gh-144584: Remove support for non-int's in __int__/__index__()

Doc/deprecations/pending-removal-in-future.rst

@@ -26,9 +26,6 @@ although there is currently no date scheduled for their removal.
     :keyword:`and`, :keyword:`else`, :keyword:`for`, :keyword:`if`,
     :keyword:`in`, :keyword:`is` and :keyword:`or`.  In a future release it
     will be changed to a syntax error. (:gh:`87999`)
-  * Support for ``__index__()`` and ``__int__()`` method returning non-int type:
-    these methods will be required to return an instance of a strict subclass of
-    :class:`int`.
   * Support for ``__float__()`` method returning a strict subclass of
     :class:`float`: these methods will be required to return an instance of
     :class:`float`.

Doc/whatsnew/3.15.rst

@@ -1303,6 +1303,13 @@ zipimport
   Use :meth:`zipimport.zipimporter.exec_module` instead.
   (Contributed by Jiahao Li in :gh:`133656`.)
 
+Others
+------
+
+* Remove support for returning non-:class:`int` objects in
+  :meth:`~object.__index__` and :meth:`~object.__int__`.
+  (Contributed by Sergey B Kirpichev in :gh:`144584`.)
+
 
 Deprecated
 ==========

Lib/test/test_capi/test_float.py

@@ -116,8 +116,7 @@ def __float__(self):
         self.assertRaises(TypeError, asdouble, BadIndex())
         self.assertRaises(TypeError, asdouble, BadFloat())
         self.assertRaises(RuntimeError, asdouble, BadFloat3())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(asdouble(BadIndex2()), 1.)
+        self.assertRaises(TypeError, asdouble, BadIndex2())
         with self.assertWarns(DeprecationWarning):
             self.assertEqual(asdouble(BadFloat2()), 4.25)
         with warnings.catch_warnings():

Lib/test/test_capi/test_getargs.py

@@ -172,8 +172,7 @@ def test_b(self):
         self.assertEqual(99, getargs_b(Index()))
         self.assertEqual(0, getargs_b(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_b, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_b(BadIndex2()))
+        self.assertRaises(TypeError, getargs_b, BadIndex2())
         self.assertEqual(0, getargs_b(BadIndex3()))
         self.assertRaises(TypeError, getargs_b, Int())
         self.assertEqual(0, getargs_b(IntSubclass()))
@@ -196,8 +195,7 @@ def test_B(self):
         self.assertEqual(99, getargs_B(Index()))
         self.assertEqual(0, getargs_B(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_B, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_B(BadIndex2()))
+        self.assertRaises(TypeError, getargs_B, BadIndex2())
         self.assertEqual(0, getargs_B(BadIndex3()))
         self.assertRaises(TypeError, getargs_B, Int())
         self.assertEqual(0, getargs_B(IntSubclass()))
@@ -233,8 +231,7 @@ def test_H(self):
         self.assertEqual(99, getargs_H(Index()))
         self.assertEqual(0, getargs_H(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_H, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_H(BadIndex2()))
+        self.assertRaises(TypeError, getargs_H, BadIndex2())
         self.assertEqual(0, getargs_H(BadIndex3()))
         self.assertRaises(TypeError, getargs_H, Int())
         self.assertEqual(0, getargs_H(IntSubclass()))
@@ -265,8 +262,7 @@ def test_I(self):
         self.assertEqual(99, getargs_I(Index()))
         self.assertEqual(0, getargs_I(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_I, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_I(BadIndex2()))
+        self.assertRaises(TypeError, getargs_I, BadIndex2())
         self.assertEqual(0, getargs_I(BadIndex3()))
         self.assertRaises(TypeError, getargs_I, Int())
         self.assertEqual(0, getargs_I(IntSubclass()))
@@ -297,8 +293,7 @@ def test_k(self):
         self.assertEqual(99, getargs_k(Index()))
         self.assertEqual(0, getargs_k(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_k, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_k(BadIndex2()))
+        self.assertRaises(TypeError, getargs_k, BadIndex2())
         self.assertEqual(0, getargs_k(BadIndex3()))
         self.assertRaises(TypeError, getargs_k, Int())
         self.assertEqual(0, getargs_k(IntSubclass()))
@@ -330,8 +325,7 @@ def test_h(self):
         self.assertEqual(99, getargs_h(Index()))
         self.assertEqual(0, getargs_h(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_h, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_h(BadIndex2()))
+        self.assertRaises(TypeError, getargs_h, BadIndex2())
         self.assertEqual(0, getargs_h(BadIndex3()))
         self.assertRaises(TypeError, getargs_h, Int())
         self.assertEqual(0, getargs_h(IntSubclass()))
@@ -354,8 +348,7 @@ def test_i(self):
         self.assertEqual(99, getargs_i(Index()))
         self.assertEqual(0, getargs_i(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_i, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_i(BadIndex2()))
+        self.assertRaises(TypeError, getargs_i, BadIndex2())
         self.assertEqual(0, getargs_i(BadIndex3()))
         self.assertRaises(TypeError, getargs_i, Int())
         self.assertEqual(0, getargs_i(IntSubclass()))
@@ -378,8 +371,7 @@ def test_l(self):
         self.assertEqual(99, getargs_l(Index()))
         self.assertEqual(0, getargs_l(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_l, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_l(BadIndex2()))
+        self.assertRaises(TypeError, getargs_l, BadIndex2())
         self.assertEqual(0, getargs_l(BadIndex3()))
         self.assertRaises(TypeError, getargs_l, Int())
         self.assertEqual(0, getargs_l(IntSubclass()))
@@ -403,8 +395,7 @@ def test_n(self):
         self.assertEqual(99, getargs_n(Index()))
         self.assertEqual(0, getargs_n(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_n, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_n(BadIndex2()))
+        self.assertRaises(TypeError, getargs_n, BadIndex2())
         self.assertEqual(0, getargs_n(BadIndex3()))
         self.assertRaises(TypeError, getargs_n, Int())
         self.assertEqual(0, getargs_n(IntSubclass()))
@@ -431,8 +422,7 @@ def test_L(self):
         self.assertEqual(99, getargs_L(Index()))
         self.assertEqual(0, getargs_L(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_L, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_L(BadIndex2()))
+        self.assertRaises(TypeError, getargs_L, BadIndex2())
         self.assertEqual(0, getargs_L(BadIndex3()))
         self.assertRaises(TypeError, getargs_L, Int())
         self.assertEqual(0, getargs_L(IntSubclass()))
@@ -455,8 +445,7 @@ def test_K(self):
         self.assertEqual(99, getargs_K(Index()))
         self.assertEqual(0, getargs_K(IndexIntSubclass()))
         self.assertRaises(TypeError, getargs_K, BadIndex())
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(1, getargs_K(BadIndex2()))
+        self.assertRaises(TypeError, getargs_K, BadIndex2())
         self.assertEqual(0, getargs_K(BadIndex3()))
         self.assertRaises(TypeError, getargs_K, Int())
         self.assertEqual(0, getargs_K(IntSubclass()))

Lib/test/test_capi/test_number.py

@@ -263,11 +263,7 @@ def test_long(self):
         self.assertEqual(long(IntLike.with_val(99)), 99)
 
         self.assertRaises(TypeError, long, IntLike.with_val(1.0))
-        with warnings.catch_warnings():
-            warnings.simplefilter("error", DeprecationWarning)
-            self.assertRaises(DeprecationWarning, long, IntLike.with_val(True))
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(long(IntLike.with_val(True)), 1)
+        self.assertRaises(TypeError, long, IntLike.with_val(True))
         self.assertRaises(RuntimeError, long, IntLike.with_exc(RuntimeError))
 
         self.assertRaises(TypeError, long, 1j)
@@ -307,11 +303,7 @@ def test_index(self):
 
         self.assertEqual(index(11), 11)
 
-        with warnings.catch_warnings():
-            warnings.simplefilter("error", DeprecationWarning)
-            self.assertRaises(DeprecationWarning, index, IndexLike.with_val(True))
-        with self.assertWarns(DeprecationWarning):
-            self.assertEqual(index(IndexLike.with_val(True)), 1)
+        self.assertRaises(TypeError, index, IndexLike.with_val(True))
         self.assertRaises(TypeError, index, IndexLike.with_val(1.0))
         self.assertRaises(RuntimeError, index, IndexLike.with_exc(RuntimeError))
 

Lib/test/test_index.py

@@ -81,9 +81,7 @@ def __index__(self):
                 return True
 
         bad_int = BadInt()
-        with self.assertWarns(DeprecationWarning):
-            n = operator.index(bad_int)
-        self.assertEqual(n, 1)
+        self.assertRaises(TypeError, operator.index, bad_int)
 
         bad_int = BadInt2()
         n = operator.index(bad_int)

Lib/test/test_int.py

@@ -456,27 +456,21 @@ def __int__(self):
                 return True
 
         bad_int = BadIndex()
-        with self.assertWarns(DeprecationWarning):
-            n = int(bad_int)
-        self.assertEqual(n, 1)
-        self.assertIs(type(n), int)
+        with self.assertRaises(TypeError):
+            int(bad_int)
 
         bad_int = BadIndex2()
         n = int(bad_int)
         self.assertEqual(n, 0)
         self.assertIs(type(n), int)
 
         bad_int = BadInt()
-        with self.assertWarns(DeprecationWarning):
-            n = int(bad_int)
-        self.assertEqual(n, 1)
-        self.assertIs(type(n), int)
+        with self.assertRaises(TypeError):
+            int(bad_int)
 
         bad_int = BadInt2()
-        with self.assertWarns(DeprecationWarning):
-            n = int(bad_int)
-        self.assertEqual(n, 1)
-        self.assertIs(type(n), int)
+        with self.assertRaises(TypeError):
+            int(bad_int)
 
     def test_error_message(self):
         def check(s, base=None):

Misc/NEWS.d/next/Core_and_Builtins/2026-02-09-11-02-08.gh-issue-144584.nJs_21.rst

@@ -0,0 +1,2 @@
+Remove support for returning non-:class:`int` objects in
+:meth:`~object.__index__` and :meth:`~object.__int__`.

Objects/abstract.c

@@ -1428,24 +1428,11 @@ _PyNumber_Index(PyObject *item)
     if (!result || PyLong_CheckExact(result)) {
         return result;
     }
-
-    if (!PyLong_Check(result)) {
-        PyErr_Format(PyExc_TypeError,
-                     "%T.__index__() must return an int, not %T",
-                     item, result);
-        Py_DECREF(result);
-        return NULL;
-    }
-    /* Issue #17576: warn if 'result' not of exact type int. */
-    if (PyErr_WarnFormat(PyExc_DeprecationWarning, 1,
-            "%T.__index__() must return an int, not %T.  "
-            "The ability to return an instance of a strict subclass of int "
-            "is deprecated, and may be removed in a future version of Python.",
-            item, result)) {
-        Py_DECREF(result);
-        return NULL;
-    }
-    return result;
+    PyErr_Format(PyExc_TypeError,
+                 "%T.__index__() must return an int, not %T",
+                 item, result);
+    Py_DECREF(result);
+    return NULL;
 }
 
 /* Return an exact Python int from the object item.
@@ -1538,25 +1525,11 @@ PyNumber_Long(PyObject *o)
         if (!result || PyLong_CheckExact(result)) {
             return result;
         }
-
-        if (!PyLong_Check(result)) {
-            PyErr_Format(PyExc_TypeError,
-                         "%T.__int__() must return an int, not %T",
-                         o, result);
-            Py_DECREF(result);
-            return NULL;
-        }
-        /* Issue #17576: warn if 'result' not of exact type int. */
-        if (PyErr_WarnFormat(PyExc_DeprecationWarning, 1,
-                "%T.__int__() must return an int, not %T.  "
-                "The ability to return an instance of a strict subclass of int "
-                "is deprecated, and may be removed in a future version of Python.",
-                o, result)) {
-            Py_DECREF(result);
-            return NULL;
-        }
-        Py_SETREF(result, _PyLong_Copy((PyLongObject *)result));
-        return result;
+        PyErr_Format(PyExc_TypeError,
+                     "%T.__int__() must return an int, not %T",
+                     o, result);
+        Py_DECREF(result);
+        return NULL;
     }
     if (m && m->nb_index) {
         return PyNumber_Index(o);