Account for kwdefaults when copying function

Author: lkubb

changelog/69901.fixed.md

@@ -0,0 +1 @@
+Fixed `salt.utils.functools` `namespaced_function`/`alias_function` dropping keyword-only argument defaults in copied function

salt/utils/functools.py

@@ -61,6 +61,9 @@ def namespaced_function(function, global_dict, defaults=None, preserve_context=N
         closure=function.__closure__,
     )
     new_namespaced_function.__dict__.update(function.__dict__)
+    if function.__kwdefaults__ is not None:
+        # Only Py 3.13+ accept this in FunctionType.__new__
+        new_namespaced_function.__kwdefaults__ = function.__kwdefaults__.copy()
     return new_namespaced_function
 
 
@@ -76,6 +79,9 @@ def alias_function(fun, name, doc=None):
         fun.__closure__,
     )
     alias_fun.__dict__.update(fun.__dict__)
+    if fun.__kwdefaults__ is not None:
+        # Only Py 3.13+ accept this in FunctionType.__new__
+        alias_fun.__kwdefaults__ = fun.__kwdefaults__.copy()
 
     if doc and isinstance(doc, str):
         alias_fun.__doc__ = doc

tests/pytests/functional/utils/functools/test_alias_function.py

@@ -8,4 +8,4 @@ def func(_arg, *, default="foo"):
     func2 = alias_function(func, "func2")
 
     assert func(None) == "foo"
-    assert func2(None) == "foo"
+    assert func2(None) == "foo"  # pylint: disable=not-callable

tests/pytests/functional/utils/functools/test_namespaced_function.py

@@ -63,18 +63,14 @@ def main():
     import foopkg.mod1
 
     foopkg.mod1.main()
-    """.format(
-        CODE_DIR
-    )
+    """.format(CODE_DIR)
     run2_contents = """
     import sys
     sys.path.insert(0, '{}')
     import foopkg.mod2
 
     foopkg.mod2.main()
-    """.format(
-        CODE_DIR
-    )
+    """.format(CODE_DIR)
     with pytest.helpers.temp_file(
         "run1.py", contents=run1_contents, directory=tmp_path
     ), pytest.helpers.temp_file(
@@ -83,9 +79,7 @@ def main():
         "__init__.py", contents="", directory=pkgpath
     ), pytest.helpers.temp_file(
         "mod1.py", mod1_contents, directory=pkgpath
-    ), pytest.helpers.temp_file(
-        "mod2.py", mod2_contents, directory=pkgpath
-    ):
+    ), pytest.helpers.temp_file("mod2.py", mod2_contents, directory=pkgpath):
         ret = shell.run(sys.executable, str(tmp_path / "run1.py"), cwd=str(tmp_path))
         log.warning(ret)
         assert ret.returncode == 0
@@ -139,4 +133,4 @@ def func(_arg, *, default="foo"):
     func2 = namespaced_function(func, globals())
 
     assert func(None) == "foo"
-    assert func2(None) == "foo"
+    assert func2(None) == "foo"  # pylint: disable=not-callable