Reimplement PySequence_Contains() and instance_contains(), so they work

safely together and don't duplicate logic (the common logic was factored
out into new private API function _PySequence_IterContains()).
Visible change:
    some_complex_number  in  some_instance
no longer blows up if some_instance has __getitem__ but neither
__contains__ nor __iter__.  test_iter changed to ensure that remains true.

1 files changed, 11 insertions, 1 deletions

diff --git a/Include/abstract.h b/Include/abstract.h
index d5f4a9978d..9082edb0b8 100644
--- a/Include/abstract.h
+++ b/Include/abstract.h
@@ -932,7 +932,17 @@ xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx*/
 	 expression: o.count(value).
        */
 
-     DL_IMPORT(int) PySequence_Contains(PyObject *o, PyObject *value);
+     DL_IMPORT(int) PySequence_Contains(PyObject *seq, PyObject *ob);
+       /*
+         Return -1 if error; 1 if ob in seq; 0 if ob not in seq.
+         Use __contains__ if possible, else _PySequence_IterContains().
+       */
+
+     DL_IMPORT(int) _PySequence_IterContains(PyObject *seq, PyObject *ob);
+       /*
+         Return -1 if error; 1 if ob in seq; 0 if ob not in seq.
+         Always uses the iteration protocol, and only Py_EQ comparisons.
+       */
 
 /* For DLL-level backwards compatibility */
 #undef PySequence_In