feat(vm/slot): implement Py_TPFLAGS_MANAGED_DICT for class objects (#5949)

Lib/test/test_array.py

@@ -1285,8 +1285,6 @@ class NumberTest(BaseTest):
         self.assertRaises(OverflowError, array.array, self.typecode, [upper+1])
         self.assertRaises(OverflowError, a.__setitem__, 0, upper+1)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_subclassing(self):
         typecode = self.typecode
         class ExaggeratingArray(array.array):

Lib/test/test_importlib/test_metadata_api.py

@@ -139,8 +139,6 @@ class APITests(
     def test_entry_points_missing_group(self):
         assert entry_points(group='missing') == ()
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_entry_points_allows_no_attributes(self):
         ep = entry_points().select(group='entries', name='main')
         with self.assertRaises(AttributeError):

Lib/test/test_property.py

@@ -242,8 +242,6 @@ class PropertySubSlots(property):
 
 class PropertySubclassTests(unittest.TestCase):
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_slots_docstring_copy_exception(self):
         try:
             class Foo(object):

Lib/test/test_weakref.py

@@ -1132,8 +1132,6 @@ class SubclassableWeakrefTestCase(TestBase):
         self.assertIn(r1, refs)
         self.assertIn(r2, refs)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_subclass_refs_with_slots(self):
         class MyRef(weakref.ref):
             __slots__ = "slot1", "slot2"

vm/src/builtins/type.rs

@@ -1038,9 +1038,6 @@ impl Constructor for PyType {
             });
         }
 
-        // TODO: Flags is currently initialized with HAS_DICT. Should be
-        // updated when __slots__ are supported (toggling the flag off if
-        // a class has __slots__ defined).
         let heaptype_slots: Option<PyRef<PyTuple<PyStrRef>>> =
             if let Some(x) = attributes.get(identifier!(vm, __slots__)) {
                 let slots = if x.class().is(vm.ctx.types.str_type) {
@@ -1072,7 +1069,12 @@ impl Constructor for PyType {
         let heaptype_member_count = heaptype_slots.as_ref().map(|x| x.len()).unwrap_or(0);
         let member_count: usize = base_member_count + heaptype_member_count;
 
-        let flags = PyTypeFlags::heap_type_flags() | PyTypeFlags::HAS_DICT;
+        let mut flags = PyTypeFlags::heap_type_flags();
+        // Only add HAS_DICT and MANAGED_DICT if __slots__ is not defined.
+        if heaptype_slots.is_none() {
+            flags |= PyTypeFlags::HAS_DICT | PyTypeFlags::MANAGED_DICT;
+        }
+
         let (slots, heaptype_ext) = {
             let slots = PyTypeSlots {
                 flags,

vm/src/types/slot.rs

@@ -122,6 +122,7 @@ bitflags! {
     #[derive(Copy, Clone, Debug, PartialEq)]
     #[non_exhaustive]
     pub struct PyTypeFlags: u64 {
+        const MANAGED_DICT = 1 << 4;
         const IMMUTABLETYPE = 1 << 8;
         const HEAPTYPE = 1 << 9;
         const BASETYPE = 1 << 10;