[Python-checkins] bpo-39453: Add testcase for bpo-39453 (GH-18202)

[Miss Islington (bot)]

https://github.com/python/cpython/commit/9e1ed518a576897f914227bf538bac426a02a081
commit: 9e1ed518a576897f914227bf538bac426a02a081
branch: master
author: Dong-hee Na <donghee.na92 at gmail.com>
committer: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
date: 2020-01-27T09:04:25-08:00
summary:

bpo-39453: Add testcase for bpo-39453 (GH-18202)



https://bugs.python.org/issue39453



Automerge-Triggered-By: @pablogsal

Automerge-Triggered-By: @pablogsal

files:
M Lib/test/test_list.py
M Objects/listobject.c

diff --git a/Lib/test/test_list.py b/Lib/test/test_list.py
index 33a55f76d9b2c..3c8d82958fd7c 100644
--- a/Lib/test/test_list.py
+++ b/Lib/test/test_list.py
@@ -225,6 +225,8 @@ def __eq__(self, other):
         # to list elements while calling PyObject_RichCompareBool().
         lst = [X(), X()]
         3 in lst
+        lst = [X(), X()]
+        X() in lst
 
 
 if __name__ == "__main__":
diff --git a/Objects/listobject.c b/Objects/listobject.c
index 38055d5f5f341..2c07ceb0d412c 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -452,7 +452,7 @@ list_contains(PyListObject *a, PyObject *el)
     for (i = 0, cmp = 0 ; cmp == 0 && i < Py_SIZE(a); ++i) {
         item = PyList_GET_ITEM(a, i);
         Py_INCREF(item);
-        cmp = PyObject_RichCompareBool(PyList_GET_ITEM(a, i), el, Py_EQ);
+        cmp = PyObject_RichCompareBool(item, el, Py_EQ);
         Py_DECREF(item);
     }
     return cmp;