'L{ConsoleUI.prompt} writes a message to the console, then reads a line.
If that line is \'yes\', then it returns a L{Deferred} that fires with
True.'

def test_promptYes(self):

    for okYes in ['yes', 'Yes', 'yes\n']:
        self.newFile([okYes])
        l = []
        self.ui.prompt('Hello,    world!').addCallback(l.append)
        self.assertEqual(['Hello,    world!'], self.fakeFile.outchunks)
        self.assertEqual([True], l)
        self.assertTrue(self.fakeFile.closed)
