address review: inline _PyLong_FromDigits & improve docs

Author: skirpichev

Doc/deprecations/c-api-pending-removal-in-3.18.rst

@@ -7,7 +7,8 @@ Pending removal in Python 3.18
   * :c:func:`!_PyDict_GetItemStringWithError`: use :c:func:`PyDict_GetItemStringRef`.
   * :c:func:`!_PyDict_Pop()`: :c:func:`PyDict_Pop`.
   * :c:func:`!_PyLong_Sign()`: use :c:func:`PyLong_GetSign`.
-  * :c:func:`!_PyLong_New`: use :c:func:`PyLongWriter_Create`.
+  * :c:func:`!_PyLong_FromDigits` and :c:func:`!_PyLong_New`:
+    use :c:func:`PyLongWriter_Create`.
   * :c:func:`!_PyThreadState_UncheckedGet`: use :c:func:`PyThreadState_GetUnchecked`.
   * :c:func:`!_PyUnicode_AsString`: use :c:func:`PyUnicode_AsUTF8`.
   * :c:func:`!_Py_HashPointer`: use :c:func:`Py_HashPointer`.

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

@@ -35,8 +35,6 @@ although there is currently no date scheduled for their removal.
 * :c:member:`!PyBytesObject.ob_shash` member:
   call :c:func:`PyObject_Hash` instead.
 * :c:member:`!PyDictObject.ma_version_tag` member.
-* :c:func::c:func:`!_PyLong_FromDigits`
-  Use instead :c:struct:`PyLongWriter` API.
 * Thread Local Storage (TLS) API:
 
   * :c:func:`PyThread_create_key`:

Doc/whatsnew/3.14.rst

@@ -1396,7 +1396,8 @@ Deprecated
   * :c:func:`!_PyDict_GetItemStringWithError`: use :c:func:`PyDict_GetItemStringRef`.
   * :c:func:`!_PyDict_Pop()`: use :c:func:`PyDict_Pop`.
   * :c:func:`!_PyLong_Sign()`: use :c:func:`PyLong_GetSign`.
-  * :c:func:`!_PyLong_New`: use :c:func:`PyLongWriter_Create`.
+  * :c:func:`!_PyLong_FromDigits` and :c:func:`!_PyLong_New`:
+    use :c:func:`PyLongWriter_Create`.
   * :c:func:`!_PyThreadState_UncheckedGet`: use :c:func:`PyThreadState_GetUnchecked`.
   * :c:func:`!_PyUnicode_AsString`: use :c:func:`PyUnicode_AsUTF8`.
   * :c:func:`!_Py_HashPointer`: use :c:func:`Py_HashPointer`.

Misc/NEWS.d/next/C_API/2024-12-14-10-14-27.gh-issue-127937.-tT1KP.rst

@@ -5,7 +5,8 @@ Python 3.18:
 * :c:func:`!_PyDict_GetItemStringWithError`: use :c:func:`PyDict_GetItemStringRef`.
 * :c:func:`!_PyDict_Pop()`: use :c:func:`PyDict_Pop`.
 * :c:func:`!_PyLong_Sign()`: use :c:func:`PyLong_GetSign`.
-* :c:func:`!_PyLong_New`: use :c:func:`PyLongWriter_Create`.
+* :c:func:`!_PyLong_FromDigits` and :c:func:`!_PyLong_New`:
+  use :c:func:`PyLongWriter_Create`.
 * :c:func:`!_PyThreadState_UncheckedGet`: use :c:func:`PyThreadState_GetUnchecked`.
 * :c:func:`!_PyUnicode_AsString`: use :c:func:`PyUnicode_AsUTF8`.
 * :c:func:`!_Py_HashPointer`: use :c:func:`Py_HashPointer`.

Misc/NEWS.d/next/C_API/2025-01-15-11-42-07.gh-issue-128863.C9MkB_.rst

@@ -224,8 +224,17 @@ _PyLong_Copy(PyLongObject *src)
             return get_small_int((sdigit)ival);
         }
     }
+
     Py_ssize_t size = _PyLong_DigitCount(src);
-    return (PyObject *)_PyLong_FromDigits(_PyLong_IsNegative(src), size, src->long_value.ob_digit);
+    PyLongObject *result = long_alloc(size);
+
+    if (result == NULL) {
+        PyErr_NoMemory();
+        return NULL;
+    }
+    _PyLong_SetSignAndDigitCount(result, _PyLong_Sign(src), size);
+    memcpy(result->long_value.ob_digit, src->long_value.ob_digit, size * sizeof(digit));
+    return (PyObject *)result;
 }
 
 static PyObject *