splice: Add test of “splice” script command

Tests that splice-in and splice-out work through the scripting process and confirm the resulting balances are correct.

contrib/pyln-client/pyln/client/lightning.py

@@ -1156,6 +1156,20 @@ def openchannel_abort(self, channel_id):
         }
         return self.call("openchannel_abort", payload)
 
+    def splice(self, script, dryrun=None, psbt=None, user_provided_sats=None, force_feerate=None, json=None, debug_log=None, wetrun=None):
+        """ Execute a splice """
+        payload = {
+            "script": script,
+            "dryrun": dryrun,
+            "psbt": psbt,
+            "user_provided_sats": user_provided_sats,
+            "force_feerate": force_feerate,
+            "json": json,
+            "debug_log": debug_log,
+            "wetrun": wetrun,
+        }
+        return self.call("splice", payload)
+
     def splice_init(self, chan_id, amount, initialpsbt=None, feerate_per_kw=None):
         """ Initiate a splice """
         payload = {

tests/test_splice.py

@@ -0,0 +1,60 @@
+from fixtures import *  # noqa: F401,F403
+import pytest
+import unittest
+from utils import (
+    TEST_NETWORK, only_one
+)
+
+
+@pytest.mark.openchannel('v1')
+@pytest.mark.openchannel('v2')
+@unittest.skipIf(TEST_NETWORK != 'regtest', 'elementsd doesnt yet support PSBT features we need')
+def test_script_splice_out(node_factory, bitcoind):
+    l1, l2 = node_factory.line_graph(2, fundamount=1000000, wait_for_announce=True, opts={'experimental-splicing': None})
+    l1.rpc.splice("*:? -> 100000; 100%-fee -> wallet", force_feerate=True, debug_log=True)
+    p1 = only_one(l1.rpc.listpeerchannels(peer_id=l2.info['id'])['channels'])
+    p2 = only_one(l2.rpc.listpeerchannels(l1.info['id'])['channels'])
+    assert p1['inflight'][0]['splice_amount'] == -100000
+    assert p1['inflight'][0]['total_funding_msat'] == 900000000
+    assert p1['inflight'][0]['our_funding_msat'] == 1000000000
+    assert p2['inflight'][0]['splice_amount'] == 0
+    assert p2['inflight'][0]['total_funding_msat'] == 900000000
+    assert p2['inflight'][0]['our_funding_msat'] == 0
+    bitcoind.generate_block(6, wait_for_mempool=1)
+    l2.daemon.wait_for_log(r'lightningd, splice_locked clearing inflights')
+
+    p1 = only_one(l1.rpc.listpeerchannels(peer_id=l2.info['id'])['channels'])
+    p2 = only_one(l2.rpc.listpeerchannels(l1.info['id'])['channels'])
+    assert p1['to_us_msat'] == 900000000
+    assert p1['total_msat'] == 900000000
+    assert p2['to_us_msat'] == 0
+    assert p2['total_msat'] == 900000000
+    assert 'inflight' not in p1
+    assert 'inflight' not in p2
+
+
+@pytest.mark.openchannel('v1')
+@pytest.mark.openchannel('v2')
+@unittest.skipIf(TEST_NETWORK != 'regtest', 'elementsd doesnt yet support PSBT features we need')
+def test_script_splice_in(node_factory, bitcoind):
+    l1, l2 = node_factory.line_graph(2, fundamount=1000000, wait_for_announce=True, opts={'experimental-splicing': None})
+    l1.rpc.splice("wallet -> 200000; 100000 -> *:?", force_feerate=True, debug_log=True)
+    p1 = only_one(l1.rpc.listpeerchannels(peer_id=l2.info['id'])['channels'])
+    p2 = only_one(l2.rpc.listpeerchannels(l1.info['id'])['channels'])
+    assert p1['inflight'][0]['splice_amount'] == 100000
+    assert p1['inflight'][0]['total_funding_msat'] == 1100000000
+    assert p1['inflight'][0]['our_funding_msat'] == 1000000000
+    assert p2['inflight'][0]['splice_amount'] == 0
+    assert p2['inflight'][0]['total_funding_msat'] == 1100000000
+    assert p2['inflight'][0]['our_funding_msat'] == 0
+    bitcoind.generate_block(6, wait_for_mempool=1)
+    l2.daemon.wait_for_log(r'lightningd, splice_locked clearing inflights')
+
+    p1 = only_one(l1.rpc.listpeerchannels(peer_id=l2.info['id'])['channels'])
+    p2 = only_one(l2.rpc.listpeerchannels(l1.info['id'])['channels'])
+    assert p1['to_us_msat'] == 1100000000
+    assert p1['total_msat'] == 1100000000
+    assert p2['to_us_msat'] == 0
+    assert p2['total_msat'] == 1100000000
+    assert 'inflight' not in p1
+    assert 'inflight' not in p2