Using Matchers as Predicates Have you noticed that a matcher is just a fancy predicate that also knows how to describe itself? Next, you need a way to say that you want to use ConcretePacketStream in production code, and use MockPacketStream in tests. That’s fine as long as the test doesn’t need to call it. Syntax This subcommand has the following syntax: $ chef env Options This command does not have any specific options. Options This subcommand has the following options: -a, —archive Export an archive as a tarball, instead as a directory.