Trigger events when {kw}defaults are changed via the C-API

python · erlend-aasland · Nov 22, 2022 · Sep 23, 2022 · Nov 8, 2022 · Nov 8, 2022
commit 0fdc7d774861f7dc51bb954ec80f5c0081b9aa29
diff --git a/Lib/test/test_capi.py b/Lib/test/test_capi.py
@@ -46,6 +46,8 @@
     _add_func_watcher,
     _allocate_too_many_func_watchers,
     _clear_func_watcher,
+    _set_func_defaults_via_capi,
+    _set_func_kwdefaults_via_capi,
 )
 
 import _testinternalcapi
@@ -1595,10 +1597,18 @@ def myfunc():
             myfunc.__defaults__ = new_defaults
             self.assertIn((PYFUNC_EVENT_MODIFY_DEFAULTS, myfunc, new_defaults), events)
 
+            new_defaults = (456,)
+            _set_func_defaults_via_capi(myfunc, new_defaults)
+            self.assertIn((PYFUNC_EVENT_MODIFY_DEFAULTS, myfunc, new_defaults), events)
+
             new_kwdefaults = {"self": 123}
             myfunc.__kwdefaults__ = new_kwdefaults
             self.assertIn((PYFUNC_EVENT_MODIFY_KWDEFAULTS, myfunc, new_kwdefaults), events)
 
+            new_kwdefaults = {"self": 456}
+            _set_func_kwdefaults_via_capi(myfunc, new_kwdefaults)
+            self.assertIn((PYFUNC_EVENT_MODIFY_KWDEFAULTS, myfunc, new_kwdefaults), events)
+
             # Clear events reference to func
             events = []
             del myfunc

diff --git a/Modules/_testcapi/func_events.c b/Modules/_testcapi/func_events.c
@@ -190,10 +190,40 @@ allocate_too_many_watchers(PyObject *self, PyObject *args)
     Py_RETURN_NONE;
 }
 
+static PyObject *
+set_defaults(PyObject *self, PyObject *args)
+{
+    PyObject *func = NULL;
+    PyObject *defaults = NULL;
+    if (!PyArg_ParseTuple(args, "OO", &func, &defaults)) {
+        return NULL;
+    }
+    if (PyFunction_SetDefaults(func, defaults) < 0) {
+        return NULL;
+    }
+    Py_RETURN_NONE;
+}
+
+static PyObject *
+set_kwdefaults(PyObject *self, PyObject *args)
+{
+    PyObject *func = NULL;
+    PyObject *kwdefaults = NULL;
+    if (!PyArg_ParseTuple(args, "OO", &func, &kwdefaults)) {
+        return NULL;
+    }
+    if (PyFunction_SetKwDefaults(func, kwdefaults) < 0) {
+        return NULL;
+    }
+    Py_RETURN_NONE;
+}
+
 static PyMethodDef TestMethods[] = {
     {"_add_func_watcher", add_watcher, METH_O},
     {"_clear_func_watcher", clear_watcher, METH_O},
     {"_allocate_too_many_func_watchers", allocate_too_many_watchers, METH_NOARGS},
+    {"_set_func_defaults_via_capi", set_defaults, METH_VARARGS},
+    {"_set_func_kwdefaults_via_capi", set_kwdefaults, METH_VARARGS},
     {NULL},
 };
 

diff --git a/Objects/funcobject.c b/Objects/funcobject.c
@@ -255,7 +255,8 @@ PyFunction_SetDefaults(PyObject *op, PyObject *defaults)
         PyErr_SetString(PyExc_SystemError, "non-tuple default args");
         return -1;
     }
-    handle_func_event(PyFunction_EVENT_MODIFY_DEFAULTS, op, NULL);
+    handle_func_event(PyFunction_EVENT_MODIFY_DEFAULTS,
+                      (PyFunctionObject *) op, defaults);
     ((PyFunctionObject *)op)->func_version = 0;
     Py_XSETREF(((PyFunctionObject *)op)->func_defaults, defaults);
     return 0;
@@ -296,7 +297,8 @@ PyFunction_SetKwDefaults(PyObject *op, PyObject *defaults)
                         "non-dict keyword only default args");
         return -1;
     }
-    handle_func_event(PyFunction_EVENT_MODIFY_KWDEFAULTS, op, NULL);
+    handle_func_event(PyFunction_EVENT_MODIFY_KWDEFAULTS,
+                      (PyFunctionObject *) op, defaults);
     ((PyFunctionObject *)op)->func_version = 0;
     Py_XSETREF(((PyFunctionObject *)op)->func_kwdefaults, defaults);
     return 0;