PEP 813: bring the implementation in line with the PEP draft

Doc/c-api/object.rst

@@ -397,6 +397,24 @@ Object Protocol
       This function now includes a debug assertion to help ensure that it
       does not silently discard an active exception.
 
+.. c:function:: PyObject* PyObject_Pretty(PyObject *o, PyObject *printer)
+
+   Pretty print *o* with *printer*, and return the result as a string.  This
+   is the equivalent of the Python expression ``f'{o!p:{printer}}'``, or
+   ``f'{o!p}'`` when *printer* is ``NULL``.
+
+   *printer* is called with *o*, and must return an iterable of strings, one
+   for each line of output.  The lines are joined with ``'\n'``, with no
+   trailing newline.  If *printer* is ``NULL``, a default printer is used.  It
+   calls *o*'s ``__pprint__()`` method if there is one, and interprets the
+   description that it returns.  Otherwise it uses :c:func:`PyObject_Repr`.
+
+   Raise :exc:`TypeError` if *printer* returns a :class:`str` rather than an
+   iterable of lines, or if any line is not a :class:`str`.
+
+   .. versionadded:: next
+
+
 .. c:function:: PyObject* PyObject_Bytes(PyObject *o)
 
    .. index:: pair: built-in function; bytes

Doc/data/refcounts.dat

@@ -1916,6 +1916,10 @@ PyObject_Size:PyObject*:o:0:
 PyObject_Str:PyObject*::+1:
 PyObject_Str:PyObject*:o:0:
 
+PyObject_Pretty:PyObject*::+1:
+PyObject_Pretty:PyObject*:o:0:
+PyObject_Pretty:PyObject*:printer:0:
+
 Py_TYPE:PyObject*::0:
 Py_TYPE:PyObject*:ob:0:
 

Include/internal/pycore_object.h

@@ -44,8 +44,6 @@ extern "C" {
    assert(_PyObject_CheckConsistency(obj, 1)); */
 extern int _PyObject_CheckConsistency(PyObject *op, int check_content);
 
-// Export for shared _testinternalcapi extension
-PyAPI_FUNC(PyObject *) _PyObject_Pretty(PyObject *obj, PyObject *printer);
 extern PyObject *_PyObject_CallPprintHelper(PyObject *obj, const char *name);
 #define _PyObject_PPRINT_METHOD(func, helper) \
     static PyObject *func(PyObject *self, PyObject *Py_UNUSED(ignored)) \

Include/object.h

@@ -394,6 +394,7 @@ PyAPI_FUNC(void) PyType_Modified(PyTypeObject *);
 /* Generic operations on objects */
 PyAPI_FUNC(PyObject *) PyObject_Repr(PyObject *);
 PyAPI_FUNC(PyObject *) PyObject_Str(PyObject *);
+PyAPI_FUNC(PyObject *) PyObject_Pretty(PyObject *, PyObject *);
 PyAPI_FUNC(PyObject *) PyObject_ASCII(PyObject *);
 PyAPI_FUNC(PyObject *) PyObject_Bytes(PyObject *);
 PyAPI_FUNC(PyObject *) PyObject_RichCompare(PyObject *, PyObject *, int);