symbols::_LocalFunctionTypeMirrorImpl(), args);
+}
 
-static RawInstance* CreateFunctionTypeMirror(const Class& cls) {
+static RawInstance* CreateClosureTypeMirror(const Class& cls) {
   const Array& args = Array::Handle(Array::New(1));
   args.SetAt(0, MirrorReference::Handle(MirrorReference::New(cls)));
-  return CreateMirror(Symbols::_LocalFunctionTypeMirrorImpl(), args);
+  return CreateMirror(Symbols::_LocalClosureTypeMirrorImpl(), args);
 }
 
 
@@ -153,19 +160,41 @@ static RawInstance* CreateVariableMirror(const Field& field,
   return CreateMirror(Symbols::_LocalVariableMirrorImpl(), args);
 }
 
+static RawFunction* CallMethod(const Class& cls) {
+  if (cls.IsSignatureClass()) {
+    return cls.signature_function();
+  }
+
+  Class& lookup_cls = Class::Handle(cls.raw());
+  Function& call_function = Function::Handle();
+  do {
+    call_function = lookup_cls.LookupDynamicFunction(Symbols::Call());
+    if (!call_function.IsNull()) {
+      return call_function.raw();
+    }
+    lookup_cls = lookup_cls.SuperClass();
+  } while (!lookup_cls.IsNull());
+  return Function::null();
+}
 
 static RawInstance* CreateClassMirror(const Class& cls,
                                       const Instance& owner_mirror) {
   if (cls.IsSignatureClass()) {
     if (cls.IsCanonicalSignatureClass()) {
       // We represent function types as canonical signature classes.
-      return CreateFunctionTypeMirror(cls);
+      return CreateClosureTypeMirror(cls);
     } else {
       // We represent typedefs as non-canonical signature classes.
       return CreateTypedefMirror(cls, owner_mirror);
     }
   }
 
+  const Function& call_function = Function::Handle(CallMethod(cls));
+  if (!call_function.IsNull()) {
+    // A user-defined class that implements the call operator.
+    return CreateFunctionTypeMirror(cls, owner_mirror);
+  }
+
   const Array& args = Array::Handle(Array::New(2));
   args.SetAt(0, MirrorReference::Handle(MirrorReference::New(cls)));
   args.SetAt(1, String::Handle(cls.UserVisibleName()));
@@ -323,10 +352,21 @@ DEFINE_NATIVE_ENTRY(DeclarationMirror_metadata, 1) {
 }
 
 
+DEFINE_NATIVE_ENTRY(FunctionTypeMirror_call_method, 2) {
+  GET_NON_NULL_NATIVE_ARGUMENT(Instance,
+                               owner_mirror,
+                               arguments->NativeArgAt(0));
+  GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(1));
+  const Class& cls = Class::Handle(ref.GetClassReferent());
+  const Function& func = Function::Handle(CallMethod(cls));
+  return CreateMethodMirror(func, owner_mirror);
+}
+
+
 DEFINE_NATIVE_ENTRY(FunctionTypeMirror_parameters, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(0));
   const Class& cls = Class::Handle(ref.GetClassReferent());
-  const Function& func = Function::Handle(cls.signature_function());
+  const Function& func = Function::Handle(CallMethod(cls));
   return CreateParameterMirrorList(func);

[siva, 2013/08/06 23:32:07]

Does CreateParameterMirrorList deal with func being null?
CallMethod can potentially return Function::null()

[rmacnak, 2013/08/07 00:10:21]

The class reflected by a FunctionTypeMirror should always have a call method.
Added asserts.

 }
 
@@ -334,7 +374,7 @@ DEFINE_NATIVE_ENTRY(FunctionTypeMirror_parameters, 1) {
 DEFINE_NATIVE_ENTRY(FunctionTypeMirror_return_type, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(0));
   const Class& cls = Class::Handle(ref.GetClassReferent());
-  const Function& func = Function::Handle(cls.signature_function());
+  const Function& func = Function::Handle(CallMethod(cls));
   const AbstractType& return_type = AbstractType::Handle(func.result_type());

[siva, 2013/08/06 23:32:07]

Ditto comment here about CallMethod returning Function::null()

   return CreateTypeMirror(return_type);
 }
@@ -723,10 +763,13 @@ DEFINE_NATIVE_ENTRY(ClosureMirror_apply, 2) {
 
 DEFINE_NATIVE_ENTRY(ClosureMirror_function, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(Instance, closure, arguments->NativeArgAt(0));
-  ASSERT(closure.IsClosure());
+  ASSERT(!closure.IsNull());
+
+  Function& function = Function::Handle();
+  bool callable = closure.IsCallable(&function, NULL);
+  ASSERT(callable);
 
-  const Function& func = Function::Handle(Closure::function(closure));
-  return CreateMethodMirror(func, Instance::null_instance());
+  return CreateMethodMirror(function, Instance::null_instance());
 }