Refactoring is defined as the process by which you restructure code without changing its external behaviour. So in other words, refactoring should never break tests because the external features of the code do not change.
Now - redesign or rewriting code is a very different thing. Refactoring can lay the groundwork for redesign or component level rewrites. But the process of redesign and rewrites could result in breakages unless the right level of isolating layers are put in place. This usually involves lots of work to keep tests working.
Personally I have found that unit tests don't result in less work. They are a LOT of work and will continue to be a lot of work if they are to generate value. What they offer though is the ability to know when things have gone wrong and the confidence to release and deploy. I realize that you don't get increased confidence in your release process by doing less work. Software it appears, like almost everything else, obeys the basic laws of thermodynamics. :)
I hope this helps- but Go is not a build tool - but a deployment pipeline tool.
Go runs builds on your machines and can call out to various build tools- like Ant, Nant, rake - or if all else fails- the shell. So anything you can run on the command line of your machine (either windows or *nix) can be automated by Snap.
The key point here is that it is automated deployment, not automatic deployment. Without an automated manually gated trigger, you would end up deploying every gem that got built to rubygems.org, which would be very broken for gems.
Another possibility- and something people do often is to maintain a release branch and merging all changes from the master/development branch onto this one when something is ready to be released. The gem built from this release branch can then be released automatically every time it is built.
The fact is, that flow too, can be automated from Snap due to our automated branch tracking.
RSpec (rspec-core at least), and many other gems, use TravisCI to do the testing but not the pushing.
Refactoring is defined as the process by which you restructure code without changing its external behaviour. So in other words, refactoring should never break tests because the external features of the code do not change.
Now - redesign or rewriting code is a very different thing. Refactoring can lay the groundwork for redesign or component level rewrites. But the process of redesign and rewrites could result in breakages unless the right level of isolating layers are put in place. This usually involves lots of work to keep tests working.
Personally I have found that unit tests don't result in less work. They are a LOT of work and will continue to be a lot of work if they are to generate value. What they offer though is the ability to know when things have gone wrong and the confidence to release and deploy. I realize that you don't get increased confidence in your release process by doing less work. Software it appears, like almost everything else, obeys the basic laws of thermodynamics. :)