combinepsbt RPC does not work with P2TR inputs #27219

1. 
   ghost commented at 11:14 am on March 7, 2023: none

   combinepsbt allows to distribute identical PSBTs to peers for signature and consolidate the resulting PSBT. However, this does not work with taproot UTXOs for me.

   Expected behavior

   Combined PSBT should return 'complete': True if all inputs are signed in different PSBTs and finalized with finalizepsbt

   Actual behavior

   Unable to finalize the transaction that was combined from multiple signed PSBTs.

   To reproduce

   PSBT 1

   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
   

   PSBT 2

   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
   

   PSBT 3

   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
   

   PSBT 4

   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
   

   PSBT 5

   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
   

   Combined PSBT:

   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
   

   System information

   Bitcoin Core v24.0.1 and all the above PSBTs are for Signet

2. unknown added the label Bug on Mar 7, 2023
3. 
   achow101 commented at 3:59 pm on March 7, 2023: member

   The combined PSBT is correctly combined, there are just no signatures in any of the PSBTs. There’s nothing to finalize, so it cannot be finalized.
4. 
   ghost commented at 4:20 pm on March 7, 2023: none

   The combined PSBT is correctly combined, there are just no signatures in any of the PSBTs. There’s nothing to finalize, so it cannot be finalized.

   This wasn’t don’t manually, all PSBTs passed through walletprocesspsbt, I used the same code for segwit inputs and it worked. I will re-test everything although fractalenrypt told me this can be fixed with an open PR: https://twitter.com/FractalEncrypt/status/1633073353580859396

5. 
   achow101 commented at 4:22 pm on March 7, 2023: member

   Yes, it is a bug in signing, not in combining.
6. 
   fanquake commented at 8:50 am on March 8, 2023: member

   Ok. So this is fixed/closed by #23502 (assume the same for one of the alternate PRs).
7. MarcoFalke added the label PSBT on Mar 8, 2023

Contributors
ghost achow101 fanquake

Labels
Bug PSBT