stubgen: fix non default keyword-only argument positioning (#12303)

Fixes #11082

Author: shoracek

mypy/stubgen.py

@@ -649,9 +649,11 @@ def visit_func_def(self, o: FuncDef, is_abstract: bool = False,
                 # type "UnboundType" and will not match.
                 if not isinstance(get_proper_type(annotated_type), AnyType):
                     annotation = ": {}".format(self.print_annotation(annotated_type))
+
+            if kind.is_named() and not any(arg.startswith('*') for arg in args):
+                args.append('*')
+
             if arg_.initializer:
-                if kind.is_named() and not any(arg.startswith('*') for arg in args):
-                    args.append('*')
                 if not annotation:
                     typename = self.get_str_type_of_node(arg_.initializer, True, False)
                     if typename == '':

test-data/unit/stubgen.test

@@ -2580,3 +2580,8 @@ class A:
 def f(x: int, y: int) -> int: ...
 @t.overload
 def f(x: t.Tuple[int, int]) -> int: ...
+
+[case testNonDefaultKeywordOnlyArgAfterAsterisk]
+def func(*, non_default_kwarg: bool, default_kwarg: bool = True): ...
+[out]
+def func(*, non_default_kwarg: bool, default_kwarg: bool = ...): ...