Let's say we want to develop a simple library gem that lists the people in a user's addressbook.
Let's start by initializing an empty gem directory:
$ gem install bundler $ bundle gem bw-addressbook
Add BubbleWrap and Rake to your gem's dependencies in
Gem::Specification.new do |gem| gem.add_dependency 'bubble-wrap' gem.add_development_dependency 'rake' end
$ bundle Fetching gem metadata from https://rubygems.org/.. Using rake (0.9.2.2) Installing bubble-wrap (0.4.0) Using bw-addressbook (0.0.1) from source at /Users/jnh/Dev/tmp/bw-addressbook Using bundler (1.1.4) Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed.
lib/bw-addressbook.rb to include:
require 'bw-addressbook/version' BW.require 'motion/address_book.rb'
Edit your project's
Rakefile to include:
#!/usr/bin/env rake $:.unshift("/Library/RubyMotion/lib") require 'motion/project' require "bundler/gem_tasks" Bundler.setup Bundler.require require 'bubble-wrap/test'
At this point we should have a working RubyMotion environment able to compile our code as we write it.
Let's start by creating a spec for our address book gem in
describe AddressBook do describe '.list' do it 'returns an Enumerable' do AddressBook.list.is_a?(Enumerable).should == true end end end
Now if you run
rake spec you can watch the spec fail:
2012-06-07 11:19:35.506 Untitled[14987:f803] *** Terminating app due to uncaught exception 'NameError', reason: 'uninitialized constant AddressBook (NameError)' *** First throw call stack: (0x8f6022 0x286cd6 0x140054 0x291f 0x2645 0x1) terminate called throwing an exception
Let's go and define ourselves an
AddressBook class in
class AddressBook end
You'll now get a spec failure:
NoMethodError: undefined method `list' for AddressBook:Class spec.rb:156:in `block in run_spec_block': .list - returns an Enumerable 4:in `execute_block' spec.rb:156:in `run_spec_block' spec.rb:171:in `run'
Well, we'd better go and define it then, eh?
class AddressBook def self.list  end end
I'm going to leave it here for now, but you're welcome to take a look at the fully working demonstration project on Github.