'L{ServerProtocol.eraseToDisplayBeginning} writes the control
sequence sequence ending in L{CSFinalByte.ED} a parameter of 1
(from the beginning of the page up to and include the active
present position\'s current location.)'

def test_eraseToDisplayBeginning(self):

    self.protocol.eraseToDisplayBeginning()
    self.assertEqual(self.transport.value(), ((self.CSI + '1') + CSFinalByte.ED.value))
