Run clippy on Travis-CI

[spl]

This causes Travis-CI to fail if clippy finds any warning lints. It will, of course, fail now, since there are warnings to be found. But if #351 and #352 are merged and this branch is updated, it will pass.

[pkgw]

#351 and #352 are now merged, so if you rebase onto master we should be able to see how this goes. (I tried to do it for you but I guess I haven't enabled the feature that lets maintainers edit other people's PRs directly for this repo.)

[spl]

Rebased.

[spl]

Oh, I just noticed this on Travis-CI:

component 'clippy' for target 'x86_64-unknown-linux-gnu' is unavailable for download for channel 'nightly'

[spl]

I guess clippy isn't always available for nightly. See this rustup components history. I'm not sure what “present” and “missing” mean. Perhaps it's missing if it fails to build? Perhaps rustup component add clippy should not be run for the nightly CI.

[spl]

But it's nice to see Travis-CI passing for stable. 🙂

[pkgw]

@spl Yes, I believe that for non-core components such as clippy, it's not guaranteed that they'll be available on nightly. Based on the small sample size, it looks like that happens non-negligibly often, but nightly failures are OK anyway so I don't think we need to do anything special to deal with those failures. Stable and beta will always have clippy, I think.

[codecov]

Codecov Report

Merging #353 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #353   +/-   ##
=======================================
  Coverage   39.61%   39.61%           
=======================================
  Files         135      135           
  Lines       59496    59496           
=======================================
  Hits        23569    23569           
  Misses      35927    35927

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[spl]

I think it's better to to avoid spurious failures even for nightly. That way, a (non-network-related) failure is a valid failure that may deserve inspection. So, I pushed the rustup operations after the $is_main_build check to avoid fetching rustfmt and clippy for other CI runs.

[pkgw]

👍