Two ways binding with optimized public property in the interpreter

sixtyfps_runtime/corelib/items.rs

@@ -746,7 +746,7 @@ pub unsafe extern "C" fn sixtyfps_flickable_data_free(data: *mut FlickableDataBo
 
 /// The implementation of the `PropertyAnimation` element
 #[repr(C)]
-#[derive(FieldOffsets, Default, BuiltinItem, Clone)]
+#[derive(FieldOffsets, Default, BuiltinItem, Clone, Debug)]
 #[pin]
 pub struct PropertyAnimation {
     #[rtti_field]

sixtyfps_runtime/interpreter/dynamic_component.rs

@@ -512,6 +512,9 @@ fn generate_component<'id>(
     }
 
     for (name, decl) in &root_component.root_element.borrow().property_declarations {
+        if decl.is_alias.is_some() {
+            continue;
+        }
         let (prop, type_info) = match decl.property_type {
             Type::Float32 => animated_property_info::<f32>(),
             Type::Int32 => animated_property_info::<i32>(),

sixtyfps_runtime/interpreter/eval.rs

@@ -194,18 +194,20 @@ pub fn eval_expression(
             "naked builtin function reference not allowed, should be handled by function call"
         ),
         Expression::PropertyReference(NamedReference { element, name }) => {
-            load_property(component, &element.upgrade().unwrap(), name.as_ref())
+            load_property(component, &element.upgrade().unwrap(), name.as_ref()).unwrap()
         }
         Expression::RepeaterIndexReference { element } => load_property(
             component,
             &element.upgrade().unwrap().borrow().base_type.as_component().root_element,
             "index",
-        ),
+        )
+        .unwrap(),
         Expression::RepeaterModelReference { element } => load_property(
             component,
             &element.upgrade().unwrap().borrow().base_type.as_component().root_element,
             "model_data",
-        ),
+        )
+        .unwrap(),
         Expression::FunctionParameterReference { index, .. } => {
             local_context.function_arguments[*index].clone()
         }
@@ -275,18 +277,19 @@ pub fn eval_expression(
         }
         Expression::SelfAssignment { lhs, rhs, op } => match &**lhs {
             Expression::PropertyReference(NamedReference { element, name }) => {
-                let mut eval = |lhs| {
-                    let rhs = eval_expression(&**rhs, component, local_context);
-                    match (lhs, rhs, op) {
-                        (_, rhs, '=') => rhs,
-                        (Value::Number(a), Value::Number(b), '+') => Value::Number(a + b),
-                        (Value::Number(a), Value::Number(b), '-') => Value::Number(a - b),
-                        (Value::Number(a), Value::Number(b), '/') => Value::Number(a / b),
-                        (Value::Number(a), Value::Number(b), '*') => Value::Number(a * b),
-                        (lhs, rhs, op) => panic!("unsupported {:?} {} {:?}", lhs, op, rhs),
-                    }
+                let rhs = eval_expression(&**rhs, component, local_context);
+                if *op == '=' {
+                    store_property(component, &element.upgrade().unwrap(), name.as_ref(), rhs)
+                        .unwrap();
+                    return Value::Void;
+                }
+                let eval = |lhs| match (lhs, rhs, op) {
+                    (Value::Number(a), Value::Number(b), '+') => Value::Number(a + b),
+                    (Value::Number(a), Value::Number(b), '-') => Value::Number(a - b),
+                    (Value::Number(a), Value::Number(b), '/') => Value::Number(a / b),
+                    (Value::Number(a), Value::Number(b), '*') => Value::Number(a * b),
+                    (lhs, rhs, op) => panic!("unsupported {:?} {} {:?}", lhs, op, rhs),
                 };
-
                 let element = element.upgrade().unwrap();
                 generativity::make_guard!(guard);
                 let enclosing_component =
@@ -386,16 +389,14 @@ pub fn eval_expression(
     }
 }
 
-fn load_property(component: InstanceRef, element: &ElementRc, name: &str) -> Value {
+pub fn load_property(component: InstanceRef, element: &ElementRc, name: &str) -> Result<Value, ()> {
     generativity::make_guard!(guard);
     let enclosing_component = enclosing_component_for_element(&element, component, guard);
     let element = element.borrow();
     if element.id == element.enclosing_component.upgrade().unwrap().root_element.borrow().id {
         if let Some(x) = enclosing_component.component_type.custom_properties.get(name) {
             return unsafe {
-                x.prop
-                    .get(Pin::new_unchecked(&*enclosing_component.as_ptr().add(x.offset)))
-                    .unwrap()
+                x.prop.get(Pin::new_unchecked(&*enclosing_component.as_ptr().add(x.offset)))
             };
         }
     };
@@ -406,7 +407,37 @@ fn load_property(component: InstanceRef, element: &ElementRc, name: &str) -> Val
         .unwrap_or_else(|| panic!("Unkown element for {}.{}", element.id, name));
     core::mem::drop(element);
     let item = unsafe { item_info.item_from_component(enclosing_component.as_ptr()) };
-    item_info.rtti.properties[name].get(item)
+    Ok(item_info.rtti.properties.get(name).ok_or(())?.get(item))
+}
+
+pub fn store_property(
+    component_instance: InstanceRef,
+    element: &ElementRc,
+    name: &str,
+    value: Value,
+) -> Result<(), ()> {
+    generativity::make_guard!(guard);
+    let enclosing_component = enclosing_component_for_element(&element, component_instance, guard);
+    let maybe_animation = crate::dynamic_component::animation_for_property(
+        enclosing_component,
+        &element.borrow().property_animations,
+        name,
+    );
+
+    let component = element.borrow().enclosing_component.upgrade().unwrap();
+    if element.borrow().id == component.root_element.borrow().id {
+        if let Some(x) = enclosing_component.component_type.custom_properties.get(name) {
+            unsafe {
+                let p = Pin::new_unchecked(&*enclosing_component.as_ptr().add(x.offset));
+                return x.prop.set(p, value, maybe_animation);
+            }
+        }
+    };
+    let item_info = &enclosing_component.component_type.items[element.borrow().id.as_str()];
+    let item = unsafe { item_info.item_from_component(enclosing_component.as_ptr()) };
+    let p = &item_info.rtti.properties.get(name).ok_or(())?;
+    p.set(item, value, maybe_animation);
+    Ok(())
 }
 
 pub fn window_ref(component: InstanceRef) -> Option<sixtyfps_corelib::eventloop::ComponentWindow> {

sixtyfps_runtime/interpreter/lib.rs

@@ -68,19 +68,19 @@ impl<'id> dynamic_component::ComponentDescription<'id> {
         if !core::ptr::eq((&self.ct) as *const _, component.get_vtable() as *const _) {
             return Err(());
         }
-        let x = self.custom_properties.get(name).ok_or(())?;
         generativity::make_guard!(guard);
-        let maybe_animation = dynamic_component::animation_for_property(
-            unsafe { InstanceRef::from_pin_ref(component, guard) },
-            &self.original.root_element.borrow().property_animations,
-            name,
-        );
-        unsafe {
-            x.prop.set(
-                Pin::new_unchecked(&*component.as_ptr().add(x.offset)),
-                value,
-                maybe_animation,
-            )
+        let c = unsafe { InstanceRef::from_pin_ref(component, guard) };
+        if let Some(alias) = self
+            .original
+            .root_element
+            .borrow()
+            .property_declarations
+            .get(name)
+            .and_then(|d| d.is_alias.as_ref())
+        {
+            eval::store_property(c, &alias.element.upgrade().unwrap(), &alias.name, value)
+        } else {
+            eval::store_property(c, &self.original.root_element, name, value)
         }
     }
 
@@ -114,8 +114,21 @@ impl<'id> dynamic_component::ComponentDescription<'id> {
         if !core::ptr::eq((&self.ct) as *const _, component.get_vtable() as *const _) {
             return Err(());
         }
-        let x = self.custom_properties.get(name).ok_or(())?;
-        unsafe { x.prop.get(Pin::new_unchecked(&*component.as_ptr().add(x.offset))) }
+        if let Some(alias) = self
+            .original
+            .root_element
+            .borrow()
+            .property_declarations
+            .get(name)
+            .and_then(|d| d.is_alias.as_ref())
+        {
+            generativity::make_guard!(guard);
+            let c = unsafe { InstanceRef::from_pin_ref(component, guard) };
+            eval::load_property(c, &alias.element.upgrade().unwrap(), &alias.name)
+        } else {
+            let x = self.custom_properties.get(name).ok_or(())?;
+            unsafe { x.prop.get(Pin::new_unchecked(&*component.as_ptr().add(x.offset))) }
+        }
     }
 
     /// Sets an handler for a signal

tests/cases/two_way_simple.60

@@ -76,5 +76,28 @@ assert_eq(instance.get_sub_foo1(), 15);
 assert_eq(instance.get_sub_foo2(), 15);
 ```
 
+```js
+var instance = new sixtyfps.TestCase({});
+assert.equal(instance.sub_width1, 80.);
+assert.equal(instance.sub_width2, 80.);
+instance.sub_width1 = (99.);
+assert.equal(instance.sub_width1, 99.);
+assert.equal(instance.sub_width2, 99.);
+
+// breaks the binding
+instance.sub_width2 = (23.);
+assert.equal(instance.sub_width1, 99.);
+assert.equal(instance.sub_width2, 23.);
+instance.sub_width1 = (88.);
+assert.equal(instance.sub_width1, 88.);
+assert.equal(instance.sub_width2, 23.);
+
+
+assert.equal(instance.sub_foo1, 44);
+assert.equal(instance.sub_foo2, 44);
+instance.sub_foo1 = (15);
+assert.equal(instance.sub_foo1, 15);
+assert.equal(instance.sub_foo2, 15);
+```
 
 */