gh-130824: Add tests for NULL in PyLong_*AndOverflow functions

Author: ZeroIntensity

Lib/test/test_capi/test_long.py

@@ -211,9 +211,10 @@ def check_long_asintandoverflow(self, func, min_val, max_val):
 
         self.assertEqual(func(min_val - 1), (-1, -1))
         self.assertEqual(func(max_val + 1), (-1, +1))
+        with self.assertRaises(SystemError):
+            func(None)
 
         # CRASHES func(1.0)
-        # CRASHES func(NULL)
 
     def test_long_asint(self):
         # Test PyLong_AsInt()

Modules/_testlimitedcapi/long.c

@@ -625,7 +625,8 @@ pylong_aslongandoverflow(PyObject *module, PyObject *arg)
     int overflow = UNINITIALIZED_INT;
     long value = PyLong_AsLongAndOverflow(arg, &overflow);
     if (value == -1 && PyErr_Occurred()) {
-        assert(overflow == -1);
+        // overflow can be 0 if a seperate exception occurred
+        assert(overflow == -1 || overflow == 0);
         return NULL;
     }
     return Py_BuildValue("li", value, overflow);
@@ -671,7 +672,7 @@ pylong_aslonglongandoverflow(PyObject *module, PyObject *arg)
     int overflow = UNINITIALIZED_INT;
     long long value = PyLong_AsLongLongAndOverflow(arg, &overflow);
     if (value == -1 && PyErr_Occurred()) {
-        assert(overflow == -1);
+        assert(overflow == -1 || overflow == 0);
         return NULL;
     }
     return Py_BuildValue("Li", value, overflow);