Tools: Travis should check releases

[ewels]

Travis builds on pushes, PRs and also tags (which for us are the same as releases). It would be great if there could be a set of tests which are specific to releases.

Suggestions:

• [x] Introduce --release flag for nf-core lint
• [x] Conditionally execute lint tests with --release flag, when git activity happens on the master branch (check env var TRAVIS_BRANCH)

On --release set:

• [x] Check that the version variable is numeric-only
• [x] Check that the docker slug has a tag which isn't latest
• [x] Check that the tag name (release number) is the same as the config version and container label.

Bonus points for challenging ones:

• [ ] Check that fixed bioconda package versions are the latest available (warn if not)

[ewels]

If we always develop in a develop branch, these tests could instead just run whenever a push goes to the master branch. Then we have a chance to catch failures before we push the release.

[apeltzer]

I'd be even happier with that kind of best practices: Branches are good to keep things like the master branch stable. Just imagine we'd have merged my commits this morning without further testing ;-)

[sven1103]

What do you have in mind? A --release flag for lint, that additionally checks the points above? We could then use the TRAVIS_BRANCH env var in order to differentiate between master and develop.

[ewels]

I was just thinking of getting Python to look for the env var or the git branch name. But a --release command line flag is even better as then it's easy to soft-test it before pushing. Then we can just have a conditional test that runs with this flag if it's on master...

[sven1103]

exactly what i was thinking :)

[sven1103]

I just updated your first comment @ewels, hope that's ok :)

[sven1103]

Opened an issue, so we modify the travis.yml accordingly in the template: https://github.com/nf-core/cookiecutter/issues/16

[ewels]

I think move the bioconda thing into a separate issue, then this is done 👍

Nice job @sven1103!