Accept None as start and stop parameters for list.index() and tuple.index()

Closes #13340.

diff --git a/Lib/test/list_tests.py b/Lib/test/list_tests.py
index b8d6d6bda6782617e1df66288cad0a331dc9a958..9528052e31d3642840f9e84d380da894466ac4c8 100644 (file)
--- a/Lib/test/list_tests.py
+++ b/Lib/test/list_tests.py
@@ -365,6 +365,13 @@ class CommonTest(seq_tests.CommonTest):
         self.assertEqual(u.index(0, 3), 3)
         self.assertEqual(u.index(0, 3, 4), 3)
         self.assertRaises(ValueError, u.index, 2, 0, -10)
+        self.assertEqual(u.index(1, None), 4)
+        self.assertEqual(u.index(1, None, None), 4)
+        self.assertEqual(u.index(1, 0, None), 4)
+        self.assertEqual(u.index(1, None, 6), 4)
+        self.assertRaises(ValueError, u.index, -1, 3)
+        self.assertRaises(ValueError, u.index, -1, 3, None)
+        self.assertRaises(ValueError, u.index, 1, None, 4)
 
         self.assertRaises(TypeError, u.index)
 

diff --git a/Lib/test/seq_tests.py b/Lib/test/seq_tests.py
index f5e4e0ef552d21a5eed5b361ac7e8befc1d919b1..0c8cf903a8664c0bc5be8658fb6dc860934eadf3 100644 (file)
--- a/Lib/test/seq_tests.py
+++ b/Lib/test/seq_tests.py
@@ -363,6 +363,13 @@ class CommonTest(unittest.TestCase):
         self.assertEqual(u.index(0, 3), 3)
         self.assertEqual(u.index(0, 3, 4), 3)
         self.assertRaises(ValueError, u.index, 2, 0, -10)
+        self.assertEqual(u.index(1, None), 4)
+        self.assertEqual(u.index(1, None, None), 4)
+        self.assertEqual(u.index(1, 0, None), 4)
+        self.assertEqual(u.index(1, None, 6), 4)
+        self.assertRaises(ValueError, u.index, -1, 3)
+        self.assertRaises(ValueError, u.index, -1, 3, None)
+        self.assertRaises(ValueError, u.index, 1, None, 4)
 
         self.assertRaises(TypeError, u.index)
 

diff --git a/Misc/NEWS b/Misc/NEWS
index d053a2b090ea0604e6d80e82d48ec14213c22af7..2f7b54e4e5cba22f2187219a0a2f1c4362458c0f 100644 (file)
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -9,6 +9,9 @@ What's New in Python 2.7.3?
 Core and Builtins
 -----------------
 
+- Issue #13340: Accept None as start and stop parameters for
+  list.index() and tuple.index().
+
 - Issue #10519: Avoid unnecessary recursive function calls in
   setobject.c.
 

diff --git a/Objects/listobject.c b/Objects/listobject.c
index f753643bd39a94987be327c791dea4eed6183cae..10d9c009c1c9230d504343aa681ddf6b6fd79548 100644 (file)
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -2277,12 +2277,20 @@ listindex(PyListObject *self, PyObject *args)
 {
     Py_ssize_t i, start=0, stop=Py_SIZE(self);
     PyObject *v, *format_tuple, *err_string;
+    PyObject *start_obj = NULL, *stop_obj = NULL;
     static PyObject *err_format = NULL;
 
-    if (!PyArg_ParseTuple(args, "O|O&O&:index", &v,
-                                _PyEval_SliceIndex, &start,
-                                _PyEval_SliceIndex, &stop))
+    if (!PyArg_ParseTuple(args, "O|OO:index", &v, &start_obj, &stop_obj))
         return NULL;
+
+    if (start_obj != Py_None)
+        if (!_PyEval_SliceIndex(start_obj, &start))
+            return NULL;
+
+    if (stop_obj != Py_None)
+        if (!_PyEval_SliceIndex(stop_obj, &stop))
+            return NULL;
+
     if (start < 0) {
         start += Py_SIZE(self);
         if (start < 0)

diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
index 3249cccdb79b541c28a3834b92da209c0761a1d2..1f2ab552aeb9632086033bfa4348a22cb5bed13e 100644 (file)
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -510,12 +510,19 @@ static PyObject *
 tupleindex(PyTupleObject *self, PyObject *args)
 {
     Py_ssize_t i, start=0, stop=Py_SIZE(self);
-    PyObject *v;
+    PyObject *v, *start_obj = NULL, *stop_obj = NULL;
 
-    if (!PyArg_ParseTuple(args, "O|O&O&:index", &v,
-                                _PyEval_SliceIndex, &start,
-                                _PyEval_SliceIndex, &stop))
+    if (!PyArg_ParseTuple(args, "O|OO:index", &v, &start_obj, &stop_obj))
         return NULL;
+
+    if (start_obj != Py_None)
+        if (!_PyEval_SliceIndex(start_obj, &start))
+            return NULL;
+
+    if (stop_obj != Py_None)
+        if (!_PyEval_SliceIndex(stop_obj, &stop))
+            return NULL;
+
     if (start < 0) {
         start += Py_SIZE(self);
         if (start < 0)