This moves to Rust 1.86 as were prior on Rust 1.81, and the new alloy
dependencies require 1.82.
The revm API changes were notable for us. Instead of relying on a modified call
instruction (with deep introspection into the EVM design), we now use the more
recent and now more prominent Inspector API. This:
1) Lets us perform far less introspection
2) Forces us to rewrite the gas estimation code we just had audited
Thankfully, it itself should be much easier to read/review, and our existing
test suite has extensively validated it.
This resolves 001 which was a concern for if/when this upgrade occurs. By doing
it now, with a dedicated test case ensuring the issue we would have had with
alloy-core 0.8 and `validate=false` isn't actively an issue, we resolve it.
It had sequential async calls with complexity O(n), with a variety of redundant
calls. There was also a constant of... 4? 5? for each item. Now, the total
sequence depth is just 3-4.
Completes the `Executed` enum in the router. Adds an `Escape` struct. Both are
needed for testing purposes.
Documents the gas constants in intent and reasoning.
Adds modernized tests around key rotation and the escape hatch.
Also updates the rest of the codebase which had accumulated errors.
The router will now match the top-level transfer so it isn't used as the
justification for the InInstruction it's handling. This allows the theoretical
case where a top-level transfer occurs (to any entity) and an internal call
performs a transfer to Serai.
Also uses a JoinSet for fetching transactions' top-level transfers in the ERC20
crate. This does add a dependency on tokio yet improves performance, and it's
scoped under serai-processor (which is always presumed to be tokio-based).
While we could instead import futures for join_all,
https://github.com/smol-rs/futures-lite/issues/6 summarizes why that wouldn't
be a good idea. While we could prefer async-executor over tokio's JoinSet,
JoinSet doesn't share the same issues as FuturesUnordered. That means our
question is solely if we want the async-executor executor or the tokio
executor, when we've already established the Serai processor is always presumed
to be tokio-based.