Hook up code-coverage

[phayes]

Hi there,

I was wondering if you could hook up code-coverage reporting (I personally like codecov, but coveralls and others would be fine too).

Once this is done, I will work on getting code coverage up to 100% (or as close as possible).

Check out the travis.yml file over at https://github.com/phayes/rsa-fdh for an example of how to do it.

[planck-length]

Hi I recently used cargo-tarpaulin to set up code coverage on a rust project. I could help to set it up if you would like, just let me know.

[tarcieri]

We ran Tarpaulin+Codecov on the @RustCrypto/AEADs repo in CI in the past. It was rather noisy and not something I found myself consulting with regularity.

What would be a lot more helpful than just deploying a tool is if someone could go through the coverage report and identify good candidates for code which doesn't currently have test coverage but should and open issues about it.