bpo-40792: Make the result of PyNumber_Index() always having exact type int. (GH-20443)

Previously, the result could have been an instance of a subclass of int.

Also revert bpo-26202 and make attributes start, stop and step of the range
object having exact type int.

Add private function _PyNumber_Index() which preserves the old behavior
of PyNumber_Index() for performance to use it in the conversion functions
like PyLong_AsLong().

5 files changed, 15 insertions, 15 deletions

diff --git a/Modules/_io/clinic/bufferedio.c.h b/Modules/_io/clinic/bufferedio.c.h
index 1961ed9..19543fd 100644
--- a/Modules/_io/clinic/bufferedio.c.h
+++ b/Modules/_io/clinic/bufferedio.c.h
@@ -122,7 +122,7 @@ _io__Buffered_peek(buffered *self, PyObject *const *args, Py_ssize_t nargs)
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(args[0]);
+        PyObject *iobj = _PyNumber_Index(args[0]);
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -197,7 +197,7 @@ _io__Buffered_read1(buffered *self, PyObject *const *args, Py_ssize_t nargs)
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(args[0]);
+        PyObject *iobj = _PyNumber_Index(args[0]);
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -421,7 +421,7 @@ _io_BufferedReader___init__(PyObject *self, PyObject *args, PyObject *kwargs)
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(fastargs[1]);
+        PyObject *iobj = _PyNumber_Index(fastargs[1]);
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -475,7 +475,7 @@ _io_BufferedWriter___init__(PyObject *self, PyObject *args, PyObject *kwargs)
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(fastargs[1]);
+        PyObject *iobj = _PyNumber_Index(fastargs[1]);
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -567,7 +567,7 @@ _io_BufferedRWPair___init__(PyObject *self, PyObject *args, PyObject *kwargs)
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(PyTuple_GET_ITEM(args, 2));
+        PyObject *iobj = _PyNumber_Index(PyTuple_GET_ITEM(args, 2));
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -621,7 +621,7 @@ _io_BufferedRandom___init__(PyObject *self, PyObject *args, PyObject *kwargs)
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(fastargs[1]);
+        PyObject *iobj = _PyNumber_Index(fastargs[1]);
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -637,4 +637,4 @@ skip_optional_pos:
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=1882bb497ddc9375 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=98ccf7610c0e82ba input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/bytesio.c.h b/Modules/_io/clinic/bytesio.c.h
index 4720bdd..5ea80ae 100644
--- a/Modules/_io/clinic/bytesio.c.h
+++ b/Modules/_io/clinic/bytesio.c.h
@@ -404,7 +404,7 @@ _io_BytesIO_seek(bytesio *self, PyObject *const *args, Py_ssize_t nargs)
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(args[0]);
+        PyObject *iobj = _PyNumber_Index(args[0]);
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -505,4 +505,4 @@ skip_optional_pos:
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=ba0f302f16397741 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=49a32140eb8c5555 input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/iobase.c.h b/Modules/_io/clinic/iobase.c.h
index 02a2ab8..4fd6e18 100644
--- a/Modules/_io/clinic/iobase.c.h
+++ b/Modules/_io/clinic/iobase.c.h
@@ -276,7 +276,7 @@ _io__RawIOBase_read(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(args[0]);
+        PyObject *iobj = _PyNumber_Index(args[0]);
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -310,4 +310,4 @@ _io__RawIOBase_readall(PyObject *self, PyObject *Py_UNUSED(ignored))
 {
     return _io__RawIOBase_readall_impl(self);
 }
-/*[clinic end generated code: output=1f9ce590549593be input=a9049054013a1b77]*/
+/*[clinic end generated code: output=83c1361a7a51ca84 input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/stringio.c.h b/Modules/_io/clinic/stringio.c.h
index 2b32319..147ef66 100644
--- a/Modules/_io/clinic/stringio.c.h
+++ b/Modules/_io/clinic/stringio.c.h
@@ -179,7 +179,7 @@ _io_StringIO_seek(stringio *self, PyObject *const *args, Py_ssize_t nargs)
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(args[0]);
+        PyObject *iobj = _PyNumber_Index(args[0]);
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -338,4 +338,4 @@ _io_StringIO_seekable(stringio *self, PyObject *Py_UNUSED(ignored))
 {
     return _io_StringIO_seekable_impl(self);
 }
-/*[clinic end generated code: output=9c428b2942d54991 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=eea93dcab10d0a97 input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/textio.c.h b/Modules/_io/clinic/textio.c.h
index f0ad69c..0b047ac 100644
--- a/Modules/_io/clinic/textio.c.h
+++ b/Modules/_io/clinic/textio.c.h
@@ -452,7 +452,7 @@ _io_TextIOWrapper_readline(textio *self, PyObject *const *args, Py_ssize_t nargs
     }
     {
         Py_ssize_t ival = -1;
-        PyObject *iobj = PyNumber_Index(args[0]);
+        PyObject *iobj = _PyNumber_Index(args[0]);
         if (iobj != NULL) {
             ival = PyLong_AsSsize_t(iobj);
             Py_DECREF(iobj);
@@ -671,4 +671,4 @@ _io_TextIOWrapper_close(textio *self, PyObject *Py_UNUSED(ignored))
 {
     return _io_TextIOWrapper_close_impl(self);
 }
-/*[clinic end generated code: output=ea96ee1eb3a71f77 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=2604c8f3a45b9a03 input=a9049054013a1b77]*/