Using autotest with exercism's Ruby exercises

autotest.rb

Autotest.add_hook :initialize do |at|
  at.add_mapping %r{^(.*)\.rb$} do |_,m|
    at.files_matching( %r{.*_test.rb} )
  end

  at.add_mapping %r{^.*_test\.rb$} do | file, _|
    file
  end
end

autotest_gist.md

I spent some time (about 4 hours - I'm stubborn) trying to get Ruby ZenTest's autotest working with the Ruby exercises on http://exercism.io. I finally came across a sample autotest in the Rubinius project that got me moving in the right direction.

To get continuous testing working, copy the autotest.rb file into the project directory (e.g., exercism/ruby/hamming) as .autotest and run autotest at the command line. Then in a separate terminal, edit the files. Each time you save changes to either the test file or the code under test, you should see the tests get re-run.

You should have the ZenTest gem installed. If you're using rbenv, make sure you run rbenv rehash after installing ZenTest so that the shims get updated.