ci: add script for linting & formatting code

[chungquantin]

Link to issue: #115

• Apply lint suggestion
• Format check all packages
• Apply the format (checkout branch)

[Daanvdplas]

FYI: we have some formatting checks in place here. Here you propose CI to make formatting commits if it doesn't fulfil the requirements. In addition, the nightly formatting is used. The latter is something we were already talking about internally and could perhaps be a good change. Not sure about the auto formatting. What do you think @evilrobot-01?

I do like the approval for executing the CI!

[peterwht]

Thanks for doing this Tin!

• I am okay with auto-applying cargo fmt (maybe not nightly version though)
• I am slightly concerned with auto-applying clippy fixes as they can sometimes introduce unintended side-effects (rarely). I think it would be better to prevent merging until clippy has been resolved by the PR author.

[evilrobot-01]

Nothing against auto-formatting. Nightly allows for a few additional nice things it seems (e.g. grouping imports) if desired, and as shared elsewhere, appears to be in use by the Polkadot SDK: https://github.com/paritytech/polkadot-sdk/blob/master/docs/contributor/STYLE_GUIDE.md.

Agree with Peter, probably best to manually address clippy warnings for now.

[evilrobot-01]

Instead of adding an additional workflow, can we rather rename build.yml to ci.yml and then add these changes into that workflow?

[evilrobot-01]

Also imagine that this might create some 'churn' for those that dont auto-format locally, whereby branch is pushed, CI formats and adds a commit and then local branch is out of sync. This can hopefully be eliminated by a proper local setup, which probably enforces formatting locally more so than currently. Either you sort it out to avoid any hassle, or GH sorts it for you and you have to cope with any hassle.

[Daanvdplas]

Also imagine that this might create some 'churn' for those that dont auto-format locally, whereby branch is pushed, CI formats and adds a commit and then local branch is out of sync. This can hopefully be eliminated by a proper local setup, which probably enforces formatting locally more so than currently. Either you sort it out to avoid any hassle, or GH sorts it for you and you have to cope with any hassle.

For this reason, is it then not more simple if we do a CI check on nightly and have the developer fix it themselves?

[chungquantin]

Hence, I think would be better to have:

• Check clippy and prevent from merging until it is resolved
• For formatting, we still want to apply it automatically to the PR code on pushed to keep the codebase style consistent

[chungquantin]

As there are a huge conflict in this PR, I will close it and create the another.