Some de-duplication.

bridge.go

@@ -193,31 +193,9 @@ func hookGoValueDestroyed(enginep unsafe.Pointer, foldp unsafe.Pointer) {
 
 //export hookGoValueReadField
 func hookGoValueReadField(enginep unsafe.Pointer, foldp unsafe.Pointer, memberIndex C.int, result *C.DataValue) {
+	field := foldField(enginep, foldp, memberIndex)
 	fold := (*valueFold)(foldp)
 
-	if fold.engine == nil {
-		if enginep == nilPtr {
-			panic("reading field from value without an engine pointer; who created the value?")
-		}
-		engine := engines[enginep]
-		if engine == nil {
-			panic("unknown engine pointer; who created the engine?")
-		}
-		fold.engine = engine
-		engine.values[fold.gvalue] = fold
-		before := len(enginePending)
-		delete(enginePending, fold)
-		if len(enginePending) == before {
-			panic("value had no engine, but is not in the pending engine set; who created the value?")
-		}
-	}
-
-	v := reflect.ValueOf(fold.gvalue)
-	for v.Type().Kind() == reflect.Ptr {
-		v = v.Elem()
-	}
-	field := v.Field(int(memberIndex))
-
 	// TODO Strings are being passed in an unsafe manner here. There is a
 	// small chance that the field is changed and the garbage collector is run
 	// before C++ has a chance to look at the data. We can solve this problem
@@ -228,11 +206,24 @@ func hookGoValueReadField(enginep unsafe.Pointer, foldp unsafe.Pointer, memberIn
 
 //export hookGoValueWriteField
 func hookGoValueWriteField(enginep unsafe.Pointer, foldp unsafe.Pointer, memberIndex C.int, dvalue *C.DataValue) {
+	field := foldField(enginep, foldp, memberIndex)
+	value := unpackDataValue(dvalue)
+
+	// TODO What to do if it fails?
+	convertAndSet(field, reflect.ValueOf(value))
+}
+
+func convertAndSet(to, from reflect.Value) {
+	// TODO Catch the panic and error out.
+	to.Set(from.Convert(to.Type()))
+}
+
+func foldField(enginep unsafe.Pointer, foldp unsafe.Pointer, memberIndex C.int) reflect.Value {
 	fold := (*valueFold)(foldp)
 
 	if fold.engine == nil {
 		if enginep == nilPtr {
-			panic("reading field from value without an engine pointer; who created the value?")
+			panic("accessing field from value without an engine pointer; who created the value?")
 		}
 		engine := engines[enginep]
 		if engine == nil {
@@ -251,17 +242,6 @@ func hookGoValueWriteField(enginep unsafe.Pointer, foldp unsafe.Pointer, memberI
 	for v.Type().Kind() == reflect.Ptr {
 		v = v.Elem()
 	}
-	field := v.Field(int(memberIndex))
-
-	// TODO Put the above in a function and share with Read.
-
-	value := unpackDataValue(dvalue)
-
-	// TODO What to do if it fails?
-	convertAndSet(field, reflect.ValueOf(value))
+	return v.Field(int(memberIndex))
 }
 
-func convertAndSet(to, from reflect.Value) {
-	// TODO Catch the panic and error out.
-	to.Set(from.Convert(to.Type()))
-}

qml.go

@@ -364,35 +364,14 @@ type TypeSpec struct {
 var types []*TypeSpec
 
 func RegisterType(spec *TypeSpec) error {
-	// Copy and hold a reference to the spec data.
-	localSpec := *spec
-
-	// TODO Validate localSpec fields.
-
-	var err error
-	gui(func() {
-		sample := spec.New()
-		if sample == nil {
-			err = fmt.Errorf("TypeSpec.New for type %q returned nil", spec.Name)
-			return
-		}
-
-		cloc := C.CString(localSpec.Location)
-		cname := C.CString(localSpec.Name)
-		C.registerType(cloc, C.int(localSpec.Major), C.int(localSpec.Minor), cname, typeInfo(sample), unsafe.Pointer(&localSpec))
-		// TODO Check if qmlRegisterType keeps a reference to those.
-		//C.free(unsafe.Pointer(cloc))
-		//C.free(unsafe.Pointer(cname))
-		types = append(types, &localSpec)
-	})
-
-	// TODO Are there really no errors possible from qmlRegisterType?
-	return err
+	return registerType(spec, false)
 }
 
-// TODO Put logic in RegisterType and RegisterSingle in a single internal function.
-
 func RegisterSingleton(spec *TypeSpec) error {
+	return registerType(spec, true)
+}
+
+func registerType(spec *TypeSpec, singleton bool) error {
 	// Copy and hold a reference to the spec data.
 	localSpec := *spec
 
@@ -408,7 +387,11 @@ func RegisterSingleton(spec *TypeSpec) error {
 
 		cloc := C.CString(localSpec.Location)
 		cname := C.CString(localSpec.Name)
-		C.registerSingleton(cloc, C.int(localSpec.Major), C.int(localSpec.Minor), cname, typeInfo(sample), unsafe.Pointer(&localSpec))
+		if singleton {
+			C.registerSingleton(cloc, C.int(localSpec.Major), C.int(localSpec.Minor), cname, typeInfo(sample), unsafe.Pointer(&localSpec))
+		} else {
+			C.registerType(cloc, C.int(localSpec.Major), C.int(localSpec.Minor), cname, typeInfo(sample), unsafe.Pointer(&localSpec))
+		}
 		// TODO Check if qmlRegisterType keeps a reference to those.
 		//C.free(unsafe.Pointer(cloc))
 		//C.free(unsafe.Pointer(cname))