For the last couple of weeks, I've got my hands dirty with JRuby. With the main goal of making Rails test suite green(er) on JRuby I used it as an opportunity to dive into JRuby internals.
$ chruby jruby-9.1.6.0 $ cd ~/Projects/opensource/rails $ jruby -S bundle install $ cd activemodel # running all activemodel tests $ jruby -S bundle exec rake test # running single test file $ jruby -S bundle exec ruby -Itest test/cases/failing_test.rb # running single test case $ jruby -S bundle exec ruby -Itest test/cases/failing_test.rb -n test_spefici_failing
The process of developing Rails on JRuby was pretty easy, until I got into a situation when I fixed a couple on bugs in JRuby master and I wanted to run tests against my own build of JRuby.
Assuming my build of JRuby master is located in ~/Projects/opensource/jruby/bin/jruby
$ cd ~/Projects/opensource/rails/activemodel $ ~/Projects/opensource/jruby/bin/jruby --dev -S bundle exec ruby -v ruby 2.0.0p648 (2015-12-16 revision 53162) [universal.x86_64-darwin16]
WTF? It looks like bundle exec doesn't respect the JRuby environment.
At the same time, we should remember that bundle exec is just a wrapper around require 'bundler/setup.
The following command successfully runs decimal_test.rb from ActiveModel:
$ ~/Projects/opensource/jruby/bin/jruby --dev -rbundler/setup -Itest test/cases/type/decimal_test.rb # to run complete test suite $ ~/Projects/opensource/jruby/bin/jruby --dev -rbundler/setup -S rake test
Talking about JRuby internals, I was amazed with how readable they are when compared with MRI C sources. So faw I managed to fix two issues and all of them required to write a bit of Java code. That felt quite easy. I don't imagine how much time I would spend if I had to do the same with C code in MRI.
