undefined method `query' on Nickel (Module)

I noticed that there's a /spec directory (containing rspec tests) as well as the /test directory, but most (or all?) of the tests in there seem to fail, with the error below

  20) A date monthly occurrence should occur once per month
     Failure/Error: @n = Nickel.query "pay credit card every month on the 22nd"
     NoMethodError:
       undefined method `query' on Nickel (Module)
     # kernel/delta/kernel.rb:81:in `query (method_missing)'
     # ./spec/nickel_spec.rb:104:in `__script__'
     # kernel/common/eval19.rb:45:in `instance_eval'
     # kernel/common/eval19.rb:45:in `instance_eval'
     # kernel/bootstrap/array19.rb:18:in `map'
     # kernel/bootstrap/proc.rb:22:in `call'
     # kernel/loader.rb:698:in `run_at_exits'
     # kernel/loader.rb:718:in `epilogue'
     # kernel/loader.rb:851:in `main'

Should these tests be removed? Are they still relevant?