bpo-37221: Add PyCode_NewWithPosOnlyArgs to be used internally and set PyCode_New as a compatibility wrapper (GH-13959)

Add PyCode_NewEx to be used internally and set PyCode_New as a compatibility wrapper

Author: pablogsal

Doc/c-api/code.rst

@@ -33,20 +33,21 @@ bound into a function.
 
    Return the number of free variables in *co*.
 
-.. c:function:: PyCodeObject* PyCode_New(int argcount, int posonlyargcount, int kwonlyargcount, int nlocals, int stacksize, int flags, PyObject *code, PyObject *consts, PyObject *names, PyObject *varnames, PyObject *freevars, PyObject *cellvars, PyObject *filename, PyObject *name, int firstlineno, PyObject *lnotab)
+.. c:function:: PyCodeObject* PyCode_New(int argcount, int kwonlyargcount, int nlocals, int stacksize, int flags, PyObject *code, PyObject *consts, PyObject *names, PyObject *varnames, PyObject *freevars, PyObject *cellvars, PyObject *filename, PyObject *name, int firstlineno, PyObject *lnotab)
 
-   Return a new code object.  If you need a dummy code object to
-   create a frame, use :c:func:`PyCode_NewEmpty` instead.  Calling
-   :c:func:`PyCode_New` directly can bind you to a precise Python
-   version since the definition of the bytecode changes often.
-
-   .. versionchanged:: 3.8
-      An extra parameter is required (*posonlyargcount*) to support :PEP:`570`.
-      The first parameter (*argcount*) now represents the total number of positional arguments,
-      including positional-only.
+   Return a new code object.  If you need a dummy code object to create a frame,
+   use :c:func:`PyCode_NewEmpty` instead.  Calling :c:func:`PyCode_New` directly
+   can bind you to a precise Python version since the definition of the bytecode
+   changes often.
 
    .. audit-event:: code.__new__ code,filename,name,argcount,posonlyargcount,kwonlyargcount,nlocals,stacksize,flags c.PyCode_New
 
+.. c:function:: PyCodeObject* PyCode_NewWithPosOnlyArgs(int argcount, int posonlyargcount, int kwonlyargcount, int nlocals, int stacksize, int flags, PyObject *code, PyObject *consts, PyObject *names, PyObject *varnames, PyObject *freevars, PyObject *cellvars, PyObject *filename, PyObject *name, int firstlineno, PyObject *lnotab)
+
+   Similar to :c:func:`PyCode_New`, but with an extra "posonlyargcount" for positonal-only arguments.
+
+   .. versionadded:: 3.8
+
 .. c:function:: PyCodeObject* PyCode_NewEmpty(const char *filename, const char *funcname, int firstlineno)
 
    Return a new empty code object with the specified filename,

Doc/data/refcounts.dat

@@ -234,9 +234,26 @@ PyCode_Check:PyObject*:co:0:
 PyCode_GetNumFree:int:::
 PyCode_GetNumFree:PyCodeObject*:co:0:
 
+PyCode_NewWithPosOnlyArgs:PyCodeObject*::+1:
+PyCode_NewWithPosOnlyArgs:int:argcount::
+PyCode_NewWithPosOnlyArgs:int:posonlyargcount::
+PyCode_NewWithPosOnlyArgs:int:kwonlyargcount::
+PyCode_NewWithPosOnlyArgs:int:nlocals::
+PyCode_NewWithPosOnlyArgs:int:stacksize::
+PyCode_NewWithPosOnlyArgs:int:flags::
+PyCode_NewWithPosOnlyArgs:PyObject*:code:0:
+PyCode_NewWithPosOnlyArgs:PyObject*:consts:0:
+PyCode_NewWithPosOnlyArgs:PyObject*:names:0:
+PyCode_NewWithPosOnlyArgs:PyObject*:varnames:0:
+PyCode_NewWithPosOnlyArgs:PyObject*:freevars:0:
+PyCode_NewWithPosOnlyArgs:PyObject*:cellvars:0:
+PyCode_NewWithPosOnlyArgs:PyObject*:filename:0:
+PyCode_NewWithPosOnlyArgs:PyObject*:name:0:
+PyCode_NewWithPosOnlyArgs:int:firstlineno::
+PyCode_NewWithPosOnlyArgs:PyObject*:lnotab:0:
+
 PyCode_New:PyCodeObject*::+1:
 PyCode_New:int:argcount::
-PyCode_New:int:posonlyargcount::
 PyCode_New:int:kwonlyargcount::
 PyCode_New:int:nlocals::
 PyCode_New:int:stacksize::

Doc/whatsnew/3.8.rst

@@ -1045,6 +1045,11 @@ Build and C API Changes
   allocation or deallocation may need to be adjusted.
   (Contributed by Eddie Elizondo in :issue:`35810`.)
 
+* The new function :c:func:`PyCode_NewWithPosOnlyArgs` allows to create
+  code objects like :c:func:`PyCode_New`, but with an extra *posonlyargcount*
+  parameter for indicating the number of positional-only arguments.
+  (Contributed by Pablo Galindo in :issue:`37221`.)
+
 
 Deprecated
 ==========

Include/code.h

@@ -120,6 +120,11 @@ PyAPI_DATA(PyTypeObject) PyCode_Type;
 
 /* Public interface */
 PyAPI_FUNC(PyCodeObject *) PyCode_New(
+        int, int, int, int, int, PyObject *, PyObject *,
+        PyObject *, PyObject *, PyObject *, PyObject *,
+        PyObject *, PyObject *, int, PyObject *);
+
+PyAPI_FUNC(PyCodeObject *) PyCode_NewWithPosOnlyArgs(
         int, int, int, int, int, int, PyObject *, PyObject *,
         PyObject *, PyObject *, PyObject *, PyObject *,
         PyObject *, PyObject *, int, PyObject *);

Misc/NEWS.d/next/C API/2019-06-11-02-50-38.bpo-37221.4tClQT.rst

@@ -0,0 +1,3 @@
+The new function :c:func:`PyCode_NewWithPosOnlyArgs` allows to create
+code objects like :c:func:`PyCode_New`, but with an extra *posonlyargcount*
+parameter for indicating the number of positonal-only arguments.

Objects/codeobject.c

@@ -102,14 +102,13 @@ intern_string_constants(PyObject *tuple)
     return modified;
 }
 
-
 PyCodeObject *
-PyCode_New(int argcount, int posonlyargcount, int kwonlyargcount,
-           int nlocals, int stacksize, int flags,
-           PyObject *code, PyObject *consts, PyObject *names,
-           PyObject *varnames, PyObject *freevars, PyObject *cellvars,
-           PyObject *filename, PyObject *name, int firstlineno,
-           PyObject *lnotab)
+PyCode_NewWithPosOnlyArgs(int argcount, int posonlyargcount, int kwonlyargcount,
+                          int nlocals, int stacksize, int flags,
+                          PyObject *code, PyObject *consts, PyObject *names,
+                          PyObject *varnames, PyObject *freevars, PyObject *cellvars,
+                          PyObject *filename, PyObject *name, int firstlineno,
+                          PyObject *lnotab)
 {
     PyCodeObject *co;
     Py_ssize_t *cell2arg = NULL;
@@ -243,6 +242,20 @@ PyCode_New(int argcount, int posonlyargcount, int kwonlyargcount,
     return co;
 }
 
+PyCodeObject *
+PyCode_New(int argcount, int kwonlyargcount,
+           int nlocals, int stacksize, int flags,
+           PyObject *code, PyObject *consts, PyObject *names,
+           PyObject *varnames, PyObject *freevars, PyObject *cellvars,
+           PyObject *filename, PyObject *name, int firstlineno,
+           PyObject *lnotab)
+{
+    return PyCode_NewWithPosOnlyArgs(argcount, 0, kwonlyargcount, nlocals,
+                                     stacksize, flags, code, consts, names,
+                                     varnames, freevars, cellvars, filename,
+                                     name, firstlineno, lnotab);
+}
+
 int
 _PyCode_InitOpcache(PyCodeObject *co)
 {
@@ -311,7 +324,8 @@ PyCode_NewEmpty(const char *filename, const char *funcname, int firstlineno)
     if (filename_ob == NULL)
         goto failed;
 
-    result = PyCode_New(0,                      /* argcount */
+    result = PyCode_NewWithPosOnlyArgs(
+                0,                    /* argcount */
                 0,                              /* posonlyargcount */
                 0,                              /* kwonlyargcount */
                 0,                              /* nlocals */
@@ -492,12 +506,14 @@ code_new(PyTypeObject *type, PyObject *args, PyObject *kw)
     if (ourcellvars == NULL)
         goto cleanup;
 
-    co = (PyObject *)PyCode_New(argcount, posonlyargcount, kwonlyargcount,
-                                nlocals, stacksize, flags,
-                                code, consts, ournames, ourvarnames,
-                                ourfreevars, ourcellvars, filename,
-                                name, firstlineno, lnotab);
-  cleanup:
+    co = (PyObject *)PyCode_NewWithPosOnlyArgs(argcount, posonlyargcount,
+                                               kwonlyargcount,
+                                               nlocals, stacksize, flags,
+                                               code, consts, ournames,
+                                               ourvarnames, ourfreevars,
+                                               ourcellvars, filename,
+                                               name, firstlineno, lnotab);
+  cleanup: 
     Py_XDECREF(ournames);
     Py_XDECREF(ourvarnames);
     Py_XDECREF(ourfreevars);
@@ -625,7 +641,7 @@ code_replace_impl(PyCodeObject *self, int co_argcount,
 
 #undef CHECK_INT_ARG
 
-    return (PyObject *)PyCode_New(
+    return (PyObject *)PyCode_NewWithPosOnlyArgs(
         co_argcount, co_posonlyargcount, co_kwonlyargcount, co_nlocals,
         co_stacksize, co_flags, (PyObject*)co_code, co_consts, co_names,
         co_varnames, co_freevars, co_cellvars, co_filename, co_name,

Python/compile.c

@@ -5813,13 +5813,11 @@ makecode(struct compiler *c, struct assembler *a)
     if (maxdepth < 0) {
         goto error;
     }
-    co = PyCode_New(posonlyargcount+posorkeywordargcount, posonlyargcount,
-                    kwonlyargcount, nlocals_int, maxdepth, flags,
-                    bytecode, consts, names, varnames,
-                    freevars, cellvars,
-                    c->c_filename, c->u->u_name,
-                    c->u->u_firstlineno,
-                    a->a_lnotab);
+    co = PyCode_NewWithPosOnlyArgs(posonlyargcount+posorkeywordargcount,
+                                   posonlyargcount, kwonlyargcount, nlocals_int, 
+                                   maxdepth, flags, bytecode, consts, names,
+                                   varnames, freevars, cellvars, c->c_filename,
+                                   c->u->u_name, c->u->u_firstlineno, a->a_lnotab);
  error:
     Py_XDECREF(consts);
     Py_XDECREF(names);

Python/marshal.c

@@ -1396,7 +1396,7 @@ r_object(RFILE *p)
             if (lnotab == NULL)
                 goto code_error;
 
-            v = (PyObject *) PyCode_New(
+            v = (PyObject *) PyCode_NewWithPosOnlyArgs(
                             argcount, posonlyargcount, kwonlyargcount,
                             nlocals, stacksize, flags,
                             code, consts, names, varnames,