lnchan refactor

- replace undoing logic with new HTLCManager class
- separate SENT/RECEIVED
- move UpdateAddHtlc to lnutil

electrum/tests/test_lnhtlc.py

@@ -0,0 +1,95 @@
+import unittest
+from electrum.lnutil import RECEIVED, LOCAL, REMOTE, SENT, HTLCOwner
+from electrum.lnhtlc import HTLCManager
+from typing import NamedTuple
+
+class H(NamedTuple):
+    owner : str
+    htlc_id : int
+
+class TestHTLCManager(unittest.TestCase):
+    def test_race(self):
+        A = HTLCManager()
+        B = HTLCManager()
+        ah0, bh0 = H('A', 0), H('B', 0)
+        B.recv_htlc(A.send_htlc(ah0))
+        self.assertTrue(B.expect_sig[RECEIVED])
+        self.assertTrue(A.expect_sig[SENT])
+        self.assertFalse(B.expect_sig[SENT])
+        self.assertFalse(A.expect_sig[RECEIVED])
+        self.assertEqual(B.log[REMOTE]['locked_in'][0][LOCAL], 1)
+        A.recv_htlc(B.send_htlc(bh0))
+        self.assertTrue(B.expect_sig[RECEIVED])
+        self.assertTrue(A.expect_sig[SENT])
+        self.assertTrue(A.expect_sig[SENT])
+        self.assertTrue(B.expect_sig[RECEIVED])
+        self.assertEqual(B.current_htlcs(LOCAL), [])
+        self.assertEqual(A.current_htlcs(LOCAL), [])
+        self.assertEqual(B.pending_htlcs(LOCAL), [(RECEIVED, ah0)])
+        self.assertEqual(A.pending_htlcs(LOCAL), [(RECEIVED, bh0)])
+        A.send_ctx()
+        B.recv_ctx()
+        B.send_ctx()
+        A.recv_ctx()
+        self.assertEqual(B.pending_htlcs(LOCAL), [(RECEIVED, ah0), (SENT, bh0)][::-1])
+        self.assertEqual(A.pending_htlcs(LOCAL), [(RECEIVED, bh0), (SENT, ah0)][::-1])
+        B.send_rev()
+        A.recv_rev()
+        A.send_rev()
+        B.recv_rev()
+        self.assertEqual(B.current_htlcs(LOCAL), [(RECEIVED, ah0), (SENT, bh0)][::-1])
+        self.assertEqual(A.current_htlcs(LOCAL), [(RECEIVED, bh0), (SENT, ah0)][::-1])
+
+    def test_no_race(self):
+        A = HTLCManager()
+        B = HTLCManager()
+        B.recv_htlc(A.send_htlc(H('A', 0)))
+        self.assertEqual(len(B.pending_htlcs(REMOTE)), 1)
+        A.send_ctx()
+        B.recv_ctx()
+        B.send_rev()
+        A.recv_rev()
+        B.send_ctx()
+        A.recv_ctx()
+        A.send_rev()
+        B.recv_rev()
+        self.assertEqual(len(A.current_htlcs(LOCAL)), 1)
+        self.assertEqual(len(B.current_htlcs(LOCAL)), 1)
+        B.send_settle(0)
+        A.recv_settle(0)
+        self.assertEqual(A.htlcs_by_direction(REMOTE, RECEIVED), [H('A', 0)])
+        self.assertNotEqual(A.current_htlcs(LOCAL), [])
+        self.assertNotEqual(B.current_htlcs(REMOTE), [])
+        self.assertEqual(A.pending_htlcs(LOCAL), [])
+        self.assertEqual(B.pending_htlcs(REMOTE), [])
+        B.send_ctx()
+        A.recv_ctx()
+        A.send_rev()
+        B.recv_rev()
+        A.send_ctx()
+        B.recv_ctx()
+        B.send_rev()
+        A.recv_rev()
+        self.assertEqual(B.current_htlcs(LOCAL), [])
+        self.assertEqual(A.current_htlcs(LOCAL), [])
+        self.assertEqual(A.current_htlcs(REMOTE), [])
+        self.assertEqual(B.current_htlcs(REMOTE), [])
+        self.assertEqual(len(A.settled_htlcs(LOCAL)), 1)
+        self.assertEqual(len(A.sent_in_ctn(2)), 1)
+        self.assertEqual(len(B.received_in_ctn(2)), 1)
+
+    def test_settle_while_owing(self):
+        A = HTLCManager()
+        B = HTLCManager()
+        B.recv_htlc(A.send_htlc(H('A', 0)))
+        A.send_ctx()
+        B.recv_ctx()
+        B.send_rev()
+        A.recv_rev()
+        B.send_settle(0)
+        A.recv_settle(0)
+        self.assertEqual(B.pending_htlcs(REMOTE), [])
+        B.send_ctx()
+        A.recv_ctx()
+        A.send_rev()
+        B.recv_rev()