Issue #26057: Got rid of nonneeded use of PyUnicode_FromObject().

Modules/socketmodule.c

@@ -1401,7 +1401,7 @@ static int
 idna_converter(PyObject *obj, struct maybe_idna *data)
 {
     size_t len;
-    PyObject *obj2, *obj3;
+    PyObject *obj2;
     if (obj == NULL) {
         idna_cleanup(data);
         return 1;
@@ -1416,31 +1416,27 @@ idna_converter(PyObject *obj, struct maybe_idna *data)
         data->buf = PyByteArray_AsString(obj);
         len = PyByteArray_Size(obj);
     }
-    else if (PyUnicode_Check(obj) && PyUnicode_READY(obj) == 0 && PyUnicode_IS_COMPACT_ASCII(obj)) {
-        data->buf = PyUnicode_DATA(obj);
-        len = PyUnicode_GET_LENGTH(obj);
-    }
-    else {
-        obj2 = PyUnicode_FromObject(obj);
-        if (!obj2) {
-            PyErr_Format(PyExc_TypeError, "string or unicode text buffer expected, not %s",
-                         obj->ob_type->tp_name);
-            return 0;
+    else if (PyUnicode_Check(obj)) {
+        if (PyUnicode_READY(obj) == 0 && PyUnicode_IS_COMPACT_ASCII(obj)) {
+            data->buf = PyUnicode_DATA(obj);
+            len = PyUnicode_GET_LENGTH(obj);
         }
-        obj3 = PyUnicode_AsEncodedString(obj2, "idna", NULL);
-        Py_DECREF(obj2);
-        if (!obj3) {
-            PyErr_SetString(PyExc_TypeError, "encoding of hostname failed");
-            return 0;
-        }
-        if (!PyBytes_Check(obj3)) {
-            Py_DECREF(obj3);
-            PyErr_SetString(PyExc_TypeError, "encoding of hostname failed to return bytes");
-            return 0;
+        else {
+            obj2 = PyUnicode_AsEncodedString(obj, "idna", NULL);
+            if (!obj2) {
+                PyErr_SetString(PyExc_TypeError, "encoding of hostname failed");
+                return 0;
+            }
+            assert(PyBytes_Check(obj2));
+            data->obj = obj2;
+            data->buf = PyBytes_AS_STRING(obj2);
+            len = PyBytes_GET_SIZE(obj2);
         }
-        data->obj = obj3;
-        data->buf = PyBytes_AS_STRING(obj3);
-        len = PyBytes_GET_SIZE(obj3);
+    }
+    else {
+        PyErr_Format(PyExc_TypeError, "str, bytes or bytearray expected, not %s",
+                     obj->ob_type->tp_name);
+        return 0;
     }
     if (strlen(data->buf) != len) {
         Py_CLEAR(data->obj);

Objects/stringlib/find.h

@@ -123,11 +123,6 @@ STRINGLIB(parse_args_finds)(const char * function_name, PyObject *args,
 /*
 Wraps stringlib_parse_args_finds() and additionally ensures that the
 first argument is a unicode object.
-
-Note that we receive a pointer to the pointer of the substring object,
-so when we create that object in this function we don't DECREF it,
-because it continues living in the caller functions (those functions,
-after finishing using the substring, must DECREF it).
 */
 
 Py_LOCAL_INLINE(int)
@@ -135,14 +130,10 @@ STRINGLIB(parse_args_finds_unicode)(const char * function_name, PyObject *args,
                                    PyObject **substring,
                                    Py_ssize_t *start, Py_ssize_t *end)
 {
-    PyObject *tmp_substring;
-
-    if(STRINGLIB(parse_args_finds)(function_name, args, &tmp_substring,
+    if(STRINGLIB(parse_args_finds)(function_name, args, substring,
                                   start, end)) {
-        tmp_substring = PyUnicode_FromObject(tmp_substring);
-        if (!tmp_substring)
+        if (ensure_unicode(*substring) < 0)
             return 0;
-        *substring = tmp_substring;
         return 1;
     }
     return 0;

Python/bltinmodule.c

@@ -1931,9 +1931,8 @@ builtin_input_impl(PyModuleDef *module, PyObject *prompt)
             Py_CLEAR(stringpo);
             if (po == NULL)
                 goto _readline_errors;
-            promptstr = PyBytes_AsString(po);
-            if (promptstr == NULL)
-                goto _readline_errors;
+            assert(PyBytes_Check(po));
+            promptstr = PyBytes_AS_STRING(po);
         }
         else {
             po = NULL;

Python/getargs.c

@@ -1056,35 +1056,25 @@ convertsimple(PyObject *arg, const char **p_format, va_list *p_va, int flags,
                 return converterr("(AsCharBuffer failed)",
                                   arg, msgbuf, bufsize);
         }
-        else {
-            PyObject *u;
-
-            /* Convert object to Unicode */
-            u = PyUnicode_FromObject(arg);
-            if (u == NULL)
-                return converterr(
-                    "string or unicode or text buffer",
-                    arg, msgbuf, bufsize);
-
+        else if (PyUnicode_Check(arg)) {
             /* Encode object; use default error handling */
-            s = PyUnicode_AsEncodedString(u,
+            s = PyUnicode_AsEncodedString(arg,
                                           encoding,
                                           NULL);
-            Py_DECREF(u);
             if (s == NULL)
                 return converterr("(encoding failed)",
                                   arg, msgbuf, bufsize);
-            if (!PyBytes_Check(s)) {
-                Py_DECREF(s);
-                return converterr(
-                    "(encoder failed to return bytes)",
-                    arg, msgbuf, bufsize);
-            }
+            assert(PyBytes_Check(s));
             size = PyBytes_GET_SIZE(s);
             ptr = PyBytes_AS_STRING(s);
             if (ptr == NULL)
                 ptr = "";
         }
+        else {
+            return converterr(
+                recode_strings ? "str" : "str, bytes or bytearray",
+                arg, msgbuf, bufsize);
+        }
 
         /* Write output; output is guaranteed to be 0-terminated */
         if (*format == '#') {