Make singleton builtin types immutable (#7423)

moreal · web-flow · commit ed032d31fb24 · 2026-03-14T09:45:43.000+09:00
diff --git a/Lib/test/test_builtin.py b/Lib/test/test_builtin.py
@@ -2434,7 +2434,6 @@ def test_bool_notimplemented(self):
         with self.assertRaisesRegex(TypeError, msg):
             not NotImplemented
 
-    @unittest.expectedFailure # TODO: RUSTPYTHON; AssertionError: TypeError not raised
     def test_singleton_attribute_access(self):
         for singleton in (NotImplemented, Ellipsis):
             with self.subTest(singleton):
diff --git a/crates/vm/src/builtins/singletons.rs b/crates/vm/src/builtins/singletons.rs
@@ -98,7 +98,7 @@ impl Constructor for PyNotImplemented {
     }
 }
 
-#[pyclass(with(Constructor, AsNumber, Representable))]
+#[pyclass(with(Constructor, AsNumber, Representable), flags(IMMUTABLETYPE))]
 impl PyNotImplemented {
     #[pymethod]
     fn __reduce__(&self, vm: &VirtualMachine) -> PyStrRef {
diff --git a/crates/vm/src/builtins/slice.rs b/crates/vm/src/builtins/slice.rs
@@ -393,7 +393,7 @@ impl Constructor for PyEllipsis {
     }
 }
 
-#[pyclass(with(Constructor, Representable))]
+#[pyclass(with(Constructor, Representable), flags(IMMUTABLETYPE))]
 impl PyEllipsis {
     #[pymethod]
     fn __reduce__(&self, vm: &VirtualMachine) -> PyStrRef {

Original file line number	Diff line number	Diff line change
`@@ -98,7 +98,7 @@ impl Constructor for PyNotImplemented {`
`98`	`98`	`}`
`99`	`99`	`}`
`100`	`100`
`101`		`-#[pyclass(with(Constructor, AsNumber, Representable))]`
	`101`	`+#[pyclass(with(Constructor, AsNumber, Representable), flags(IMMUTABLETYPE))]`
`102`	`102`	`impl PyNotImplemented {`
`103`	`103`	`#[pymethod]`
`104`	`104`	`fn __reduce__(&self, vm: &VirtualMachine) -> PyStrRef {`
Original file line number	Diff line number	Diff line change
`@@ -393,7 +393,7 @@ impl Constructor for PyEllipsis {`
`393`	`393`	`}`
`394`	`394`	`}`
`395`	`395`
`396`		`-#[pyclass(with(Constructor, Representable))]`
	`396`	`+#[pyclass(with(Constructor, Representable), flags(IMMUTABLETYPE))]`
`397`	`397`	`impl PyEllipsis {`
`398`	`398`	`#[pymethod]`
`399`	`399`	`fn __reduce__(&self, vm: &VirtualMachine) -> PyStrRef {`