test: move __class__ layout check to builtin_type snippet

Copilot · youknowone · Copilot · commit 22490e340219 · 2025-12-25T12:39:37.000Z
Co-authored-by: youknowone &lt;69878+youknowone@users.noreply.github.com&gt;
diff --git a/crates/vm/src/vm/interpreter.rs b/crates/vm/src/vm/interpreter.rs
@@ -169,31 +169,4 @@ mod tests {
             assert_eq!(value.as_str(), "Hello Hello Hello Hello ")
         })
     }
-
-    #[test]
-    fn class_assignment_layout_mismatch_error() {
-        Interpreter::without_stdlib(Default::default()).enter(|vm| {
-            let scope = vm.new_scope_with_builtins();
-            let source = r#"
-class TypeA:
-    def __init__(self):
-        self.a = 1
-
-class TypeB:
-    __slots__ = "b"
-    def __init__(self):
-        self.b = 2
-
-obj = TypeA()
-try:
-    obj.__class__ = TypeB
-except TypeError as e:
-    assert str(e) == "__class__ assignment: 'TypeB' object layout differs from 'TypeA'"
-else:
-    raise AssertionError("TypeError not raised")
-"#;
-            vm.run_code_string(scope, source, "<test>".to_owned())
-                .expect("script should complete without uncaught exceptions");
-        })
-    }
 }
diff --git a/extra_tests/snippets/builtin_type.py b/extra_tests/snippets/builtin_type.py
@@ -240,6 +240,26 @@ class C(B, BB):
 assert C.mro() == [C, B, A, BB, AA, object]
 
 
+class TypeA:
+    def __init__(self):
+        self.a = 1
+
+
+class TypeB:
+    __slots__ = "b"
+
+    def __init__(self):
+        self.b = 2
+
+
+obj = TypeA()
+with assert_raises(TypeError) as cm:
+    obj.__class__ = TypeB
+assert "__class__ assignment: 'TypeB' object layout differs from 'TypeA'" in str(
+    cm.exception
+)
+
+
 assert type(Exception.args).__name__ == "getset_descriptor"
 assert type(None).__bool__(None) is False
 
