bpo-43682: @staticmethod inherits attributes (GH-25268)
Static methods (@staticmethod) and class methods (@classmethod) now
inherit the method attributes (__module__, __name__, __qualname__,
__doc__, __annotations__) and have a new __wrapped__ attribute.
Changes:
* Add a repr() method to staticmethod and classmethod types.
* Add tests on the @classmethod decorator.
diff --git a/Objects/funcobject.c b/Objects/funcobject.c
index 45135a8..df59131 100644
--- a/Objects/funcobject.c
+++ b/Objects/funcobject.c
@@ -639,7 +639,7 @@ static PyObject*
func_repr(PyFunctionObject *op)
{
return PyUnicode_FromFormat("<function %U at %p>",
- op->func_qualname, op);
+ op->func_qualname, op);
}
static int
@@ -715,6 +715,50 @@ PyTypeObject PyFunction_Type = {
};
+static int
+functools_copy_attr(PyObject *wrapper, PyObject *wrapped, PyObject *name)
+{
+ PyObject *value = PyObject_GetAttr(wrapped, name);
+ if (value == NULL) {
+ if (PyErr_ExceptionMatches(PyExc_AttributeError)) {
+ PyErr_Clear();
+ return 0;
+ }
+ return -1;
+ }
+
+ int res = PyObject_SetAttr(wrapper, name, value);
+ Py_DECREF(value);
+ return res;
+}
+
+// Similar to functools.wraps(wrapper, wrapped)
+static int
+functools_wraps(PyObject *wrapper, PyObject *wrapped)
+{
+#define COPY_ATTR(ATTR) \
+ do { \
+ _Py_IDENTIFIER(ATTR); \
+ PyObject *attr = _PyUnicode_FromId(&PyId_ ## ATTR); \
+ if (attr == NULL) { \
+ return -1; \
+ } \
+ if (functools_copy_attr(wrapper, wrapped, attr) < 0) { \
+ return -1; \
+ } \
+ } while (0) \
+
+ COPY_ATTR(__module__);
+ COPY_ATTR(__name__);
+ COPY_ATTR(__qualname__);
+ COPY_ATTR(__doc__);
+ COPY_ATTR(__annotations__);
+ return 0;
+
+#undef COPY_ATTR
+}
+
+
/* Class method object */
/* A class method receives the class as implicit first argument,
@@ -798,11 +842,16 @@ cm_init(PyObject *self, PyObject *args, PyObject *kwds)
return -1;
Py_INCREF(callable);
Py_XSETREF(cm->cm_callable, callable);
+
+ if (functools_wraps((PyObject *)cm, cm->cm_callable) < 0) {
+ return -1;
+ }
return 0;
}
static PyMemberDef cm_memberlist[] = {
{"__func__", T_OBJECT, offsetof(classmethod, cm_callable), READONLY},
+ {"__wrapped__", T_OBJECT, offsetof(classmethod, cm_callable), READONLY},
{NULL} /* Sentinel */
};
@@ -821,13 +870,17 @@ cm_get___isabstractmethod__(classmethod *cm, void *closure)
static PyGetSetDef cm_getsetlist[] = {
{"__isabstractmethod__",
- (getter)cm_get___isabstractmethod__, NULL,
- NULL,
- NULL},
+ (getter)cm_get___isabstractmethod__, NULL, NULL, NULL},
{"__dict__", PyObject_GenericGetDict, PyObject_GenericSetDict, NULL, NULL},
{NULL} /* Sentinel */
};
+static PyObject*
+cm_repr(classmethod *cm)
+{
+ return PyUnicode_FromFormat("<classmethod(%R)>", cm->cm_callable);
+}
+
PyDoc_STRVAR(classmethod_doc,
"classmethod(function) -> method\n\
\n\
@@ -860,7 +913,7 @@ PyTypeObject PyClassMethod_Type = {
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_as_async */
- 0, /* tp_repr */
+ (reprfunc)cm_repr, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
@@ -980,11 +1033,16 @@ sm_init(PyObject *self, PyObject *args, PyObject *kwds)
return -1;
Py_INCREF(callable);
Py_XSETREF(sm->sm_callable, callable);
+
+ if (functools_wraps((PyObject *)sm, sm->sm_callable) < 0) {
+ return -1;
+ }
return 0;
}
static PyMemberDef sm_memberlist[] = {
{"__func__", T_OBJECT, offsetof(staticmethod, sm_callable), READONLY},
+ {"__wrapped__", T_OBJECT, offsetof(staticmethod, sm_callable), READONLY},
{NULL} /* Sentinel */
};
@@ -1003,13 +1061,17 @@ sm_get___isabstractmethod__(staticmethod *sm, void *closure)
static PyGetSetDef sm_getsetlist[] = {
{"__isabstractmethod__",
- (getter)sm_get___isabstractmethod__, NULL,
- NULL,
- NULL},
+ (getter)sm_get___isabstractmethod__, NULL, NULL, NULL},
{"__dict__", PyObject_GenericGetDict, PyObject_GenericSetDict, NULL, NULL},
{NULL} /* Sentinel */
};
+static PyObject*
+sm_repr(staticmethod *sm)
+{
+ return PyUnicode_FromFormat("<staticmethod(%R)>", sm->sm_callable);
+}
+
PyDoc_STRVAR(staticmethod_doc,
"staticmethod(function) -> method\n\
\n\
@@ -1040,7 +1102,7 @@ PyTypeObject PyStaticMethod_Type = {
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_as_async */
- 0, /* tp_repr */
+ (reprfunc)sm_repr, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */