2481695b45 Add tests for BIP-373 PSBT_{IN,OUT}_MUSIG2_PARTICIPANT_PUBKEYS serialization and deserialization (Daniel Roberts)
3e8e6d9aa1 Add BIP-373 PSBT_{IN,OUT}_MUSIG2_PARTICIPANT_PUBKEYS serialization and deserialization (Daniel Roberts)
Pull request description:
This change adds support for serializing and deserializing two PSBT keys from BIP-373: `PSBT_IN_MUSIG2_PARTICIPANT_PUBKEYS` and `PSBT_OUT_MUSIG2_PARTICIPANT_PUBKEYS`
This is a part of #4207 that can be implemented independently of the rest (which depends on https://github.com/rust-bitcoin/rust-secp256k1/pull/716). I believe this satisfactorily avoids changing things multiple times on end users, *however* it's not *completely* transparent to end users, since any code that currently accesses these fields through `unknown` will need to be updated. Later, when `PSBT_IN_MUSIG2_PUB_NONCE` and `PSBT_IN_MUSIG2_PARTIAL_SIG` are supported, code will need to be updated a second time to retrieve them from the correct place instead of `unknown`. I'm of the opinion that this imposes a very minor maintenance burden, only consisting of *removing* deserialization code.
### Notes/Requests for feedback
- For the most part I used my judgement rather than `cargo fmt` since `cargo fmt` already had a lot of other complaints, but of course I'll update if I need to.
- To satisfy the requirement that every commit pass tests, the commit updating the psbt serde regression test should probably be squashed into the first commit, but I just wanted to confirm that before I did it. I suppose similarly, the test commit could be squashed as well?
- I waffled between `musig2_participants` and `musig2_participant_pubkeys`, but I've decided to go with `musig2_participant_pubkeys` because that is consistent with Bitcoin Core
ACKs for top commit:
tcharding:
ACK 2481695b45
apoelstra:
ACK 2481695b456bcccbb25c247c1fd39bbda24dbb30; successfully ran local tests
Tree-SHA512: af884923593c9cbb24ff3f1f08219458538592fabde85d5d65bc2d9bc7bf0b1a73dac38d2c56303b4f3162088db129ea7e879c3d4b324e965933c121ef939a07
5e0b86d2b1