bpo-44731: Simplify the union type implementation (GH-27318) (GH-27334)
Remove direct support of typing types in the C code because they are already supported by defining methods __or__ and __ror__ in the Python code.
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
diff --git a/Objects/unionobject.c b/Objects/unionobject.c
index 54cdeda..9804d87 100644
--- a/Objects/unionobject.c
+++ b/Objects/unionobject.c
@@ -115,31 +115,6 @@ union_subclasscheck(PyObject *self, PyObject *instance)
Py_RETURN_FALSE;
}
-static int
-is_typing_module(PyObject *obj)
-{
- _Py_IDENTIFIER(__module__);
- PyObject *module;
- if (_PyObject_LookupAttrId(obj, &PyId___module__, &module) < 0) {
- return -1;
- }
- int is_typing = (module != NULL &&
- PyUnicode_Check(module) &&
- _PyUnicode_EqualToASCIIString(module, "typing"));
- Py_XDECREF(module);
- return is_typing;
-}
-
-static int
-is_typing_name(PyObject *obj, const char *name)
-{
- PyTypeObject *type = Py_TYPE(obj);
- if (strcmp(type->tp_name, name) != 0) {
- return 0;
- }
- return is_typing_module((PyObject *)type);
-}
-
static PyObject *
union_richcompare(PyObject *a, PyObject *b, int op)
{
@@ -252,51 +227,12 @@ dedup_and_flatten_args(PyObject* args)
}
static int
-is_typevar(PyObject *obj)
-{
- return is_typing_name(obj, "TypeVar");
-}
-
-static int
-is_special_form(PyObject *obj)
-{
- return is_typing_name(obj, "_SpecialForm");
-}
-
-static int
-is_new_type(PyObject *obj)
-{
- PyTypeObject *type = Py_TYPE(obj);
- if (type != &PyFunction_Type) {
- return 0;
- }
- return is_typing_module(obj);
-}
-
-// Emulates short-circuiting behavior of the ``||`` operator
-// while also checking negative values.
-#define CHECK_RES(res) { \
- int result = res; \
- if (result) { \
- return result; \
- } \
-}
-
-// Returns 1 on true, 0 on false, and -1 on error.
-static int
is_unionable(PyObject *obj)
{
- if (obj == Py_None ||
+ return (obj == Py_None ||
PyType_Check(obj) ||
_PyGenericAlias_Check(obj) ||
- _PyUnion_Check(obj))
- {
- return 1;
- }
- CHECK_RES(is_typevar(obj));
- CHECK_RES(is_new_type(obj));
- CHECK_RES(is_special_form(obj));
- return 0;
+ _PyUnion_Check(obj));
}
static int
@@ -305,12 +241,9 @@ is_args_unionable(PyObject *args)
Py_ssize_t nargs = PyTuple_GET_SIZE(args);
for (Py_ssize_t iarg = 0; iarg < nargs; iarg++) {
PyObject *arg = PyTuple_GET_ITEM(args, iarg);
- int is_arg_unionable = is_unionable(arg);
- if (is_arg_unionable <= 0) {
- if (is_arg_unionable == 0) {
- PyErr_Format(PyExc_TypeError,
- "Each union argument must be a type, got %.100R", arg);
- }
+ if (!is_unionable(arg)) {
+ PyErr_Format(PyExc_TypeError,
+ "Each union argument must be a type, got %.100R", arg);
return 0;
}
}
@@ -320,14 +253,7 @@ is_args_unionable(PyObject *args)
PyObject *
_Py_union_type_or(PyObject* self, PyObject* other)
{
- int r = is_unionable(self);
- if (r > 0) {
- r = is_unionable(other);
- }
- if (r < 0) {
- return NULL;
- }
- if (!r) {
+ if (!is_unionable(self) || !is_unionable(other)) {
Py_RETURN_NOTIMPLEMENTED;
}
@@ -465,7 +391,7 @@ union_from_args(PyObject *cls, PyObject *args)
return NULL;
}
- if (is_args_unionable(args) <= 0) {
+ if (!is_args_unionable(args)) {
return NULL;
}