From 69d081a7cf7e0ae1e815365af8b3c19be293da84 Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Date: Sun, 25 May 2014 02:29:40 +0300
Subject: [PATCH] py: Handle case of slice start > stop in common sequence
 function.

---
 py/objstr.c   | 3 ---
 py/sequence.c | 6 ++++++
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/py/objstr.c b/py/objstr.c
index 67de2ce804..4ec1034e1e 100644
--- a/py/objstr.c
+++ b/py/objstr.c
@@ -355,9 +355,6 @@ STATIC mp_obj_t str_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
             if (!mp_seq_get_fast_slice_indexes(self_len, index, &start, &stop)) {
                 assert(0);
             }
-            if (start >= stop) {
-                return MP_OBJ_NEW_QSTR(MP_QSTR_);
-            }
             return str_new(type, self_data + start, stop - start);
         }
 #endif
diff --git a/py/sequence.c b/py/sequence.c
index 2c1f6a836c..0a4bb26b31 100644
--- a/py/sequence.c
+++ b/py/sequence.c
@@ -88,6 +88,12 @@ bool mp_seq_get_fast_slice_indexes(machine_uint_t len, mp_obj_t slice, machine_u
     } else if (stop > len) {
         stop = len;
     }
+
+    // CPython returns empty sequence in such case, or point for assignment is at start
+    if (start > stop) {
+        stop = start;
+    }
+
     *begin = start;
     *end = stop;
     return true;