From 5c603bd0fd53e7dbd709883f289d1e580c86e33d Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Date: Thu, 7 Sep 2017 00:10:10 +0300
Subject: [PATCH] py/objlist: Properly implement comparison with incompatible
 types.

Should raise TypeError, unless it's (in)equality comparison.
---
 py/objlist.c                 | 26 ++++++++++++--------------
 tests/basics/list_compare.py | 10 ++++++++++
 2 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/py/objlist.c b/py/objlist.c
index 6ac33e80e6..d70867dedc 100644
--- a/py/objlist.c
+++ b/py/objlist.c
@@ -87,18 +87,6 @@ STATIC mp_obj_t list_make_new(const mp_obj_type_t *type_in, size_t n_args, size_
     }
 }
 
-// Don't pass MP_BINARY_OP_NOT_EQUAL here
-STATIC bool list_cmp_helper(mp_uint_t op, mp_obj_t self_in, mp_obj_t another_in) {
-    mp_check_self(MP_OBJ_IS_TYPE(self_in, &mp_type_list));
-    if (!MP_OBJ_IS_TYPE(another_in, &mp_type_list)) {
-        return false;
-    }
-    mp_obj_list_t *self = MP_OBJ_TO_PTR(self_in);
-    mp_obj_list_t *another = MP_OBJ_TO_PTR(another_in);
-
-    return mp_seq_cmp_objs(op, self->items, self->len, another->items, another->len);
-}
-
 STATIC mp_obj_t list_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     mp_obj_list_t *self = MP_OBJ_TO_PTR(self_in);
     switch (op) {
@@ -146,8 +134,18 @@ STATIC mp_obj_t list_binary_op(mp_binary_op_t op, mp_obj_t lhs, mp_obj_t rhs) {
         case MP_BINARY_OP_LESS:
         case MP_BINARY_OP_LESS_EQUAL:
         case MP_BINARY_OP_MORE:
-        case MP_BINARY_OP_MORE_EQUAL:
-            return mp_obj_new_bool(list_cmp_helper(op, lhs, rhs));
+        case MP_BINARY_OP_MORE_EQUAL: {
+            if (!MP_OBJ_IS_TYPE(rhs, &mp_type_list)) {
+                if (op == MP_BINARY_OP_EQUAL) {
+                    return mp_const_false;
+                }
+                return MP_OBJ_NULL; // op not supported
+            }
+
+            mp_obj_list_t *another = MP_OBJ_TO_PTR(rhs);
+            bool res = mp_seq_cmp_objs(op, o->items, o->len, another->items, another->len);
+            return mp_obj_new_bool(res);
+        }
 
         default:
             return MP_OBJ_NULL; // op not supported
diff --git a/tests/basics/list_compare.py b/tests/basics/list_compare.py
index eea8814247..fd656c7f15 100644
--- a/tests/basics/list_compare.py
+++ b/tests/basics/list_compare.py
@@ -48,3 +48,13 @@ print([1] <= [1, 0])
 print([1] <= [1, -1])
 print([1, 0] <= [1])
 print([1, -1] <= [1])
+
+
+print([] == {})
+print([] != {})
+print([1] == (1,))
+
+try:
+    print([] < {})
+except TypeError:
+    print("TypeError")