Feature: support testnet4

[antonilol]

Bitcoin Core PR: bitcoin/bitcoin#29775
Maybe an update from the bitcoin crate is needed, but it could be that simply changing some constants (port, data dir, ...) can get it to work too

[nikicat]

Draft patch for testnet4

[antonilol]

That seems way too complicated, I think it would be best to wait for rust-bitcoin to add testnet4 support in some way, I see they are also improving the way networks are handled, see rust-bitcoin/rust-bitcoin#2749

[nikicat]

It's indeed complicated, but from my point of view, it's less complicated than refactoring rust-bitcoin and gives the working solution right now. I do not propose it as a PR though, I just wanted to leave the link here if someone needs it.

[romanz]

Thanks for opening this issue!
I prefer to wait for proper Testnet4 support from rust-bitcoin/rust-bitcoin#2749.

[twofaktor]

https://github.com/bitcoin/bitcoin/releases/tag/v28.0

[romanz]

rust-bitcoin/rust-bitcoin#2749 is being backported to 0.32.x by rust-bitcoin/rust-bitcoin#3453.

[antonilol]

Note that because the backport may not be a breaking change, it will be slightly different (adds a Testnet4 enum variant to Network instead of a new TestnetVersion field in Network::Testnet), see rust-bitcoin/rust-bitcoin#3453 (comment)

[junderw]

The backport got ACKed, so expect 0.32.4 soon-ish.

It will be backwards compatible unlike the new network API on master.

[romanz]

Merged in #1104 - thanks @junderw!