fix #16935 strike that: use tuple fallback as tuple[X,...] fallback

urnest · urnest · commit 5bd1c4cc5720 · 2024-06-01T17:49:57.000+10:00
... the original fallback ABCMeta is "correct" in that it aligns
with the (abstract) base class of builtins.tuple. But rather than
explicitly specify abc.ABCMeta as fallback, use the same
fallback as the type we're applying arguments to (and that is
abc.ABCMeta in our "tuple" case)
diff --git a/mypy/checkexpr.py b/mypy/checkexpr.py
@@ -4844,9 +4844,9 @@ def apply_type_arguments_to_callable(
                     return CallableType(
                         [TupleType(list(args), self.chk.named_type("tuple"))],
                         [ARG_POS],
-                        ["p1"],
+                        [None],
                         TupleType(list(args), self.chk.named_type("tuple")),
-                        self.chk.named_type("builtins.type"),
+                        tp.fallback,
                         name="tuple",
                         definition=tp.definition,
                         bound_args=tp.bound_args,
