df-tests: check that rbf includes overlapping inputs

tests/test_opening.py

@@ -467,3 +467,40 @@ def test_rbf_reconnect_tx_sigs(node_factory, bitcoind, chainparams):
     l1_funding_txid = only_one(only_one(l1.rpc.listpeers()['peers'])['channels'])['funding_txid']
     l2_funding_txid = only_one(only_one(l2.rpc.listpeers()['peers'])['channels'])['funding_txid']
     assert l1_funding_txid == l2_funding_txid
+
+
+@unittest.skipIf(TEST_NETWORK != 'regtest', 'elementsd doesnt yet support PSBT features we need')
+@unittest.skipIf(not EXPERIMENTAL_FEATURES, "dual-funding is experimental only")
+def test_rbf_no_overlap(node_factory, bitcoind, chainparams):
+    l1, l2 = node_factory.get_nodes(2,
+                                    opts={'dev-force-features': '+223',
+                                          'allow_warning': True})
+
+    l1.rpc.connect(l2.info['id'], 'localhost', l2.port)
+    amount = 2**24
+    chan_amount = 100000
+    bitcoind.rpc.sendtoaddress(l1.rpc.newaddr()['bech32'], amount / 10**8 + 0.01)
+    bitcoind.rpc.sendtoaddress(l1.rpc.newaddr()['bech32'], amount / 10**8 + 0.01)
+    bitcoind.generate_block(1)
+    # Wait for it to arrive.
+    wait_for(lambda: len(l1.rpc.listfunds()['outputs']) > 0)
+
+    res = l1.rpc.fundchannel(l2.info['id'], chan_amount)
+    chan_id = res['channel_id']
+
+    # Check that we're waiting for lockin
+    l1.daemon.wait_for_log(' to DUALOPEND_AWAITING_LOCKIN')
+
+    next_feerate = find_next_feerate(l1, l2)
+
+    # Initiate an RBF
+    startweight = 42 + 172  # base weight, funding output
+    initpsbt = l1.rpc.fundpsbt(chan_amount, next_feerate, startweight,
+                               min_witness_weight=110,
+                               excess_as_change=True)
+
+    # Do the bump
+    bump = l1.rpc.openchannel_bump(chan_id, chan_amount, initpsbt['psbt'])
+
+    with pytest.raises(RpcError, match='No overlapping input present.'):
+        l1.rpc.openchannel_update(chan_id, bump['psbt'])