comments and simplifications

Author: lukesandberg

turbopack/crates/turbo-tasks-build/src/lib.rs

@@ -154,6 +154,7 @@ pub fn generate_register() {
                 entry.global_name,
             )
             .unwrap();
+            // Register all the trait items for each impl so we can dispatch to them as turbotasks
             for trait_ident in &entry.trait_idents {
                 writeln!(
                     values_code,
@@ -164,6 +165,8 @@ pub fn generate_register() {
                 .unwrap();
             }
             writeln!(values_code, "}}, #[allow(unused_variables)] |value_id| {{").unwrap();
+            // Register all the vtables for the impls so we can dispatch to them as normal indirect
+            // trait calls.
             for trait_ident in &entry.trait_idents {
                 writeln!(
                     values_code,

turbopack/crates/turbo-tasks/src/macro_helpers.rs

@@ -91,8 +91,8 @@ impl<T: ?Sized> VTableRegistry<T> {
         debug_assert!(prev.is_none(), "{id} was already registered");
     }
 
-    pub(crate) fn get(&self, id: &ValueTypeId) -> Option<DynMetadata<T>> {
-        self.map.get(id).map(|r| *r.value())
+    pub(crate) fn get(&self, id: ValueTypeId) -> DynMetadata<T> {
+        *self.map.get(&id).unwrap().value()
     }
 }
 

turbopack/crates/turbo-tasks/src/trait_ref.rs

@@ -97,11 +97,10 @@ where
     type Target = U;
 
     fn deref(&self) -> &Self::Target {
-        // This lookup will fail if the valuye type stored does not actually implement the trait,
+        // This lookup will fail if the value type stored does not actually implement the trait,
         // which implies a bug in either the registry code or the macro code.
-        let metadata = <Box<U> as VcValueTrait>::get_impl_vtables()
-            .get(&self.shared_reference.type_id)
-            .unwrap();
+        let metadata =
+            <Box<U> as VcValueTrait>::get_impl_vtables().get(self.shared_reference.type_id);
         let downcast_ptr = std::ptr::from_raw_parts(
             self.shared_reference.reference.0.as_ptr() as *const (),
             metadata,