1)
MissingSourceFile in 'Merb::Gems.required called without a block should return a hash of required gems'
no such file to load -- --- 
merb-plugin-that-does-not-exist: 
  version: 0.1.2
before:
  version: 0.1.2
  when: before
explicit-after:
  version: 1.2.1
  when: after
implied-after:
  version: 1.1.1
./specs/merb/../../lib/merb/gems.rb:96:in `with_manifest'
./specs/merb/../../lib/merb/gems.rb:95:in `with_manifest'
./specs/merb/../../lib/merb/gems.rb:31:in `list_required'
./specs/merb/../../lib/merb/gems.rb:30:in `list_required'
./specs/merb/../../lib/merb/gems.rb:26:in `required'
./specs/merb/merb_gems_spec.rb:23: