bpo-37122: Make co->co_argcount represent the total number of positonal arguments in the code object (GH-13726)

2 files changed, 19 insertions, 35 deletions

diff --git a/Python/ceval.c b/Python/ceval.c
index f9ff4e0..d9a71e9 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -3757,10 +3757,10 @@ missing_arguments(PyThreadState *tstate, PyCodeObject *co,
         return;
     if (positional) {
         start = 0;
-        end = co->co_posonlyargcount + co->co_argcount - defcount;
+        end = co->co_argcount - defcount;
     }
     else {
-        start = co->co_posonlyargcount + co->co_argcount;
+        start = co->co_argcount;
         end = start + co->co_kwonlyargcount;
     }
     for (i = start; i < end; i++) {
@@ -3788,25 +3788,23 @@ too_many_positional(PyThreadState *tstate, PyCodeObject *co,
     Py_ssize_t kwonly_given = 0;
     Py_ssize_t i;
     PyObject *sig, *kwonly_sig;
-    Py_ssize_t co_posonlyargcount = co->co_posonlyargcount;
     Py_ssize_t co_argcount = co->co_argcount;
-    Py_ssize_t total_positional = co_argcount + co_posonlyargcount;
 
     assert((co->co_flags & CO_VARARGS) == 0);
     /* Count missing keyword-only args. */
-    for (i = total_positional; i < total_positional + co->co_kwonlyargcount; i++) {
+    for (i = co_argcount; i < co_argcount + co->co_kwonlyargcount; i++) {
         if (GETLOCAL(i) != NULL) {
             kwonly_given++;
         }
     }
     if (defcount) {
-        Py_ssize_t atleast = total_positional - defcount;
+        Py_ssize_t atleast = co_argcount - defcount;
         plural = 1;
-        sig = PyUnicode_FromFormat("from %zd to %zd", atleast, total_positional);
+        sig = PyUnicode_FromFormat("from %zd to %zd", atleast, co_argcount);
     }
     else {
-        plural = (total_positional != 1);
-        sig = PyUnicode_FromFormat("%zd", total_positional);
+        plural = (co_argcount != 1);
+        sig = PyUnicode_FromFormat("%zd", co_argcount);
     }
     if (sig == NULL)
         return;
@@ -3917,7 +3915,7 @@ _PyEval_EvalCodeWithName(PyObject *_co, PyObject *globals, PyObject *locals,
     PyObject *retval = NULL;
     PyObject **fastlocals, **freevars;
     PyObject *x, *u;
-    const Py_ssize_t total_args = co->co_argcount + co->co_kwonlyargcount + co->co_posonlyargcount;
+    const Py_ssize_t total_args = co->co_argcount + co->co_kwonlyargcount;
     Py_ssize_t i, j, n;
     PyObject *kwdict;
 
@@ -3953,9 +3951,9 @@ _PyEval_EvalCodeWithName(PyObject *_co, PyObject *globals, PyObject *locals,
         kwdict = NULL;
     }
 
-    /* Copy positional only arguments into local variables */
-    if (argcount > co->co_argcount + co->co_posonlyargcount) {
-        n = co->co_posonlyargcount;
+    /* Copy all positional arguments into local variables */
+    if (argcount > co->co_argcount) {
+        n = co->co_argcount;
     }
     else {
         n = argcount;
@@ -3966,20 +3964,6 @@ _PyEval_EvalCodeWithName(PyObject *_co, PyObject *globals, PyObject *locals,
         SETLOCAL(j, x);
     }
 
-
-    /* Copy positional arguments into local variables */
-    if (argcount > co->co_argcount + co->co_posonlyargcount) {
-        n += co->co_argcount;
-    }
-    else {
-        n = argcount;
-    }
-    for (i = j; i < n; i++) {
-        x = args[i];
-        Py_INCREF(x);
-        SETLOCAL(i, x);
-    }
-
     /* Pack other positional arguments into the *args argument */
     if (co->co_flags & CO_VARARGS) {
         u = _PyTuple_FromArray(args + n, argcount - n);
@@ -4059,14 +4043,14 @@ _PyEval_EvalCodeWithName(PyObject *_co, PyObject *globals, PyObject *locals,
     }
 
     /* Check the number of positional arguments */
-    if ((argcount > co->co_argcount + co->co_posonlyargcount) && !(co->co_flags & CO_VARARGS)) {
+    if ((argcount > co->co_argcount) && !(co->co_flags & CO_VARARGS)) {
         too_many_positional(tstate, co, argcount, defcount, fastlocals);
         goto fail;
     }
 
     /* Add missing positional arguments (copy default values from defs) */
-    if (argcount < co->co_posonlyargcount + co->co_argcount) {
-        Py_ssize_t m = co->co_posonlyargcount + co->co_argcount - defcount;
+    if (argcount < co->co_argcount) {
+        Py_ssize_t m = co->co_argcount - defcount;
         Py_ssize_t missing = 0;
         for (i = argcount; i < m; i++) {
             if (GETLOCAL(i) == NULL) {
@@ -4093,7 +4077,7 @@ _PyEval_EvalCodeWithName(PyObject *_co, PyObject *globals, PyObject *locals,
     /* Add missing keyword arguments (copy default values from kwdefs) */
     if (co->co_kwonlyargcount > 0) {
         Py_ssize_t missing = 0;
-        for (i = co->co_posonlyargcount + co->co_argcount; i < total_args; i++) {
+        for (i = co->co_argcount; i < total_args; i++) {
             PyObject *name;
             if (GETLOCAL(i) != NULL)
                 continue;
diff --git a/Python/compile.c b/Python/compile.c
index f6ec929..9e4a209 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -5764,7 +5764,7 @@ makecode(struct compiler *c, struct assembler *a)
     Py_ssize_t nlocals;
     int nlocals_int;
     int flags;
-    int argcount, posonlyargcount, kwonlyargcount, maxdepth;
+    int posorkeywordargcount, posonlyargcount, kwonlyargcount, maxdepth;
 
     consts = consts_dict_keys_inorder(c->u->u_consts);
     names = dict_keys_inorder(c->u->u_names, 0);
@@ -5808,15 +5808,15 @@ makecode(struct compiler *c, struct assembler *a)
         goto error;
     }
 
-    argcount = Py_SAFE_DOWNCAST(c->u->u_argcount, Py_ssize_t, int);
     posonlyargcount = Py_SAFE_DOWNCAST(c->u->u_posonlyargcount, Py_ssize_t, int);
+    posorkeywordargcount = Py_SAFE_DOWNCAST(c->u->u_argcount, Py_ssize_t, int);
     kwonlyargcount = Py_SAFE_DOWNCAST(c->u->u_kwonlyargcount, Py_ssize_t, int);
     maxdepth = stackdepth(c);
     if (maxdepth < 0) {
         goto error;
     }
-    co = PyCode_New(argcount, posonlyargcount, kwonlyargcount,
-                    nlocals_int, maxdepth, flags,
+    co = PyCode_New(posonlyargcount+posorkeywordargcount, posonlyargcount,
+                    kwonlyargcount, nlocals_int, maxdepth, flags,
                     bytecode, consts, names, varnames,
                     freevars, cellvars,
                     c->c_filename, c->u->u_name,