pythongh-118473: Fix set_asyncgen_hooks not to be partially set when …

…arguments are invalid (python#118474)

Lib/test/test_sys.py

@@ -1788,14 +1788,28 @@ def test_asyncgen_hooks(self):
  self.assertIsNone(old.finalizer)
 
  firstiter = lambda *a: None
+ finalizer = lambda *a: None
+
+ with self.assertRaises(TypeError):
+ sys.set_asyncgen_hooks(firstiter=firstiter, finalizer="invalid")
+ cur = sys.get_asyncgen_hooks()
+ self.assertIsNone(cur.firstiter)
+ self.assertIsNone(cur.finalizer)
+
+ # gh-118473
+ with self.assertRaises(TypeError):
+ sys.set_asyncgen_hooks(firstiter="invalid", finalizer=finalizer)
+ cur = sys.get_asyncgen_hooks()
+ self.assertIsNone(cur.firstiter)
+ self.assertIsNone(cur.finalizer)
+
  sys.set_asyncgen_hooks(firstiter=firstiter)
  hooks = sys.get_asyncgen_hooks()
  self.assertIs(hooks.firstiter, firstiter)
  self.assertIs(hooks[0], firstiter)
  self.assertIs(hooks.finalizer, None)
  self.assertIs(hooks[1], None)
 
- finalizer = lambda *a: None
  sys.set_asyncgen_hooks(finalizer=finalizer)
  hooks = sys.get_asyncgen_hooks()
  self.assertIs(hooks.firstiter, firstiter)

Misc/NEWS.d/next/Core and Builtins/2024-05-01-22-43-54.gh-issue-118473.QIvq9R.rst

@@ -0,0 +1 @@
+Fix :func:`sys.set_asyncgen_hooks` not to be partially set when raising :exc:`TypeError`.

Python/sysmodule.c

@@ -1399,12 +1399,6 @@ sys_set_asyncgen_hooks(PyObject *self, PyObject *args, PyObject *kw)
  Py_TYPE(finalizer)->tp_name);
  return NULL;
  }
- if (_PyEval_SetAsyncGenFinalizer(finalizer) < 0) {
- return NULL;
- }
- }
- else if (finalizer == Py_None && _PyEval_SetAsyncGenFinalizer(NULL) < 0) {
- return NULL;
  }
 
  if (firstiter && firstiter != Py_None) {
@@ -1414,15 +1408,33 @@ sys_set_asyncgen_hooks(PyObject *self, PyObject *args, PyObject *kw)
  Py_TYPE(firstiter)->tp_name);
  return NULL;
  }
- if (_PyEval_SetAsyncGenFirstiter(firstiter) < 0) {
+ }
+
+ PyObject *cur_finalizer = _PyEval_GetAsyncGenFinalizer();
+
+ if (finalizer && finalizer != Py_None) {
+ if (_PyEval_SetAsyncGenFinalizer(finalizer) < 0) {
  return NULL;
  }
  }
- else if (firstiter == Py_None && _PyEval_SetAsyncGenFirstiter(NULL) < 0) {
+ else if (finalizer == Py_None && _PyEval_SetAsyncGenFinalizer(NULL) < 0) {
  return NULL;
  }
 
+ if (firstiter && firstiter != Py_None) {
+ if (_PyEval_SetAsyncGenFirstiter(firstiter) < 0) {
+ goto error;
+ }
+ }
+ else if (firstiter == Py_None && _PyEval_SetAsyncGenFirstiter(NULL) < 0) {
+ goto error;
+ }
+
  Py_RETURN_NONE;
+
+error:
+ _PyEval_SetAsyncGenFinalizer(cur_finalizer);
+ return NULL;
 }
 
 PyDoc_STRVAR(set_asyncgen_hooks_doc,