From ede54330fb38866936c63ebb96c490a2d4b1b58c Mon Sep 17 00:00:00 2001
From: Simon Sawicki <contact@grub4k.dev>
Date: Fri, 16 Jan 2026 15:53:32 +0100
Subject: [PATCH] [utils] `devalue`: Fix calling reviver on cached value
 (#15568)

Authored by: Grub4K
---
 test/test_devalue.py          | 6 +++++-
 yt_dlp/utils/jslib/devalue.py | 4 ++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/test/test_devalue.py b/test/test_devalue.py
index 29eb89e87f..a9fdf8c919 100644
--- a/test/test_devalue.py
+++ b/test/test_devalue.py
@@ -227,9 +227,13 @@ class TestDevalue(unittest.TestCase):
             {'a': 'b'}, 'revivers (indirect)')
 
         self.assertEqual(
-            devalue.parse([['parse', 1], '{"a":0}'], revivers={'parse': lambda x: json.loads(x)}),
+            devalue.parse([['parse', 1], '{"a":0}'], revivers={'parse': json.loads}),
             {'a': 0}, 'revivers (parse)')
 
+        self.assertEqual(
+            devalue.parse([{'a': 1, 'b': 3}, ['EmptyRef', 2], 'false', ['EmptyRef', 2]], revivers={'EmptyRef': json.loads}),
+            {'a': False, 'b': False}, msg='revivers (duplicate EmptyRef)')
+
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/yt_dlp/utils/jslib/devalue.py b/yt_dlp/utils/jslib/devalue.py
index ac5bd68577..f3a6e18441 100644
--- a/yt_dlp/utils/jslib/devalue.py
+++ b/yt_dlp/utils/jslib/devalue.py
@@ -62,10 +62,10 @@ def parse_iter(parsed: typing.Any, /, *, revivers: dict[str, collections.abc.Cal
         if isinstance(source, tuple):
             name, source, reviver = source
             try:
-                resolved[source] = target[index] = reviver(target[index])
+                target[index] = reviver(target[index])
             except Exception as error:
                 yield TypeError(f'failed to parse {source} as {name!r}: {error}')
-                resolved[source] = target[index] = None
+                target[index] = None
             continue
 
         if source in resolved: