Don't try to put __new__ on every type

vm/src/macros.rs

@@ -152,11 +152,6 @@ macro_rules! extend_class {
         $(
             $crate::extend_class!(@set_attr($ctx, $class, $name, $value));
         )*
-        if $class.slots.borrow().new.is_some() {
-            $class.attributes.borrow_mut().entry("__new__".into()).or_insert_with(|| {
-                $ctx.new_classmethod($crate::obj::objtype::type_new)
-            });
-        }
     };
 
     (@set_attr($ctx:expr, $class:expr, (slot $slot_name:ident), $value:expr)) => {

vm/src/obj/objobject.rs

@@ -158,6 +158,7 @@ pub fn init(context: &PyContext) {
 
     extend_class!(context, object, {
         (slot new) => new_instance,
+        "__new__" => context.new_classmethod(objtype::type_new),
         "__init__" => context.new_rustfunc(object_init),
         "__class__" =>
         PropertyBuilder::new(context)

vm/src/obj/objtype.rs

@@ -294,11 +294,7 @@ fn type_new_slot(metatype: PyClassRef, args: PyFuncArgs, vm: &VirtualMachine) ->
     let mut bases: Vec<PyClassRef> = bases.iter(vm)?.collect::<Result<Vec<_>, _>>()?;
     bases.push(vm.ctx.object());
 
-    let mut attributes = dict.to_attributes();
-
-    attributes
-        .entry("__new__".into())
-        .or_insert_with(|| vm.ctx.new_classmethod(type_new));
+    let attributes = dict.to_attributes();
 
     let mut winner = metatype.clone();
     for base in &bases {

vm/src/stdlib/itertools.rs

@@ -88,23 +88,21 @@ impl PyValue for PyItertoolsCompress {
 
 #[pyimpl]
 impl PyItertoolsCompress {
-    #[pymethod(name = "__new__")]
-    #[allow(clippy::new_ret_no_self)]
+    #[pyslot(new)]
     fn new(
-        _cls: PyClassRef,
+        cls: PyClassRef,
         data: PyObjectRef,
         selector: PyObjectRef,
         vm: &VirtualMachine,
-    ) -> PyResult {
+    ) -> PyResult<PyRef<Self>> {
         let data_iter = get_iter(vm, &data)?;
         let selector_iter = get_iter(vm, &selector)?;
 
-        Ok(PyItertoolsCompress {
+        PyItertoolsCompress {
             data: data_iter,
             selector: selector_iter,
         }
-        .into_ref(vm)
-        .into_object())
+        .into_ref_with_type(vm, cls)
     }
 
     #[pymethod(name = "__next__")]