Depends on, (very) simple dependency injection for ruby
=======================================================

Dependency injection in most static languages is used to break dependencies between object and layers.

Now Ruby as a language is loosely coupled but that doesn't mean it can benefit from some simple dependency injection, and depends on tries to do this.

To add dependencies simply add depends_on and a list of dependencies. The dependencies will be added to you class so you can call them when ever you like

Examples

class MyAwesomeClass
  depends_on :a_nother_class

  def some_awesome_method
    a_nother_class.do_something_awesome
  end
end

With factory methods

class MyAwesomeClass < ActiveRecord::Base
  depends_on :a_nother_class => lambda{ |owner| owner.country == "UK" ? UKTaxCalculator.new : WorldTaxCalculator.new }
end



Future work

Ideal this should make testing that wee bit easier allowing you to substitute fakes when you want to.

NOTE: this is a very early push mainly to get some feedback. Please send me a message with comments/love/hate/indifference