Fix CI

[tcharding]

Currently CI is broken because we use the latest version of rustfmt and clippy in CI. We can resolve the rustfmt issue permanently by removing the required_version config option. We also need to fix the latest clippy warnings.

Done as a single patch so that all patches pass CI.

[Kixunil]

ACK f67e8c5

[apoelstra]

Can you also change the required_version in rustfmt.toml?

Probably we should just remove that line, it seems like it's going to cause more breakage than it saves.

[tcharding]

Whats required_version got to do with current breakages? IIUC required_version is just a minimum so that the config options in rustfmt.toml are all available, or am I misunderstanding its usage. CI constantly uses the latest clippy version and that's why we get failures that are never noticed locally (because I never run cargo update until CI clippy job fails). It would be nice if we could pin the version then update the pin at the same time as the patch that fixes newly introduced warnings so that the whole pipeline of PRs didn't get blocked.

It looks like our new github action toolchain installer is configurable so we should be able to get this idea working. What do you think?

https://github.com/dtolnay/rust-toolchain

[apoelstra]

@tcharding the current CI failure has the line Error: rustfmt version (1.5.2) doesn't match the required version (1.5.1) repeated like 20 times.

This is rustfmt that has a fixed version, not clippy. You are correct about clippy.

[tcharding]

Woops I should have clicked on the CI fail, my bad. Staring at that fail all week in every PR and already I've developed a bad habit - happens so fast.

[tcharding]

Force pushed with the rustfmt change, PR description re-written explaining why.

[apoelstra]

ACK d118415

[apoelstra]

Heh, I guess I could've waited to see if CI was actually fixed...oops.

[tcharding]

Huh, it didn't fix it?

[apoelstra]

I think it did, I just don't know how to tell.

[tcharding]

I rebased this one to check it: #561

[tcharding]

Real time chat via github - I guess I should really set up IRC so we can chat at times like this.