Add initial GitHub actions CI

[Robbepop]

No description provided.

[coveralls]

Coverage decreased (-0.4%) to 80.461% when pulling 0571bf7 on add-GitHub-actions-CI into 130949d on master.

[codecov-io]

Codecov Report

Merging #57 into master will decrease coverage by 0.08%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master      #57      +/-   ##
==========================================
- Coverage   80.47%   80.38%   -0.09%     
==========================================
  Files          23       22       -1     
  Lines        5229     5145      -84     
==========================================
- Hits         4208     4136      -72     
+ Misses       1021     1009      -12     

Impacted Files	Coverage Δ
src/apint/serde_impl.rs	76.29% <0.00%> (-1.57%)	⬇️
src/radix.rs	88.57% <0.00%> (-0.32%)	⬇️
src/apint/rand_impl.rs	92.20% <0.00%> (-0.30%)	⬇️
src/bitwidth.rs	88.88% <0.00%> (-0.18%)	⬇️
src/apint/utils.rs	79.25% <0.00%> (-0.11%)	⬇️
src/apint/casting.rs	76.29% <0.00%> (-0.11%)	⬇️
src/apint/arithmetic.rs	93.33% <0.00%> (-0.10%)	⬇️
src/apint/constructors.rs	97.44% <0.00%> (-0.08%)	⬇️
src/digit.rs	94.20% <0.00%> (-0.05%)	⬇️
src/apint/to_primitive.rs	96.38% <0.00%> (-0.01%)	⬇️
... and 6 more

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[AaronKutch]

There are some CI related commits currently on the end of PR #56. For the miri and debug tests, we need to add a flag to disable most of the fuzz testing. We don't want to get rid of the fuzz testing completely like the current situation is in #56. I want the fuzz testing to run for a few iterations (I'll figure out the practical numbers in a separate PR for issue #47). For now, I would add a flag such as "expensive_tests" that enables the megafuzz module in arithmetic.rs. I think I should just remove the CI commits from #56 and handle all that here.

Does GitHub actions straight up replace the Appveryor and Travis stuff? I did a small amount of searching, but the way these things interact is still very fuzzy in my mind.

[Robbepop]

There are some CI related commits currently on the end of PR #56. For the miri and debug tests, we need to add a flag to disable most of the fuzz testing. We don't want to get rid of the fuzz testing completely like the current situation is in #56. I want the fuzz testing to run for a few iterations (I'll figure out the practical numbers in a separate PR for issue #47). For now, I would add a flag such as "expensive_tests" that enables the megafuzz module in arithmetic.rs. I think I should just remove the CI commits from #56 and handle all that here.

Does GitHub actions straight up replace the Appveryor and Travis stuff? I did a small amount of searching, but the way these things interact is still very fuzzy in my mind.

Having miri testing would be a big win to uncover undefined behaviour bugs.
I have not yet figured out how we can get coverage reports to work but I hope I can get it working soon since it is very important imo.
A crate feature to toggle fuzz testing is very important even without CI.

As soon as GitHub actions works we can get rid of Appveyor and Travis CI.

[Robbepop]

This PR is superseeded by #64. Closed.