bpo-41559: Change PEP 612 implementation to pure Python (#25449)
diff --git a/Objects/genericaliasobject.c b/Objects/genericaliasobject.c
index 8fae83b..756a7ce 100644
--- a/Objects/genericaliasobject.c
+++ b/Objects/genericaliasobject.c
@@ -156,25 +156,13 @@ ga_repr(PyObject *self)
return NULL;
}
-/* Checks if a variable number of names are from typing.py.
-* If any one of the names are found, return 1, else 0.
-**/
-static inline int
-is_typing_name(PyObject *obj, int num, ...)
+// isinstance(obj, TypeVar) without importing typing.py.
+// Returns -1 for errors.
+static int
+is_typevar(PyObject *obj)
{
- va_list names;
- va_start(names, num);
-
PyTypeObject *type = Py_TYPE(obj);
- int hit = 0;
- for (int i = 0; i < num; ++i) {
- if (!strcmp(type->tp_name, va_arg(names, const char *))) {
- hit = 1;
- break;
- }
- }
- va_end(names);
- if (!hit) {
+ if (strcmp(type->tp_name, "TypeVar") != 0) {
return 0;
}
PyObject *module = PyObject_GetAttrString((PyObject *)type, "__module__");
@@ -184,24 +172,9 @@ is_typing_name(PyObject *obj, int num, ...)
int res = PyUnicode_Check(module)
&& _PyUnicode_EqualToASCIIString(module, "typing");
Py_DECREF(module);
-
return res;
}
-// isinstance(obj, (TypeVar, ParamSpec)) without importing typing.py.
-// Returns -1 for errors.
-static inline int
-is_typevarlike(PyObject *obj)
-{
- return is_typing_name(obj, 2, "TypeVar", "ParamSpec");
-}
-
-static inline int
-is_paramspec(PyObject *obj)
-{
- return is_typing_name(obj, 1, "ParamSpec");
-}
-
// Index of item in self[:len], or -1 if not found (self is a tuple)
static Py_ssize_t
tuple_index(PyObject *self, Py_ssize_t len, PyObject *item)
@@ -236,7 +209,7 @@ make_parameters(PyObject *args)
Py_ssize_t iparam = 0;
for (Py_ssize_t iarg = 0; iarg < nargs; iarg++) {
PyObject *t = PyTuple_GET_ITEM(args, iarg);
- int typevar = is_typevarlike(t);
+ int typevar = is_typevar(t);
if (typevar < 0) {
Py_DECREF(parameters);
return NULL;
@@ -306,14 +279,7 @@ subs_tvars(PyObject *obj, PyObject *params, PyObject **argitems)
if (iparam >= 0) {
arg = argitems[iparam];
}
- // convert all the lists inside args to tuples to help
- // with caching in other libaries
- if (PyList_CheckExact(arg)) {
- arg = PyList_AsTuple(arg);
- }
- else {
- Py_INCREF(arg);
- }
+ Py_INCREF(arg);
PyTuple_SET_ITEM(subargs, i, arg);
}
@@ -348,19 +314,11 @@ ga_getitem(PyObject *self, PyObject *item)
int is_tuple = PyTuple_Check(item);
Py_ssize_t nitems = is_tuple ? PyTuple_GET_SIZE(item) : 1;
PyObject **argitems = is_tuple ? &PyTuple_GET_ITEM(item, 0) : &item;
- // A special case in PEP 612 where if X = Callable[P, int],
- // then X[int, str] == X[[int, str]].
- if (nparams == 1 && nitems > 1 && is_tuple &&
- is_paramspec(PyTuple_GET_ITEM(alias->parameters, 0))) {
- argitems = &item;
- }
- else {
- if (nitems != nparams) {
- return PyErr_Format(PyExc_TypeError,
- "Too %s arguments for %R",
- nitems > nparams ? "many" : "few",
- self);
- }
+ if (nitems != nparams) {
+ return PyErr_Format(PyExc_TypeError,
+ "Too %s arguments for %R",
+ nitems > nparams ? "many" : "few",
+ self);
}
/* Replace all type variables (specified by alias->parameters)
with corresponding values specified by argitems.
@@ -375,7 +333,7 @@ ga_getitem(PyObject *self, PyObject *item)
}
for (Py_ssize_t iarg = 0; iarg < nargs; iarg++) {
PyObject *arg = PyTuple_GET_ITEM(alias->args, iarg);
- int typevar = is_typevarlike(arg);
+ int typevar = is_typevar(arg);
if (typevar < 0) {
Py_DECREF(newargs);
return NULL;
@@ -384,13 +342,7 @@ ga_getitem(PyObject *self, PyObject *item)
Py_ssize_t iparam = tuple_index(alias->parameters, nparams, arg);
assert(iparam >= 0);
arg = argitems[iparam];
- // convert lists to tuples to help with caching in other libaries.
- if (PyList_CheckExact(arg)) {
- arg = PyList_AsTuple(arg);
- }
- else {
- Py_INCREF(arg);
- }
+ Py_INCREF(arg);
}
else {
arg = subs_tvars(arg, alias->parameters, argitems);