def testEscapingSinkTransmitsFlagOctetCorrectly(self):
mockSink = MockSink()
escapingSink = EscapingSink(mockSink)
escapingSink.writeFlag()
escapingSink.schedule()
self.assertTrue(escapingSink.isReady())
self.assertEqual([EscapingSink.FLAG()], mockSink.items)
def testEscapingSinkTransmitsOctetCorrectly(self):
mockSink = MockSink()
escapingSink = EscapingSink(mockSink)
escapingSink.write(0x42)
escapingSink.schedule()
self.assertTrue(escapingSink.isReady())
self.assertTrue([0x42] == mockSink.items)
def testFrameTransmitterTransmitsNothingByDefault(self):
tmp = MockSink()
sink = EscapingSink(tmp)
transmitter = FrameTransmitter(sink)
for i in range(0, 5):
transmitter.schedule()
sink.schedule()
self.assertEqual([], tmp.items)
def testFrameTransmitterBecomesReadyOnlyOnceTransmissionComplete(self):
tmp = MockSink()
sink = EscapingSink(tmp)
transmitter = FrameTransmitter(sink)
transmitter.transmit(FrameTransmitter.ACK() + 0x24)
for i in range(0, 5):
self.assertFalse(transmitter.isReady())
transmitter.schedule()
sink.schedule()
self.assertTrue(transmitter.isReady())
def testFrameTransmitterTransmitsAckFrameCorrectly(self):
tmp = MockSink()
sink = EscapingSink(tmp)
transmitter = FrameTransmitter(sink)
transmitter.transmit(FrameTransmitter.ACK() + 0x24)
for i in range(0, 5):
transmitter.schedule()
sink.schedule()
crc = crc_ccitt_update(0xFFFF, FrameTransmitter.ACK() + 0x24)
self.assertEqual([EscapingSink.FLAG(), FrameTransmitter.ACK() + 0x24, crc >> 8, crc & 0xFF, EscapingSink.FLAG()], tmp.items)
def testEscapingSinkTransmitsEscapableOctetCorrectly(self):
mockSink = MockSink()
escapingSink = EscapingSink(mockSink)
escapingSink.write(EscapingSink.FLAG())
escapingSink.schedule()
escapingSink.write(EscapingSink.ESCAPE())
escapingSink.schedule()
self.assertTrue(escapingSink.isReady())
self.assertEqual([
EscapingSink.ESCAPE(),
EscapingSink.FLAG() ^ EscapingSink.MASK(),
EscapingSink.ESCAPE(),
EscapingSink.ESCAPE() ^ EscapingSink.MASK()
], mockSink.items)
def testFrameTransmitterTransmitsUserFrameCorrectly(self):
tmp = MockSink()
sink = EscapingSink(tmp)
transmitter = FrameTransmitter(sink)
transmitter.transmit(0x00, [0x42])
for i in range(0, 6):
transmitter.schedule()
sink.schedule()
crc = crc_ccitt_update(0xFFFF, 0x00)
crc = crc_ccitt_update(crc, 0x42)
self.assertEqual([EscapingSink.FLAG(), 0x00, 0x42, crc >> 8, crc & 0xFF, EscapingSink.FLAG()], tmp.items)
def testEscapingSinkBecomesReadyAfterTransmitting(self):
mockSink = MockSink()
escapingSink = EscapingSink(mockSink)
escapingSink.write(0x42)
escapingSink.schedule()
self.assertTrue(escapingSink.isReady())