gh-155952: Fix <unrepresentable> Argument Clinic defaults in several signatures

Lib/test/test_inspect/test_inspect.py

@@ -6411,7 +6411,7 @@ def test_typing_module_has_signatures(self):
                 methods_unsupported_signature=methods_unsupported_signature)
 
     def test_warnings_module_has_signatures(self):
-        unsupported_signature = {'warn', 'warn_explicit'}
+        unsupported_signature = {'warn_explicit'}
         self._test_module_has_signatures(warnings, unsupported_signature=unsupported_signature)
 
     def test_weakref_module_has_signatures(self):

Misc/NEWS.d/next/Library/2026-08-17-12-40-00.gh-issue-155952.Vq3Lm8.rst

@@ -0,0 +1,3 @@
+Fix the signatures of :meth:`sqlite3.Connection.execute`, :func:`warnings.warn`
+and :func:`locale.setlocale` which rendered ``<unrepresentable>`` instead of the
+correct defaults for parameters.

Modules/_localemodule.c

@@ -126,15 +126,15 @@ check_locale_name_all(const char *locale)
 _locale.setlocale
 
     category: int
-    locale: str(accept={str, NoneType}) = NULL
+    locale: str(accept={str, NoneType}) = None
     /
 
 Activates/queries locale processing.
 [clinic start generated code]*/
 
 static PyObject *
 _locale_setlocale_impl(PyObject *module, int category, const char *locale)
-/*[clinic end generated code: output=a0e777ae5d2ff117 input=dbe18f1d66c57a6a]*/
+/*[clinic end generated code: output=a0e777ae5d2ff117 input=b53449b63407179b]*/
 {
     char *result;
     PyObject *result_object;

Modules/_sqlite/connection.c

@@ -1872,7 +1872,7 @@ pysqlite_connection_call(PyObject *op, PyObject *args, PyObject *kwargs)
 _sqlite3.Connection.execute as pysqlite_connection_execute
 
     sql: unicode
-    parameters: object = NULL
+    parameters: object(c_default = 'NULL') = ()
     /
 
 Executes an SQL statement.
@@ -1881,7 +1881,7 @@ Executes an SQL statement.
 static PyObject *
 pysqlite_connection_execute_impl(pysqlite_Connection *self, PyObject *sql,
                                  PyObject *parameters)
-/*[clinic end generated code: output=5be05ae01ee17ee4 input=27aa7792681ddba2]*/
+/*[clinic end generated code: output=5be05ae01ee17ee4 input=847390a17de45cc7]*/
 {
     PyObject* result = 0;
 

Objects/typevarobject.c

@@ -2145,7 +2145,7 @@ typealias.__new__ as typealias_new
     name: object(subclass_of="&PyUnicode_Type")
     value: object
     *
-    type_params: object = NULL
+    type_params: object(c_default="NULL") = ()
     qualname: object(c_default="NULL") = None
 
 Create a TypeAliasType.
@@ -2154,7 +2154,7 @@ Create a TypeAliasType.
 static PyObject *
 typealias_new_impl(PyTypeObject *type, PyObject *name, PyObject *value,
                    PyObject *type_params, PyObject *qualname)
-/*[clinic end generated code: output=b7f6d9f1c577cd9c input=cbec290f8c4886ef]*/
+/*[clinic end generated code: output=b7f6d9f1c577cd9c input=6516623275f87b5e]*/
 {
     if (type_params != NULL && !PyTuple_Check(type_params)) {
         PyErr_SetString(PyExc_TypeError, "type_params must be a tuple");

Python/_warnings.c

@@ -1156,7 +1156,7 @@ warn as warnings_warn
     source: object = None
       If supplied, the destroyed object which emitted a ResourceWarning
     *
-    skip_file_prefixes: object(type='PyTupleObject *', subclass_of='&PyTuple_Type') = NULL
+    skip_file_prefixes: object(type='PyTupleObject *', subclass_of='&PyTuple_Type', c_default='NULL') = ()
       An optional tuple of module filename prefixes indicating frames to skip
       during stacklevel computations for stack frame attribution.
 
@@ -1167,7 +1167,7 @@ static PyObject *
 warnings_warn_impl(PyObject *module, PyObject *message, PyObject *category,
                    Py_ssize_t stacklevel, PyObject *source,
                    PyTupleObject *skip_file_prefixes)
-/*[clinic end generated code: output=a68e0f6906c65f80 input=eb37c6a18bec4ea1]*/
+/*[clinic end generated code: output=a68e0f6906c65f80 input=2b52e8b20f508f51]*/
 {
     category = get_category(message, category);
     if (category == NULL)