Fix type_get_bases() and type_get_mro().

ericsnowcurrently · ericsnowcurrently · commit 6c29756385d8 · 2023-04-27T15:13:51.000-06:00
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
@@ -865,7 +865,11 @@ set_bases(PyTypeObject *type, PyObject *bases)
 static PyObject *
 type_get_bases(PyTypeObject *type, void *context)
 {
-    return Py_NewRef(get_bases(type));
+    PyObject *bases = get_bases(type);
+    if (bases == NULL) {
+        Py_RETURN_NONE;
+    }
+    return Py_NewRef(bases);
 }
 
 static inline PyObject *
@@ -912,7 +916,11 @@ clear_mro(PyTypeObject *type)
 static PyObject *
 type_get_mro(PyTypeObject *type, void *context)
 {
-    return Py_NewRef(get_mro(type));
+    PyObject *mro = get_mro(type);
+    if (mro == NULL) {
+        Py_RETURN_NONE;
+    }
+    return Py_NewRef(mro);
 }
 
 static PyTypeObject *best_base(PyObject *);

Original file line number	Diff line number	Diff line change
`@@ -865,7 +865,11 @@ set_bases(PyTypeObject type, PyObject bases)`
`865`	`865`	`static PyObject *`
`866`	`866`	`type_get_bases(PyTypeObject type, void context)`
`867`	`867`	`{`
`868`		`- return Py_NewRef(get_bases(type));`
	`868`	`+ PyObject *bases = get_bases(type);`
	`869`	`+ if (bases == NULL) {`
	`870`	`+ Py_RETURN_NONE;`
	`871`	`+ }`
	`872`	`+ return Py_NewRef(bases);`
`869`	`873`	`}`
`870`	`874`
`871`	`875`	`static inline PyObject *`
`@@ -912,7 +916,11 @@ clear_mro(PyTypeObject *type)`
`912`	`916`	`static PyObject *`
`913`	`917`	`type_get_mro(PyTypeObject type, void context)`
`914`	`918`	`{`
`915`		`- return Py_NewRef(get_mro(type));`
	`919`	`+ PyObject *mro = get_mro(type);`
	`920`	`+ if (mro == NULL) {`
	`921`	`+ Py_RETURN_NONE;`
	`922`	`+ }`
	`923`	`+ return Py_NewRef(mro);`
`916`	`924`	`}`
`917`	`925`
`918`	`926`	`static PyTypeObject best_base(PyObject );`