I am trying to build a datamapper adapter and I'm having trouble getting started. With the following files, I get the resulting NameError when I run rspec spec/dm-mongolitedb-adapter_spec.rb

gistfile1.txt

lib/dm-mongolitedb-adapter.rb
  
  1 require 'dm-core'
  2 require 'dm-core/adapters/abstract_adapter'
  3 require 'mongolitedb'
  4
  5 module DataMapper
  6     module Adapters
  7         class MongoLiteDBAdapter < AbstractAdapter
  8             private
  9             def initialize(name, options = {})
 10                 super
 11                 @db = MongoLiteDB.new
 12             end
 13         end
 14         const_added(:MongoLiteDBAdapter)
 15     end
 16 end

spec/dm-mongolitedb-adapter_spec.rb

  1 require 'dm-core/spec/shared/adapter_spec'
  2 require_relative '../lib/dm-mongolitedb-adapter.rb'
  3
  4 describe 'Adapter' do
  5     describe 'DataMapper::Adapters::MongoLiteDBAdapter' do
  6       before :all do
  7         @adapter = DataMapper.setup(:default, :adapter   => 'mongolitedb')
  8       end
  9       it_should_behave_like 'An Adapter'
 10     end
 11 end

/Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/dm-core-1.2.0/lib/dm-core/spec/shared/adapter_spec.rb:21:in `block in adapter_supports?': undefined local variable or method `described_type' for #<Class:0x007fc9c727ef78> (NameError)
  from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/dm-core-1.2.0/lib/dm-core/spec/shared/adapter_spec.rb:15:in `each'
  from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/dm-core-1.2.0/lib/dm-core/spec/shared/adapter_spec.rb:15:in `all?'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/dm-core-1.2.0/lib/dm-core/spec/shared/adapter_spec.rb:15:in `adapter_supports?'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/dm-core-1.2.0/lib/dm-core/spec/shared/adapter_spec.rb:45:in `block in <top (required)>'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/extensions/module_eval_with_args.rb:13:in `module_exec'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/extensions/module_eval_with_args.rb:13:in `module_eval_with_args'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:167:in `find_and_eval_shared'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:116:in `block in it_should_behave_like'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:242:in `module_eval'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:242:in `subclass'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:228:in `describe'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:115:in `it_should_behave_like'
	from /Users/peter/repos/dm-mongolitedb-adapter/spec/dm-mongolitedb-adapter_spec.rb:11:in `block (2 levels) in <top (required)>'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:242:in `module_eval'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:242:in `subclass'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:228:in `describe'
	from /Users/peter/repos/dm-mongolitedb-adapter/spec/dm-mongolitedb-adapter_spec.rb:7:in `block in <top (required)>'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:242:in `module_eval'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:242:in `subclass'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/example_group.rb:228:in `describe'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/dsl.rb:18:in `describe'
	from /Users/peter/repos/dm-mongolitedb-adapter/spec/dm-mongolitedb-adapter_spec.rb:6:in `<top (required)>'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/configuration.rb:819:in `load'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/configuration.rb:819:in `block in load_spec_files'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/configuration.rb:819:in `each'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/configuration.rb:819:in `load_spec_files'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/command_line.rb:22:in `run'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/runner.rb:80:in `run'
	from /Users/peter/.rvm/gems/ruby-2.0.0-p0/gems/rspec-core-2.13.1/lib/rspec/core/runner.rb:17:in `block in autorun'