commit 18b711c5a7f90d88fb74748f18fa8ef49d8486c7
author Serhiy Storchaka <storchaka@gmail.com> Sun Aug 04 14:12:48 2019 +0300
committer GitHub <noreply@github.com> Sun Aug 04 14:12:48 2019 +0300
tree d04ab59ccadbade80f8999c921dd3a19b62a9cc9
parent 17e52649c0e7e9389f1cc2444a53f059e24e6bca

bpo-37648: Fixed minor inconsistency in some __contains__. (GH-14904)

The collection's item is now always at the left and
the needle is on the right of ==.

Objects/abstract.c

diff --git a/Objects/abstract.c b/Objects/abstract.c
index db1c306..f93d73f 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -2016,7 +2016,7 @@
             break;
         }
 
-        cmp = PyObject_RichCompareBool(obj, item, Py_EQ);
+        cmp = PyObject_RichCompareBool(item, obj, Py_EQ);
         Py_DECREF(item);
         if (cmp < 0)
             goto Fail;

Objects/dictobject.c

diff --git a/Objects/dictobject.c b/Objects/dictobject.c
index b6205d9..f168ad5 100644
--- a/Objects/dictobject.c
+++ b/Objects/dictobject.c
@@ -4392,7 +4392,7 @@
         return 0;
     }
     Py_INCREF(found);
-    result = PyObject_RichCompareBool(value, found, Py_EQ);
+    result = PyObject_RichCompareBool(found, value, Py_EQ);
     Py_DECREF(found);
     return result;
 }

Objects/listobject.c

diff --git a/Objects/listobject.c b/Objects/listobject.c
index d012ab9..cea9b24 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -449,8 +449,7 @@
     int cmp;
 
     for (i = 0, cmp = 0 ; cmp == 0 && i < Py_SIZE(a); ++i)
-        cmp = PyObject_RichCompareBool(el, PyList_GET_ITEM(a, i),
-                                           Py_EQ);
+        cmp = PyObject_RichCompareBool(PyList_GET_ITEM(a, i), el, Py_EQ);
     return cmp;
 }
 

Objects/tupleobject.c

diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
index fc2d274..aeaf845 100644
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -403,8 +403,7 @@
     int cmp;
 
     for (i = 0, cmp = 0 ; cmp == 0 && i < Py_SIZE(a); ++i)
-        cmp = PyObject_RichCompareBool(el, PyTuple_GET_ITEM(a, i),
-                                           Py_EQ);
+        cmp = PyObject_RichCompareBool(PyTuple_GET_ITEM(a, i), el, Py_EQ);
     return cmp;
 }