'Check several ways to specify a spec by hash.'

def _check_hash_parse(self, spec):

    self.check_parse(str(spec), ('/' + spec.dag_hash()))
    self.check_parse(str(spec), ('/    ' + spec.dag_hash()[:5]))
    self.check_parse(str(spec), ((spec.name + '/') + spec.dag_hash()))
    self.check_parse(str(spec), ((((spec.name + '@') + str(spec.version)) + '    /') + spec.dag_hash()[:6]))
