Add GitHub Actions CI

[sethaxen]

Testing out using GitHub Actions as CI, as proposed in #144.

[codecov]

Codecov Report

Merging #147 into master will decrease coverage by 3.86%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #147      +/-   ##
==========================================
- Coverage   97.68%   93.82%   -3.87%     
==========================================
  Files          48       48              
  Lines        3154     3012     -142     
==========================================
- Hits         3081     2826     -255     
- Misses         73      186     +113

Impacted Files	Coverage Δ
src/groups/group.jl	75.13% <0%> (-22.25%)	⬇️
src/groups/translation_action.jl	81.25% <0%> (-18.75%)	⬇️
src/manifolds/Hyperbolic.jl	85.36% <0%> (-14.64%)	⬇️
src/manifolds/Grassmann.jl	88.88% <0%> (-11.12%)	⬇️
src/groups/metric.jl	84.61% <0%> (-11.04%)	⬇️
src/SizedAbstractArray.jl	80.48% <0%> (-9.99%)	⬇️
src/product_representations.jl	87.35% <0%> (-9.42%)	⬇️
src/manifolds/Circle.jl	90.83% <0%> (-9.17%)	⬇️
src/manifolds/Stiefel.jl	92.3% <0%> (-7.7%)	⬇️
src/manifolds/Euclidean.jl	91.35% <0%> (-7.48%)	⬇️
... and 20 more

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[mateuszbaran]

Do we need to trigger it on both push and pull_request?

[kellertuer]

For documenter you might want to generate a set of keys – and do the GitHub Actions have a variable environment? You should then add the key as described here https://juliadocs.github.io/Documenter.jl/stable/man/hosting/#GitHub-Actions-1 – and since this is a different config file, a separate key should work, so we don't have to use the travis one twice. Or wa can anyways decide to do just one deploy (the one here?).

[sethaxen]

35 minutes to run the entire CI is pretty nice! Should be even lower with #146

Do we need to trigger it on both push and pull_request?

No, I'm going to remove push.

For documenter you might want to generate a set of keys – and do the GitHub Actions have a variable environment? You should then add the key as described here https://juliadocs.github.io/Documenter.jl/stable/man/hosting/#GitHub-Actions-1 – and since this is a different config file, a separate key should work, so we don't have to use the travis one twice. Or wa can anyways decide to do just one deploy (the one here?).

At the moment, everything seems to work for the docs build. It didn't deploy, but it's not yet configured to deploy the preview build on PRs. Yes, I think ultimately, we'll want to just deploy once. My thinking is that if we like GitHub Actions for CI, then we can remove Travis and Appveyor, since it works on all 3 OSes.

I've heard that codecov doesn't currently work if the branch isn't from the same repo. If we choose to merge this when completed, I'll open a PR from a fork to test this.

[sethaxen]

Okay, this seems to me to be ready for review and possible merging (once tests pass). Perhaps we can run this along with Travis and Appveyor for a little while and see if we like it enough to switch entirely to it.

One thing I noticed that's pretty cool is that when Documenter runs, a "documenter/deploy".
job appears. Clicking "Details" next to that run opens up the preview docs URL!

[kellertuer]

The preview URL is pretty cool, I always had to remember the URL style manually.

I think we can run them in parallel for a while, we just should do the deploy on only one, so remove it from travis maybe?

[sethaxen]

Good idea. Done.

[kellertuer]

The [skip ci] does nor yet seem to work? Can you do that label-based approach?

[sethaxen]

Ah, it's not supposed to work. [skip ci] tells both Travis and Appveyor not to run on that commit. I was just trying to avoid using up the queue with frequent pushing. I might be able to do something similar with GitHub actions, but I'd rather save that for another PR.

…

On Fri, Apr 3, 2020, 4:09 AM Ronny Bergmann ***@***.***> wrote: The [skip ci] does nor yet seem to work? Can you do that label-based approach? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#147 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACCFSYSFFS26ESU4DDVJX73RKW7XXANCNFSM4L2ESZDQ> .

[kellertuer]

Thanks for the explanation, I wasn't aware of that magic part to avoid ci. Then this PR is fine with me.

[sethaxen]

The one thing to watch out for is Appveyor requires it in the title, while Travis reads title and description. Which I forgot for this PR, so when I merged it, the squashed commit description includes [skip ci], so Travis didn't run on the commit to master, while Appveyor did. The solution is editing the description before squashing to remove all [skip ci].