Andrew Poelstra e7521fa225 Merge rust-bitcoin/rust-bitcoin#1710: Support weight prediction in `const` context ... 00b46d6d9d Indent functions (Martin Habovstiak) d56d202aeb Support weight prediction in `const` context (Martin Habovstiak) Pull request description: **Notes for reviewers:** This is something that I want to use in my code and hopefully reasonably easy to review, so if this can get into 0.30 that'd be really nice. No hard feelings if it doesn't. I tried to put extra effort into making review easier by: * intentionally "mis-formatting" the first commit so diff is smaller and easy to understand - see individual commits. * copying patterns from non-const fn to const fn so it's obviously correct (includes same variable names) * not bothering with the array trick in `VarInt::len` and simply accepting the limitation of Rust 1.46+ (I use 1.48 BTW). **Description** Some smart contracts or simplified wallets statically know the sizes of transactions or inputs. The possible approaches to handling them so far were re-computing the values (and hoping the optimizer will const fold them) or using a simple constant which may be harder to understand and get right. It's much nicer to just use a `const` but our code didn't support it until now. This change adds methods that can compute the prediction in `const` context for Rust versions >= 1.46.0 which allow use of loops (and conditions but those could be workaround anyway). As a side effect of this, the change also adds `const` to `VarInt::len` in Rust 1.46+. While this one could be made unconditional using array trick it's probably not worth it because of the planned MSRV bump. ACKs for top commit: apoelstra: ACK 00b46d6d9d tcharding: ACK 00b46d6d9d Tree-SHA512: 5509886a68b4de5227db0e28d92a40be8de64592e0b189c519213db21bcfe98ca03d9a1936b1024729b97db69e8ec0b55fac870a7ce9bab0d0c9a47b2087990f		2023-03-19 13:22:34 +00:00
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contrib	Fix CI builds where default features are added accidentally	2023-03-12 20:24:55 +00:00
embedded	Instruct devs to use nightly for embedded	2023-02-03 08:44:47 +11:00
examples	Run the formatter	2023-03-06 10:22:29 +11:00
fuzz	Add a newtype for script-pushable slice	2023-02-18 16:35:25 +01:00
src	Merge rust-bitcoin/rust-bitcoin#1710: Support weight prediction in `const` context	2023-03-19 13:22:34 +00:00
tests	Run the formatter	2023-03-06 10:22:29 +11:00
CHANGELOG.md	add some documentation clarifying the locktime ordering shenanigans in #1330	2022-12-15 23:12:03 +00:00
Cargo.toml	rename bitcoin-internals to bitcoin-private	2023-03-13 16:02:12 +00:00
build.rs	Exclude usage of atomic types if not supported for the target	2023-03-16 22:42:15 +01:00