From 61bdb0d31924ec5fd12aa8dbe197002c57dfbf82 Mon Sep 17 00:00:00 2001
From: Victor Stinner <victor.stinner@gmail.com>
Date: Fri, 9 Dec 2016 15:39:28 +0100
Subject: [PATCH] Use _PyObject_CallMethodIdObjArgs() in _io

Issue #28915: Replace _PyObject_CallMethodId() with
_PyObject_CallMethodIdObjArgs() when the format string was only made of "O"
formats, PyObject* arguments.

_PyObject_CallMethodIdObjArgs() avoids the creation of a temporary tuple and
doesn't have to parse a format string.
---
 Modules/_io/bufferedio.c   | 3 ++-
 Modules/_io/fileio.c       | 4 ++--
 Modules/_io/iobase.c       | 3 ++-
 Modules/_io/textio.c       | 8 +++++---
 Modules/_io/winconsoleio.c | 6 +++---
 5 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/Modules/_io/bufferedio.c b/Modules/_io/bufferedio.c
index 2b43fd859c5..cb4173e5981 100644
--- a/Modules/_io/bufferedio.c
+++ b/Modules/_io/bufferedio.c
@@ -454,7 +454,8 @@ buffered_dealloc_warn(buffered *self, PyObject *source)
 {
     if (self->ok && self->raw) {
         PyObject *r;
-        r = _PyObject_CallMethodId(self->raw, &PyId__dealloc_warn, "O", source);
+        r = _PyObject_CallMethodIdObjArgs(self->raw, &PyId__dealloc_warn,
+                                          source, NULL);
         if (r)
             Py_DECREF(r);
         else
diff --git a/Modules/_io/fileio.c b/Modules/_io/fileio.c
index 54cfb7fa7d6..69e35180d75 100644
--- a/Modules/_io/fileio.c
+++ b/Modules/_io/fileio.c
@@ -150,8 +150,8 @@ _io_FileIO_close_impl(fileio *self)
     PyObject *exc, *val, *tb;
     int rc;
     _Py_IDENTIFIER(close);
-    res = _PyObject_CallMethodId((PyObject*)&PyRawIOBase_Type,
-                                 &PyId_close, "O", self);
+    res = _PyObject_CallMethodIdObjArgs((PyObject*)&PyRawIOBase_Type,
+                                        &PyId_close, self, NULL);
     if (!self->closefd) {
         self->fd = -1;
         return res;
diff --git a/Modules/_io/iobase.c b/Modules/_io/iobase.c
index 472ef3b97cd..ee6ad474b59 100644
--- a/Modules/_io/iobase.c
+++ b/Modules/_io/iobase.c
@@ -661,7 +661,8 @@ _io__IOBase_readlines_impl(PyObject *self, Py_ssize_t hint)
            to remove the bytecode interpretation overhead, but it could
            probably be removed here. */
         _Py_IDENTIFIER(extend);
-        PyObject *ret = _PyObject_CallMethodId(result, &PyId_extend, "O", self);
+        PyObject *ret = _PyObject_CallMethodIdObjArgs(result, &PyId_extend,
+                                                      self, NULL);
 
         if (ret == NULL) {
             Py_DECREF(result);
diff --git a/Modules/_io/textio.c b/Modules/_io/textio.c
index d28f6139507..0a6dfe1b337 100644
--- a/Modules/_io/textio.c
+++ b/Modules/_io/textio.c
@@ -899,8 +899,8 @@ _io_TextIOWrapper___init___impl(textio *self, PyObject *buffer,
         PyObject *locale_module = _PyIO_get_locale_module(state);
         if (locale_module == NULL)
             goto catch_ImportError;
-        self->encoding = _PyObject_CallMethodId(
-            locale_module, &PyId_getpreferredencoding, "O", Py_False);
+        self->encoding = _PyObject_CallMethodIdObjArgs(
+            locale_module, &PyId_getpreferredencoding, Py_False, NULL);
         Py_DECREF(locale_module);
         if (self->encoding == NULL) {
           catch_ImportError:
@@ -2644,7 +2644,9 @@ _io_TextIOWrapper_close_impl(textio *self)
     else {
         PyObject *exc = NULL, *val, *tb;
         if (self->finalizing) {
-            res = _PyObject_CallMethodId(self->buffer, &PyId__dealloc_warn, "O", self);
+            res = _PyObject_CallMethodIdObjArgs(self->buffer,
+                                                &PyId__dealloc_warn,
+                                                self, NULL);
             if (res)
                 Py_DECREF(res);
             else
diff --git a/Modules/_io/winconsoleio.c b/Modules/_io/winconsoleio.c
index 7b00a9eb6d6..d8e43394bc6 100644
--- a/Modules/_io/winconsoleio.c
+++ b/Modules/_io/winconsoleio.c
@@ -85,7 +85,7 @@ char _PyIO_get_console_type(PyObject *path_or_fd) {
         Py_CLEAR(decoded);
         return '\0';
     }
-    decoded_upper = PyObject_CallMethod(decoded, "upper", "");
+    decoded_upper = PyObject_CallMethod(decoded, "upper", NULL);
     Py_CLEAR(decoded);
     if (!decoded_upper) {
         PyErr_Clear();
@@ -181,8 +181,8 @@ _io__WindowsConsoleIO_close_impl(winconsoleio *self)
     PyObject *exc, *val, *tb;
     int rc;
     _Py_IDENTIFIER(close);
-    res = _PyObject_CallMethodId((PyObject*)&PyRawIOBase_Type,
-                                 &PyId_close, "O", self);
+    res = _PyObject_CallMethodIdObjArgs((PyObject*)&PyRawIOBase_Type,
+                                        &PyId_close, self, NULL);
     if (!self->closehandle) {
         self->handle = INVALID_HANDLE_VALUE;
         return res;