Enable TestMethodsMutating

kralka · kralka · commit 344081189a43 · 2025-10-25T12:32:04.000+02:00
Make Dict::lookup check if the dictionary has been modified. This is a
workaround for a possible segfault. See bpo-46615 for the original
discussion in CPython.
diff --git a/Lib/test/test_set.py b/Lib/test/test_set.py
@@ -1898,7 +1898,6 @@ class TestBinaryOpsMutating_Subclass_Set(TestBinaryOpsMutating, unittest.TestCas
     constructor2 = set
 
 
-@unittest.skip("TODO: RUSTPYTHON; segfault")
 class TestMethodsMutating(TestOperationsMutating):
 
     def test_issubset_with_mutation(self):
diff --git a/vm/src/dict_inner.rs b/vm/src/dict_inner.rs
@@ -582,10 +582,12 @@ impl<T: Clone> Dict<T> {
                 });
                 loop {
                     let index_index = idxs.next();
-                    let index_entry = *unsafe {
-                        // Safety: index_index is generated
-                        inner.indices.get_unchecked(index_index)
-                    };
+                    let index_entry_ptr = inner.indices.get(index_index);
+                    if index_entry_ptr.is_none() {
+                        // Dictionary was modified under our hands, see TestMethodsMutating.
+                        continue 'outer;
+                    }
+                    let index_entry = *index_entry_ptr.unwrap();
                     match index_entry {
                         IndexEntry::DUMMY => {
                             if free_slot.is_none() {
