test_spec.rb

# all checks will "fail", but check date output
#
# fails with: rspec test_spec.rb </dev/null
# works with: rspec test_spec.rb

require 'serverspec'
set :backend, :exec

describe 'test' do

  describe command('date') do
    its(:stdout) { should match /first date output/ }
  end

  describe command('script -qfc "sudo su - -c \'date; sleep 10\'"') do
    its(:stdout) { should match /fail this to show stdout/ }
    its(:stderr) { should match /fail this to show stderr/ }
  end

  describe command('date') do
    its(:stdout) { should match /check date output if >=10s after first date output/ }
  end

end