Mirror
/
cpython
mirror of https://github.com/python/cpython
4
1
Fork 0
Code Issues Releases Wiki Activity

bpo-43224: Implement substitution of unpacked TypeVarTuple in C (GH-31828) 

Co-authored-by: Matthew Rahtz <mrahtz@gmail.com>
This commit is contained in:
Serhiy Storchaka 2022-04-30 08:22:46 +03:00 committed by GitHub
parent a29aa76a3f
commit e8c2f72b94
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
5 changed files with 152 additions and 41 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
Include/internal/pycore_global_strings.h
View File

@ -202,6 +202,7 @@ struct _Py_global_strings {
STRUCT_FOR_ID(__truediv__) STRUCT_FOR_ID(__truediv__)
STRUCT_FOR_ID(__trunc__) STRUCT_FOR_ID(__trunc__)
STRUCT_FOR_ID(__typing_subst__) STRUCT_FOR_ID(__typing_subst__)
STRUCT_FOR_ID(__typing_unpacked__)
STRUCT_FOR_ID(__warningregistry__) STRUCT_FOR_ID(__warningregistry__)
STRUCT_FOR_ID(__weakref__) STRUCT_FOR_ID(__weakref__)
STRUCT_FOR_ID(__xor__) STRUCT_FOR_ID(__xor__)

1
Include/internal/pycore_runtime_init.h
View File

@ -825,6 +825,7 @@ extern "C" {
INIT_ID(__truediv__), \ INIT_ID(__truediv__), \
INIT_ID(__trunc__), \ INIT_ID(__trunc__), \
INIT_ID(__typing_subst__), \ INIT_ID(__typing_subst__), \
INIT_ID(__typing_unpacked__), \
INIT_ID(__warningregistry__), \ INIT_ID(__warningregistry__), \
INIT_ID(__weakref__), \ INIT_ID(__weakref__), \
INIT_ID(__xor__), \ INIT_ID(__xor__), \

63
Lib/test/test_typing.py
View File

@ -754,89 +754,89 @@ class GenericAliasSubstitutionTests(BaseTestCase):
tests = [ tests = [
# Alias # Args # Expected result # Alias # Args # Expected result
('C[*Ts]', '[()]', 'C[()]'), ('C[*Ts]', '[()]', 'C[()]'),
('tuple[*Ts]', '[()]', 'TypeError'), # Should be tuple[()] ('tuple[*Ts]', '[()]', 'tuple[()]'),
('Tuple[*Ts]', '[()]', 'Tuple[()]'), ('Tuple[*Ts]', '[()]', 'Tuple[()]'),
('C[*Ts]', '[int]', 'C[int]'), ('C[*Ts]', '[int]', 'C[int]'),
('tuple[*Ts]', '[int]', 'tuple[(int,),]'), # Should be tuple[int] ('tuple[*Ts]', '[int]', 'tuple[int]'),
('Tuple[*Ts]', '[int]', 'Tuple[int]'), ('Tuple[*Ts]', '[int]', 'Tuple[int]'),
('C[*Ts]', '[int, str]', 'C[int, str]'), ('C[*Ts]', '[int, str]', 'C[int, str]'),
('tuple[*Ts]', '[int, str]', 'TypeError'), # Should be tuple[int, str] ('tuple[*Ts]', '[int, str]', 'tuple[int, str]'),
('Tuple[*Ts]', '[int, str]', 'Tuple[int, str]'), ('Tuple[*Ts]', '[int, str]', 'Tuple[int, str]'),
('C[*Ts]', '[*tuple_type[int]]', 'C[*tuple_type[int]]'), # Should be C[int] ('C[*Ts]', '[*tuple_type[int]]', 'C[*tuple_type[int]]'), # Should be C[int]
('tuple[*Ts]', '[*tuple_type[int]]', 'tuple[(*tuple_type[int],),]'), # Should be tuple[int] ('tuple[*Ts]', '[*tuple_type[int]]', 'tuple[*tuple_type[int]]'), # Should be tuple[int]
('Tuple[*Ts]', '[*tuple_type[int]]', 'Tuple[*tuple_type[int]]'), # Should be Tuple[int] ('Tuple[*Ts]', '[*tuple_type[int]]', 'Tuple[*tuple_type[int]]'), # Should be Tuple[int]
('C[*Ts]', '[*tuple_type[*Ts]]', 'C[*tuple_type[*Ts]]'), # Should be C[*Ts] ('C[*Ts]', '[*tuple_type[*Ts]]', 'C[*tuple_type[*Ts]]'), # Should be C[*Ts]
('tuple[*Ts]', '[*tuple_type[*Ts]]', 'tuple[(*tuple_type[*Ts],),]'), # Should be tuple[*Ts] ('tuple[*Ts]', '[*tuple_type[*Ts]]', 'tuple[*tuple_type[*Ts]]'), # Should be tuple[*Ts]
('Tuple[*Ts]', '[*tuple_type[*Ts]]', 'Tuple[*tuple_type[*Ts]]'), # Should be Tuple[*Ts] ('Tuple[*Ts]', '[*tuple_type[*Ts]]', 'Tuple[*tuple_type[*Ts]]'), # Should be Tuple[*Ts]
('C[*Ts]', '[*tuple_type[int, str]]', 'C[*tuple_type[int, str]]'), # Should be C[int, str] ('C[*Ts]', '[*tuple_type[int, str]]', 'C[*tuple_type[int, str]]'), # Should be C[int, str]
('tuple[*Ts]', '[*tuple_type[int, str]]', 'tuple[(*tuple_type[int, str],),]'), # Should be tuple[int, str] ('tuple[*Ts]', '[*tuple_type[int, str]]', 'tuple[*tuple_type[int, str]]'), # Should be tuple[int, str]
('Tuple[*Ts]', '[*tuple_type[int, str]]', 'Tuple[*tuple_type[int, str]]'), # Should be Tuple[int, str] ('Tuple[*Ts]', '[*tuple_type[int, str]]', 'Tuple[*tuple_type[int, str]]'), # Should be Tuple[int, str]
('C[*Ts]', '[tuple_type[int, ...]]', 'C[tuple_type[int, ...]]'), ('C[*Ts]', '[tuple_type[int, ...]]', 'C[tuple_type[int, ...]]'),
('tuple[*Ts]', '[tuple_type[int, ...]]', 'tuple[(tuple_type[int, ...],),]'), # Should be tuple[tuple_type[int, ...]] ('tuple[*Ts]', '[tuple_type[int, ...]]', 'tuple[tuple_type[int, ...]]'),
('Tuple[*Ts]', '[tuple_type[int, ...]]', 'Tuple[tuple_type[int, ...]]'), ('Tuple[*Ts]', '[tuple_type[int, ...]]', 'Tuple[tuple_type[int, ...]]'),
('C[*Ts]', '[tuple_type[int, ...], tuple_type[str, ...]]', 'C[tuple_type[int, ...], tuple_type[str, ...]]'), ('C[*Ts]', '[tuple_type[int, ...], tuple_type[str, ...]]', 'C[tuple_type[int, ...], tuple_type[str, ...]]'),
('tuple[*Ts]', '[tuple_type[int, ...], tuple_type[str, ...]]', 'TypeError'), # Should be tuple[tuple_type[int, ...], tuple_type[str, ...]] ('tuple[*Ts]', '[tuple_type[int, ...], tuple_type[str, ...]]', 'tuple[tuple_type[int, ...], tuple_type[str, ...]]'),
('Tuple[*Ts]', '[tuple_type[int, ...], tuple_type[str, ...]]', 'Tuple[tuple_type[int, ...], tuple_type[str, ...]]'), ('Tuple[*Ts]', '[tuple_type[int, ...], tuple_type[str, ...]]', 'Tuple[tuple_type[int, ...], tuple_type[str, ...]]'),
('C[*Ts]', '[*tuple_type[int, ...]]', 'C[*tuple_type[int, ...]]'), ('C[*Ts]', '[*tuple_type[int, ...]]', 'C[*tuple_type[int, ...]]'),
('tuple[*Ts]', '[*tuple_type[int, ...]]', 'tuple[(*tuple_type[int, ...],),]'), # Should be tuple[*tuple_type[int, ...]] ('tuple[*Ts]', '[*tuple_type[int, ...]]', 'tuple[*tuple_type[int, ...]]'),
('Tuple[*Ts]', '[*tuple_type[int, ...]]', 'Tuple[*tuple_type[int, ...]]'), ('Tuple[*Ts]', '[*tuple_type[int, ...]]', 'Tuple[*tuple_type[int, ...]]'),
# Technically, multiple unpackings are forbidden by PEP 646, but we # Technically, multiple unpackings are forbidden by PEP 646, but we
# choose to be less restrictive at runtime, to allow folks room # choose to be less restrictive at runtime, to allow folks room
# to experiment. So all three of these should be valid. # to experiment. So all three of these should be valid.
('C[*Ts]', '[*tuple_type[int, ...], *tuple_type[str, ...]]', 'C[*tuple_type[int, ...], *tuple_type[str, ...]]'), ('C[*Ts]', '[*tuple_type[int, ...], *tuple_type[str, ...]]', 'C[*tuple_type[int, ...], *tuple_type[str, ...]]'),
# Should be tuple[*tuple_type[int, ...], *tuple_type[str, ...]], to match the other two. ('tuple[*Ts]', '[*tuple_type[int, ...], *tuple_type[str, ...]]', 'tuple[*tuple_type[int, ...], *tuple_type[str, ...]]'),
('tuple[*Ts]', '[*tuple_type[int, ...], *tuple_type[str, ...]]', 'TypeError'),
('Tuple[*Ts]', '[*tuple_type[int, ...], *tuple_type[str, ...]]', 'Tuple[*tuple_type[int, ...], *tuple_type[str, ...]]'), ('Tuple[*Ts]', '[*tuple_type[int, ...], *tuple_type[str, ...]]', 'Tuple[*tuple_type[int, ...], *tuple_type[str, ...]]'),
('C[*Ts]', '[*Ts]', 'C[*Ts]'), ('C[*Ts]', '[*Ts]', 'C[*Ts]'),
('tuple[*Ts]', '[*Ts]', 'tuple[(*Ts,),]'), # Should be tuple[*Ts] ('tuple[*Ts]', '[*Ts]', 'tuple[*Ts]'),
('Tuple[*Ts]', '[*Ts]', 'Tuple[*Ts]'), ('Tuple[*Ts]', '[*Ts]', 'Tuple[*Ts]'),
('C[*Ts]', '[T, *Ts]', 'C[T, *Ts]'), ('C[*Ts]', '[T, *Ts]', 'C[T, *Ts]'),
('tuple[*Ts]', '[T, *Ts]', 'TypeError'), # Should be tuple[T, *Ts] ('tuple[*Ts]', '[T, *Ts]', 'tuple[T, *Ts]'),
('Tuple[*Ts]', '[T, *Ts]', 'Tuple[T, *Ts]'), ('Tuple[*Ts]', '[T, *Ts]', 'Tuple[T, *Ts]'),
('C[*Ts]', '[*Ts, T]', 'C[*Ts, T]'), ('C[*Ts]', '[*Ts, T]', 'C[*Ts, T]'),
('tuple[*Ts]', '[*Ts, T]', 'TypeError'), # Should be tuple[*Ts, T] ('tuple[*Ts]', '[*Ts, T]', 'tuple[*Ts, T]'),
('Tuple[*Ts]', '[*Ts, T]', 'Tuple[*Ts, T]'), ('Tuple[*Ts]', '[*Ts, T]', 'Tuple[*Ts, T]'),
('C[T, *Ts]', '[int]', 'C[int]'), ('C[T, *Ts]', '[int]', 'C[int]'),
('tuple[T, *Ts]', '[int]', 'TypeError'), # Should be tuple[int] ('tuple[T, *Ts]', '[int]', 'tuple[int]'),
('Tuple[T, *Ts]', '[int]', 'Tuple[int]'), ('Tuple[T, *Ts]', '[int]', 'Tuple[int]'),
('C[T, *Ts]', '[int, str]', 'C[int, str]'), ('C[T, *Ts]', '[int, str]', 'C[int, str]'),
('tuple[T, *Ts]', '[int, str]', 'tuple[int, (str,)]'), # Should be tuple[int, str] ('tuple[T, *Ts]', '[int, str]', 'tuple[int, str]'),
('Tuple[T, *Ts]', '[int, str]', 'Tuple[int, str]'), ('Tuple[T, *Ts]', '[int, str]', 'Tuple[int, str]'),
('C[T, *Ts]', '[int, str, bool]', 'C[int, str, bool]'), ('C[T, *Ts]', '[int, str, bool]', 'C[int, str, bool]'),
('tuple[T, *Ts]', '[int, str, bool]', 'TypeError'), # Should be tuple[int, str, bool] ('tuple[T, *Ts]', '[int, str, bool]', 'tuple[int, str, bool]'),
('Tuple[T, *Ts]', '[int, str, bool]', 'Tuple[int, str, bool]'), ('Tuple[T, *Ts]', '[int, str, bool]', 'Tuple[int, str, bool]'),
('C[T, *Ts]', '[*tuple[int, ...]]', 'C[*tuple[int, ...]]'), # Should be C[int, *tuple[int, ...]] ('C[T, *Ts]', '[*tuple[int, ...]]', 'C[*tuple[int, ...]]'), # Should be C[int, *tuple[int, ...]]
('C[T, *Ts]', '[*Tuple[int, ...]]', 'TypeError'), # Ditto ('C[T, *Ts]', '[*Tuple[int, ...]]', 'TypeError'), # Ditto
('tuple[T, *Ts]', '[*tuple_type[int, ...]]', 'TypeError'), # Should be tuple[int, *tuple[int, ...]] ('tuple[T, *Ts]', '[*tuple[int, ...]]', 'tuple[*tuple[int, ...]]'), # Should be tuple[int, *tuple[int, ...]]
('Tuple[T, *Ts]', '[*tuple[int, ...]]', 'Tuple[*tuple[int, ...]]'), # Ditto ('tuple[T, *Ts]', '[*Tuple[int, ...]]', 'TypeError'), # Should be tuple[int, *Tuple[int, ...]]
('Tuple[T, *Ts]', '[*Tuple[int, ...]]', 'TypeError'), # Ditto ('Tuple[T, *Ts]', '[*tuple[int, ...]]', 'Tuple[*tuple[int, ...]]'), # Should be Tuple[int, *tuple[int, ...]]
('Tuple[T, *Ts]', '[*Tuple[int, ...]]', 'TypeError'), # Should be Tuple[int, *Tuple[int, ...]]
('C[*Ts, T]', '[int]', 'C[int]'), ('C[*Ts, T]', '[int]', 'C[int]'),
('tuple[*Ts, T]', '[int]', 'TypeError'), # Should be tuple[int] ('tuple[*Ts, T]', '[int]', 'tuple[int]'),
('Tuple[*Ts, T]', '[int]', 'Tuple[int]'), ('Tuple[*Ts, T]', '[int]', 'Tuple[int]'),
('C[*Ts, T]', '[int, str]', 'C[int, str]'), ('C[*Ts, T]', '[int, str]', 'C[int, str]'),
('tuple[*Ts, T]', '[int, str]', 'tuple[(int,), str]'), # Should be tuple[int, str] ('tuple[*Ts, T]', '[int, str]', 'tuple[int, str]'),
('Tuple[*Ts, T]', '[int, str]', 'Tuple[int, str]'), ('Tuple[*Ts, T]', '[int, str]', 'Tuple[int, str]'),
('C[*Ts, T]', '[int, str, bool]', 'C[int, str, bool]'), ('C[*Ts, T]', '[int, str, bool]', 'C[int, str, bool]'),
('tuple[*Ts, T]', '[int, str, bool]', 'TypeError'), # Should be tuple[int, str, bool] ('tuple[*Ts, T]', '[int, str, bool]', 'tuple[int, str, bool]'),
('Tuple[*Ts, T]', '[int, str, bool]', 'Tuple[int, str, bool]'), ('Tuple[*Ts, T]', '[int, str, bool]', 'Tuple[int, str, bool]'),
('generic[T, *tuple_type[int, ...]]', '[str]', 'generic[str, *tuple_type[int, ...]]'), ('generic[T, *tuple_type[int, ...]]', '[str]', 'generic[str, *tuple_type[int, ...]]'),
@ -945,7 +945,7 @@ class TypeVarTupleTests(BaseTestCase):
T2 = TypeVar('T2') T2 = TypeVar('T2')
class G(Generic[Unpack[Ts]]): pass class G(Generic[Unpack[Ts]]): pass
for A in G, Tuple: for A in G, Tuple, tuple:
B = A[Unpack[Ts]] B = A[Unpack[Ts]]
self.assertEqual(B[()], A[()]) self.assertEqual(B[()], A[()])
self.assertEqual(B[float], A[float]) self.assertEqual(B[float], A[float])
@ -984,6 +984,21 @@ class TypeVarTupleTests(BaseTestCase):
T2 = TypeVar('T2') T2 = TypeVar('T2')
class G(Generic[Unpack[Ts]]): pass class G(Generic[Unpack[Ts]]): pass
for A in G, Tuple, tuple:
B = A[Ts]
with self.assertRaises(TypeError):
B[int, str]
C = A[T, T2]
with self.assertRaises(TypeError):
C[Unpack[Ts]]
def test_repr_is_correct(self):
Ts = TypeVarTuple('Ts')
T = TypeVar('T')
T2 = TypeVar('T2')
class G(Generic[Unpack[Ts]]): pass
for A in G, Tuple: for A in G, Tuple:
B = A[T, Unpack[Ts], str, T2] B = A[T, Unpack[Ts], str, T2]
with self.assertRaises(TypeError): with self.assertRaises(TypeError):

10
Lib/typing.py
View File

@ -1019,7 +1019,7 @@ class TypeVarTuple(_Final, _Immutable, _PickleUsingNameMixin, _root=True):
return self.__name__ return self.__name__
def __typing_subst__(self, arg): def __typing_subst__(self, arg):
raise AssertionError raise TypeError("Substitution of bare TypeVarTuple is not supported")
class ParamSpecArgs(_Final, _Immutable, _root=True): class ParamSpecArgs(_Final, _Immutable, _root=True):
@ -1686,11 +1686,15 @@ class _UnpackGenericAlias(_GenericAlias, _root=True):
return '*' + repr(self.__args__[0]) return '*' + repr(self.__args__[0])
def __getitem__(self, args): def __getitem__(self, args):
if (len(self.__parameters__) == 1 and if self.__typing_unpacked__():
isinstance(self.__parameters__[0], TypeVarTuple)):
return args return args
return super().__getitem__(args) return super().__getitem__(args)
def __typing_unpacked__(self):
# If x is Unpack[tuple[...]], __parameters__ will be empty.
return bool(self.__parameters__ and
isinstance(self.__parameters__[0], TypeVarTuple))
class Generic: class Generic:
"""Abstract base class for generic types. """Abstract base class for generic types.

118
Objects/genericaliasobject.c
View File

@ -190,6 +190,23 @@ tuple_add(PyObject *self, Py_ssize_t len, PyObject *item)
return 0; return 0;
} }
static Py_ssize_t
tuple_extend(PyObject **dst, Py_ssize_t dstindex,
PyObject **src, Py_ssize_t count)
{
assert(count >= 0);
if (_PyTuple_Resize(dst, PyTuple_GET_SIZE(*dst) + count - 1) != 0) {
return -1;
}
assert(dstindex + count <= PyTuple_GET_SIZE(*dst));
for (Py_ssize_t i = 0; i < count; ++i) {
PyObject *item = src[i];
Py_INCREF(item);
PyTuple_SET_ITEM(*dst, dstindex + i, item);
}
return dstindex + count;
}
PyObject * PyObject *
_Py_make_parameters(PyObject *args) _Py_make_parameters(PyObject *args)
{ {
@ -251,7 +268,8 @@ _Py_make_parameters(PyObject *args)
If obj doesn't have a __parameters__ attribute or that's not If obj doesn't have a __parameters__ attribute or that's not
a non-empty tuple, return a new reference to obj. */ a non-empty tuple, return a new reference to obj. */
static PyObject * static PyObject *
subs_tvars(PyObject *obj, PyObject *params, PyObject **argitems) subs_tvars(PyObject *obj, PyObject *params,
PyObject **argitems, Py_ssize_t nargs, Py_ssize_t varparam)
{ {
PyObject *subparams; PyObject *subparams;
if (_PyObject_LookupAttr(obj, &_Py_ID(__parameters__), &subparams) < 0) { if (_PyObject_LookupAttr(obj, &_Py_ID(__parameters__), &subparams) < 0) {
@ -265,14 +283,27 @@ subs_tvars(PyObject *obj, PyObject *params, PyObject **argitems)
Py_DECREF(subparams); Py_DECREF(subparams);
return NULL; return NULL;
} }
for (Py_ssize_t i = 0; i < nsubargs; ++i) { for (Py_ssize_t i = 0, j = 0; i < nsubargs; ++i) {
PyObject *arg = PyTuple_GET_ITEM(subparams, i); PyObject *arg = PyTuple_GET_ITEM(subparams, i);
Py_ssize_t iparam = tuple_index(params, nparams, arg); Py_ssize_t iparam = tuple_index(params, nparams, arg);
if (iparam >= 0) { if (iparam == varparam) {
arg = argitems[iparam]; j = tuple_extend(&subargs, j,
argitems + iparam, nargs - nparams + 1);
if (j < 0) {
return NULL;
}
}
else {
if (iparam >= 0) {
if (iparam > varparam) {
iparam += nargs - nsubargs;
}
arg = argitems[iparam];
}
Py_INCREF(arg);
PyTuple_SET_ITEM(subargs, j, arg);
j++;
} }
Py_INCREF(arg);
PyTuple_SET_ITEM(subargs, i, arg);
} }
obj = PyObject_GetItem(obj, subargs); obj = PyObject_GetItem(obj, subargs);
@ -286,6 +317,23 @@ subs_tvars(PyObject *obj, PyObject *params, PyObject **argitems)
return obj; return obj;
} }
static int
_is_unpacked_typevartuple(PyObject *arg)
{
PyObject *meth;
int res = _PyObject_LookupAttr(arg, &_Py_ID(__typing_unpacked__), &meth);
if (res > 0) {
PyObject *tmp = PyObject_CallNoArgs(meth);
Py_DECREF(meth);
if (tmp == NULL) {
return -1;
}
res = PyObject_IsTrue(tmp);
Py_DECREF(tmp);
}
return res;
}
PyObject * PyObject *
_Py_subs_parameters(PyObject *self, PyObject *args, PyObject *parameters, PyObject *item) _Py_subs_parameters(PyObject *self, PyObject *args, PyObject *parameters, PyObject *item)
{ {
@ -298,11 +346,27 @@ _Py_subs_parameters(PyObject *self, PyObject *args, PyObject *parameters, PyObje
int is_tuple = PyTuple_Check(item); int is_tuple = PyTuple_Check(item);
Py_ssize_t nitems = is_tuple ? PyTuple_GET_SIZE(item) : 1; Py_ssize_t nitems = is_tuple ? PyTuple_GET_SIZE(item) : 1;
PyObject **argitems = is_tuple ? &PyTuple_GET_ITEM(item, 0) : &item; PyObject **argitems = is_tuple ? &PyTuple_GET_ITEM(item, 0) : &item;
if (nitems != nparams) { Py_ssize_t varparam = 0;
return PyErr_Format(PyExc_TypeError, for (; varparam < nparams; varparam++) {
"Too %s arguments for %R", PyObject *param = PyTuple_GET_ITEM(parameters, varparam);
nitems > nparams ? "many" : "few", if (Py_TYPE(param)->tp_iter) { // TypeVarTuple
self); break;
}
}
if (varparam < nparams) {
if (nitems < nparams - 1) {
return PyErr_Format(PyExc_TypeError,
"Too few arguments for %R",
self);
}
}
else {
if (nitems != nparams) {
return PyErr_Format(PyExc_TypeError,
"Too %s arguments for %R",
nitems > nparams ? "many" : "few",
self);
}
} }
/* Replace all type variables (specified by parameters) /* Replace all type variables (specified by parameters)
with corresponding values specified by argitems. with corresponding values specified by argitems.
@ -315,8 +379,13 @@ _Py_subs_parameters(PyObject *self, PyObject *args, PyObject *parameters, PyObje
if (newargs == NULL) { if (newargs == NULL) {
return NULL; return NULL;
} }
for (Py_ssize_t iarg = 0; iarg < nargs; iarg++) { for (Py_ssize_t iarg = 0, jarg = 0; iarg < nargs; iarg++) {
PyObject *arg = PyTuple_GET_ITEM(args, iarg); PyObject *arg = PyTuple_GET_ITEM(args, iarg);
int unpack = _is_unpacked_typevartuple(arg);
if (unpack < 0) {
Py_DECREF(newargs);
return NULL;
}
PyObject *subst; PyObject *subst;
if (_PyObject_LookupAttr(arg, &_Py_ID(__typing_subst__), &subst) < 0) { if (_PyObject_LookupAttr(arg, &_Py_ID(__typing_subst__), &subst) < 0) {
Py_DECREF(newargs); Py_DECREF(newargs);
@ -325,17 +394,38 @@ _Py_subs_parameters(PyObject *self, PyObject *args, PyObject *parameters, PyObje
if (subst) { if (subst) {
Py_ssize_t iparam = tuple_index(parameters, nparams, arg); Py_ssize_t iparam = tuple_index(parameters, nparams, arg);
assert(iparam >= 0); assert(iparam >= 0);
if (iparam == varparam) {
Py_DECREF(subst);
Py_DECREF(newargs);
PyErr_SetString(PyExc_TypeError,
"Substitution of bare TypeVarTuple is not supported");
return NULL;
}
if (iparam > varparam) {
iparam += nitems - nparams;
}
arg = PyObject_CallOneArg(subst, argitems[iparam]); arg = PyObject_CallOneArg(subst, argitems[iparam]);
Py_DECREF(subst); Py_DECREF(subst);
} }
else { else {
arg = subs_tvars(arg, parameters, argitems); arg = subs_tvars(arg, parameters, argitems, nitems, varparam);
} }
if (arg == NULL) { if (arg == NULL) {
Py_DECREF(newargs); Py_DECREF(newargs);
return NULL; return NULL;
} }
PyTuple_SET_ITEM(newargs, iarg, arg); if (unpack) {
jarg = tuple_extend(&newargs, jarg,
&PyTuple_GET_ITEM(arg, 0), PyTuple_GET_SIZE(arg));
Py_DECREF(arg);
if (jarg < 0) {
return NULL;
}
}
else {
PyTuple_SET_ITEM(newargs, jarg, arg);
jarg++;
}
} }
return newargs; return newargs;