GH-103899: Provide a hint when accidentally calling a module (GH-103900)

Lib/test/test_call.py

@@ -10,6 +10,7 @@
 import gc
 import contextlib
 import sys
+import types
 
 
 class BadStr(str):
@@ -202,6 +203,37 @@ def test_oldargs1_2_kw(self):
  msg = r"count\(\) takes no keyword arguments"
  self.assertRaisesRegex(TypeError, msg, [].count, x=2, y=2)
 
+ def test_object_not_callable(self):
+ msg = r"^'object' object is not callable$"
+ self.assertRaisesRegex(TypeError, msg, object())
+
+ def test_module_not_callable_no_suggestion_0(self):
+ msg = r"^'module' object is not callable$"
+ self.assertRaisesRegex(TypeError, msg, types.ModuleType("mod"))
+
+ def test_module_not_callable_no_suggestion_1(self):
+ msg = r"^'module' object is not callable$"
+ mod = types.ModuleType("mod")
+ mod.mod = 42
+ self.assertRaisesRegex(TypeError, msg, mod)
+
+ def test_module_not_callable_no_suggestion_2(self):
+ msg = r"^'module' object is not callable$"
+ mod = types.ModuleType("mod")
+ del mod.__name__
+ self.assertRaisesRegex(TypeError, msg, mod)
+
+ def test_module_not_callable_no_suggestion_3(self):
+ msg = r"^'module' object is not callable$"
+ mod = types.ModuleType("mod")
+ mod.__name__ = 42
+ self.assertRaisesRegex(TypeError, msg, mod)
+
+ def test_module_not_callable_suggestion(self):
+ msg = r"^'module' object is not callable\. Did you mean: 'mod\.mod\(\.\.\.\)'\?$"
+ mod = types.ModuleType("mod")
+ mod.mod = lambda: ...
+ self.assertRaisesRegex(TypeError, msg, mod)
 
 
 class TestCallingConventions(unittest.TestCase):

Misc/NEWS.d/next/Core and Builtins/2023-04-26-15-14-23.gh-issue-103899.1pqKPF.rst

@@ -0,0 +1,3 @@
+Provide a helpful hint in the :exc:`TypeError` message when accidentally
+calling a :term:`module` object that has a callable attribute of the same
+name (such as :func:`dis.dis` or :class:`datetime.datetime`).

Objects/call.c

@@ -157,6 +157,42 @@ PyObject_VectorcallDict(PyObject *callable, PyObject *const *args,
  return _PyObject_FastCallDictTstate(tstate, callable, args, nargsf, kwargs);
 }
 
+static void
+object_is_not_callable(PyThreadState *tstate, PyObject *callable)
+{
+ if (Py_IS_TYPE(callable, &PyModule_Type)) {
+ // >>> import pprint
+ // >>> pprint(thing)
+ // Traceback (most recent call last):
+ // File "<stdin>", line 1, in <module>
+ // TypeError: 'module' object is not callable. Did you mean: 'pprint.pprint(...)'?
+ PyObject *name = PyModule_GetNameObject(callable);
+ if (name == NULL) {
+ _PyErr_Clear(tstate);
+ goto basic_type_error;
+ }
+ PyObject *attr;
+ int res = _PyObject_LookupAttr(callable, name, &attr);
+ if (res < 0) {
+ _PyErr_Clear(tstate);
+ }
+ else if (res > 0 && PyCallable_Check(attr)) {
+ _PyErr_Format(tstate, PyExc_TypeError,
+ "'%.200s' object is not callable. "
+ "Did you mean: '%U.%U(...)'?",
+ Py_TYPE(callable)->tp_name, name, name);
+ Py_DECREF(attr);
+ Py_DECREF(name);
+ return;
+ }
+ Py_XDECREF(attr);
+ Py_DECREF(name);
+ }
+basic_type_error:
+ _PyErr_Format(tstate, PyExc_TypeError, "'%.200s' object is not callable",
+ Py_TYPE(callable)->tp_name);
+}
+
 
 PyObject *
 _PyObject_MakeTpCall(PyThreadState *tstate, PyObject *callable,
@@ -171,9 +207,7 @@ _PyObject_MakeTpCall(PyThreadState *tstate, PyObject *callable,
  * temporary dictionary for keyword arguments (if any) */
  ternaryfunc call = Py_TYPE(callable)->tp_call;
  if (call == NULL) {
- _PyErr_Format(tstate, PyExc_TypeError,
- "'%.200s' object is not callable",
- Py_TYPE(callable)->tp_name);
+ object_is_not_callable(tstate, callable);
  return NULL;
  }
 
@@ -322,9 +356,7 @@ _PyObject_Call(PyThreadState *tstate, PyObject *callable,
  else {
  call = Py_TYPE(callable)->tp_call;
  if (call == NULL) {
- _PyErr_Format(tstate, PyExc_TypeError,
- "'%.200s' object is not callable",
- Py_TYPE(callable)->tp_name);
+ object_is_not_callable(tstate, callable);
  return NULL;
  }