fix(builtins): should not appear in public value

src/ty/internal/attrset.rs

@@ -42,7 +42,10 @@ impl<'jit: 'vm, 'vm> AttrSet<'jit, 'vm> {
     }
 
     pub fn select(&self, sym: usize) -> Option<Value<'jit, 'vm>> {
-        self.data.get(&sym).cloned()
+        self.data.get(&sym).cloned().map(|val| match val {
+            Value::Builtins(x) => Value::AttrSet(x.upgrade().unwrap()),
+            val => val
+        })
     }
 
     pub fn has_attr(&self, sym: usize) -> bool {

src/ty/internal/mod.rs

@@ -379,11 +379,7 @@ impl<'jit, 'vm> Value<'jit, 'vm> {
                 self.typename()
             ))),
         }?;
-        if let Value::Builtins(weak) = val {
-            *self = Value::AttrSet(weak.upgrade().unwrap())
-        } else {
-            *self = val;
-        }
+        *self = val;
         Ok(self)
     }
 
@@ -398,11 +394,7 @@ impl<'jit, 'vm> Value<'jit, 'vm> {
                 )));
             }
         };
-        if let Value::Builtins(weak) = val {
-            *self = Value::AttrSet(weak.upgrade().unwrap())
-        } else {
-            *self = val;
-        }
+        *self = val;
         Ok(self)
     }