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

def test_eraseToLineBeginning(self):

    self.protocol.eraseToLineBeginning()
    self.assertEqual(self.transport.value(), ((self.CSI + '1') + CSFinalByte.EL.value))
