diff --git a/Lib/test/test_functools.py b/Lib/test/test_functools.py index 9ea6747188b..75427dfad34 100644 --- a/Lib/test/test_functools.py +++ b/Lib/test/test_functools.py @@ -1189,6 +1189,25 @@ class TestLRU: self.assertEqual(misses, 4) self.assertEqual(currsize, 2) + def test_lru_type_error(self): + # Regression test for issue #28653. + # lru_cache was leaking when one of the arguments + # wasn't cacheable. + + @functools.lru_cache(maxsize=None) + def infinite_cache(o): + pass + + @functools.lru_cache(maxsize=10) + def limited_cache(o): + pass + + with self.assertRaises(TypeError): + infinite_cache([]) + + with self.assertRaises(TypeError): + limited_cache([]) + def test_lru_with_maxsize_none(self): @self.module.lru_cache(maxsize=None) def fib(n): diff --git a/Modules/_functoolsmodule.c b/Modules/_functoolsmodule.c index fa5fad3e754..2269d05da87 100644 --- a/Modules/_functoolsmodule.c +++ b/Modules/_functoolsmodule.c @@ -793,8 +793,10 @@ infinite_lru_cache_wrapper(lru_cache_object *self, PyObject *args, PyObject *kwd if (!key) return NULL; hash = PyObject_Hash(key); - if (hash == -1) + if (hash == -1) { + Py_DECREF(key); return NULL; + } result = _PyDict_GetItem_KnownHash(self->cache, key, hash); if (result) { Py_INCREF(result); @@ -849,8 +851,10 @@ bounded_lru_cache_wrapper(lru_cache_object *self, PyObject *args, PyObject *kwds if (!key) return NULL; hash = PyObject_Hash(key); - if (hash == -1) + if (hash == -1) { + Py_DECREF(key); return NULL; + } link = (lru_list_elem *)_PyDict_GetItem_KnownHash(self->cache, key, hash); if (link) { lru_cache_extricate_link(link);