From 39cb150d7608e8e7f3d10a6abbad08345523098e Mon Sep 17 00:00:00 2001
From: bashonly <bashonly@protonmail.com>
Date: Wed, 11 Jun 2025 12:49:08 -0500
Subject: [PATCH] [devalue] better error message for self-referencing custom
 types

Authored by: bashonly
---
 yt_dlp/utils/web/devalue.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/yt_dlp/utils/web/devalue.py b/yt_dlp/utils/web/devalue.py
index a922c7ab2..59c8594a0 100644
--- a/yt_dlp/utils/web/devalue.py
+++ b/yt_dlp/utils/web/devalue.py
@@ -79,7 +79,7 @@ def parse_iter(parsed: typing.Any, /, *, revivers: dict[str, collections.abc.Cal
                 # TODO: implement zips `strict=True`
                 if reviver := revivers.get(value[0]):
                     if value[1] == source:
-                        yield IndexError('custom types cannot point to themselves')
+                        yield IndexError(f'{value[0]!r} cannot point to itself (index: {source})')
                         continue
                     # inverse order: resolve index, revive value
                     stack.append((target, index, (value[0], value[1], reviver)))