generate py3k warnings on __getslice__, __delslice__, and __setslice__

Reviewer: Brett Cannon

diff --git a/Lib/test/test_py3kwarn.py b/Lib/test/test_py3kwarn.py
index 274e14716763c65c0353279aa5ba0e300e5bc35f..1b487fe53ad731b3e5a7766f18dbc82e137eb8e6 100644 (file)
--- a/Lib/test/test_py3kwarn.py
+++ b/Lib/test/test_py3kwarn.py
@@ -175,6 +175,28 @@ class TestPy3KWarnings(unittest.TestCase):
             with catch_warning() as w:
                 self.assertWarning(set(), w, expected)
 
+    def test_slice_methods(self):
+        class Spam(object):
+            def __getslice__(self, i, j): pass
+            def __setslice__(self, i, j, what): pass
+            def __delslice__(self, i, j): pass
+        class Egg:
+            def __getslice__(self, i, h): pass
+            def __setslice__(self, i, j, what): pass
+            def __delslice__(self, i, j): pass
+
+        expected = "in 3.x, __{0}slice__ has been removed; use __{0}item__"
+
+        for obj in (Spam(), Egg()):
+            with catch_warning() as w:
+                self.assertWarning(obj[1:2], w, expected.format('get'))
+                w.reset()
+                del obj[3:4]
+                self.assertWarning(None, w, expected.format('del'))
+                w.reset()
+                obj[4:5] = "eggs"
+                self.assertWarning(None, w, expected.format('set'))
+
     def test_tuple_parameter_unpacking(self):
         expected = "tuple parameter unpacking has been removed in 3.x"
         with catch_warning() as w:

diff --git a/Misc/NEWS b/Misc/NEWS
index 9c07eeea2a7472f0ccd46c28f054400b04b815e8..ff754dfbb0b30c126173822092048fda8de94ef8 100644 (file)
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -26,6 +26,9 @@ Core and Builtins
 - Silenced another compiler warning about a used but not defined
   function 'stringlib_contains_obj'.
 
+- Added warnings on the use of ``__getslice__``, ``__setslice__``, or
+  ``__delslice__``.
+
 Library
 -------
 

diff --git a/Objects/classobject.c b/Objects/classobject.c
index caf6b3e7b0de0a5e82a0f255a5a27d4dfca2e658..7d3d0480b513f23769e60bc784fe5cc92fb56749 100644 (file)
--- a/Objects/classobject.c
+++ b/Objects/classobject.c
@@ -1174,8 +1174,15 @@ instance_slice(PyInstanceObject *inst, Py_ssize_t i, Py_ssize_t j)
                if (func == NULL)
                        return NULL;
                arg = Py_BuildValue("(N)", _PySlice_FromIndices(i, j));
-       } else
+       }
+       else {
+               if (PyErr_WarnPy3k("in 3.x, __getslice__ has been removed; "
+                                  "use __getitem__", 1) < 0) {
+                       Py_DECREF(func);
+                       return NULL;
+               }
                arg = Py_BuildValue("(nn)", i, j);
+       }
 
        if (arg == NULL) {
                Py_DECREF(func);
@@ -1257,8 +1264,15 @@ instance_ass_slice(PyInstanceObject *inst, Py_ssize_t i, Py_ssize_t j, PyObject
 
                        arg = Py_BuildValue("(N)",
                                            _PySlice_FromIndices(i, j));
-               } else
+               }
+               else {
+                       if (PyErr_WarnPy3k("in 3.x, __delslice__ has been "
+                                           "removed; use __delitem__", 1) < 0) {
+                               Py_DECREF(func);
+                               return -1;
+                       }
                        arg = Py_BuildValue("(nn)", i, j);
+               }
        }
        else {
                if (setslicestr == NULL) {
@@ -1284,8 +1298,15 @@ instance_ass_slice(PyInstanceObject *inst, Py_ssize_t i, Py_ssize_t j, PyObject
 
                        arg = Py_BuildValue("(NO)",
                                            _PySlice_FromIndices(i, j), value);
-               } else
+               }
+               else {
+                       if (PyErr_WarnPy3k("in 3.x, __setslice__ has been "
+                                          "removed; use __setitem__", 1) < 0) {
+                               Py_DECREF(func);
+                               return -1;
+                       }
                        arg = Py_BuildValue("(nnO)", i, j, value);
+               }
        }
        if (arg == NULL) {
                Py_DECREF(func);

diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 42974f8fccaf715626fe359e58c61f2c724a5c65..02b50128cb1c387ddaa07fa90601a25f3272e79e 100644 (file)
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -4897,7 +4897,17 @@ slot_sq_item(PyObject *self, Py_ssize_t i)
        return NULL;
 }
 
-SLOT2(slot_sq_slice, "__getslice__", Py_ssize_t, Py_ssize_t, "nn")
+static PyObject*
+slot_sq_slice(PyObject *self, Py_ssize_t i, Py_ssize_t j)
+{
+       static PyObject *getslice_str;
+       
+       if (PyErr_WarnPy3k("in 3.x, __getslice__ has been removed; "
+                           "use __getitem__", 1) < 0)
+               return NULL;
+       return call_method(self, "__getslice__", &getslice_str,
+               "nn", i, j);
+}
 
 static int
 slot_sq_ass_item(PyObject *self, Py_ssize_t index, PyObject *value)
@@ -4922,13 +4932,21 @@ slot_sq_ass_slice(PyObject *self, Py_ssize_t i, Py_ssize_t j, PyObject *value)
 {
        PyObject *res;
        static PyObject *delslice_str, *setslice_str;
-
-       if (value == NULL)
+       
+       if (value == NULL) {
+               if (PyErr_WarnPy3k("in 3.x, __delslice__ has been removed; "
+                                  "use __delitem__", 1) < 0)
+                       return -1;
                res = call_method(self, "__delslice__", &delslice_str,
                                  "(nn)", i, j);
-       else
+       }
+       else {
+               if (PyErr_WarnPy3k("in 3.x, __setslice__ has been removed; "
+                                       "use __setitem__", 1) < 0)
+                       return -1;              
                res = call_method(self, "__setslice__", &setslice_str,
-                                 "(nnO)", i, j, value);
+                         "(nnO)", i, j, value);
+       }
        if (res == NULL)
                return -1;
        Py_DECREF(res);