'CompleteDirs produces zsh shell-code that completes directory names.'

def test_dirs(self):

    c = usage.CompleteDirs()
    got = c._shellCode('some-option', usage._ZSH)
    self.assertEqual(got, ':some-option:_directories')
    c = usage.CompleteDirs(descr='some    action', repeat=True)
    got = c._shellCode('some-option', usage._ZSH)
    self.assertEqual(got, '*:some    action:_directories')
