Gem Init

This is the code I use to set up a new Ruby Gem.

Github and Rubygems.org make it ridiculously easy to share your code using Gems. Sometimes I have something small and useful I'd like to make a gem, but I'm too lazy to set up all the packaging boilerplate, and I prefer not to introduce tools like Jewler or Hoe just to manage a gemspec, which is a trivially easy file to maintain. Setting up a new gem is boring, so I spent a couple hours putting this together as a reusable gem. If you like it, please feel free to use it for whatever purpose you choose. Bug fixes, and patches are of course welcome.

Using it:

gem install gem_init
gem_init hello_world

A brief summary of some of the quirkiness is below:

Your name, email and Github user name

These are read from your ~/.gitconfig if available and used to populate some basic info in the gemspec.

MIT-LICENSE

This is the license I almost always use for my open source work, so it's the default.

Gemfile.default

I prefer not to check my Gemfiles into git, because I usually tweak it a lot when testing against lots of different versions of my dependencies. So I usually just add a Gemfile.default with something that should work, and copy that to Gemfile before working.

The only thing added by default to the Gemfile is your generated library itself, which is an easy way to avoid messing around with the LOAD_PATH in your test setup.

I am assuming Bundler version 1.0.x, which you can currently get by doing

gem install bundler --pre

But by the time you're reading this, it may already be the current stable release.

test_helper.rb

This just adds a test method to the Module class, so you can write declarative tests:

test "something should do something" do
  assert_equal foo, bar
end

Having this as a class method in Module means you can write your unit tests in either modules or classes. Being able to group related tests in modules and give them declarative names for me is "good enough" to make up for Test::Unit's ugliness, and I like the fact that it's just plain old Ruby.

I tend to do this rather than use a bigger test framework, because it introduces less dependencies and makes it very easy for people to just check out my gem and run my tests with the minimum of effort.

*.gemspec

Rather than manually specifying everything, I just pull the files I want to add to the gem out of the list of files added to Git. This works fine most of the time, with the only caveat being that you need to have your stuff in Git before building your gem, or using the directory as a gem via Bundler.

Rakefile

This adds a soft dependency on Yard; the task is added only if you have it installed.

Otherwise, by default a gem method is added to package your gem, and a clean method is there to tidy up your repository.

.gitignore

By default, I ignore Gemfile, Gemfile.lock, pkg and doc directories. Obviously you can and should change this to whatever makes sense for you.

README.md

I like to use Markdown for my README files, as it plays nicely with Yard.