Fix crash on multiple unpacks in a bare type application (#18857)

Fixes #18856. This should be done by `TypeAnalyzer.anal_array` but is
not - semanal only invokes its own wrapper around `anal_type`

---------

Co-authored-by: Ivan Levkivskyi <[email protected]>

Author: 2 people

mypy/semanal.py

@@ -6041,6 +6041,8 @@ def analyze_type_application_args(self, expr: IndexExpr) -> list[Type] | None:
                 return None
             types.append(analyzed)
 
+        if allow_unpack:
+            types = self.type_analyzer().check_unpacks_in_list(types)
         if has_param_spec and num_args == 1 and types:
             first_arg = get_proper_type(types[0])
             single_any = len(types) == 1 and isinstance(first_arg, AnyType)

mypy/typeanal.py

@@ -2006,7 +2006,7 @@ def check_unpacks_in_list(self, items: list[Type]) -> list[Type]:
 
         if num_unpacks > 1:
             assert final_unpack is not None
-            self.fail("More than one Unpack in a type is not allowed", final_unpack)
+            self.fail("More than one Unpack in a type is not allowed", final_unpack.type)
         return new_items
 
     def tuple_type(self, items: list[Type], line: int, column: int) -> TupleType: