onchaind: see closes when wrong_funding shutdowns are used.

Fairly easy to do, though we also have to add the watch when we load
from the database.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

lightningd/channel_control.c

@@ -264,6 +264,9 @@ static void peer_got_shutdown(struct channel *channel, const u8 *msg)
 	if (!channel->shutdown_wrong_funding)
 		channel->shutdown_wrong_funding = wrong_funding;
 
+	/* We now watch the "wrong" funding, in case we spend it. */
+	channel_watch_wrong_funding(ld, channel);
+
 	/* TODO(cdecker) Selectively save updated fields to DB */
 	wallet_channel_save(ld->wallet, channel);
 }

lightningd/peer_control.c

@@ -1353,6 +1353,18 @@ static enum watch_result funding_spent(struct channel *channel,
 	return onchaind_funding_spent(channel, tx, block->height, false);
 }
 
+void channel_watch_wrong_funding(struct lightningd *ld, struct channel *channel)
+{
+	/* Watch the "wrong" funding too, in case we spend it. */
+	if (channel->shutdown_wrong_funding) {
+		/* FIXME: Remove arg from cb? */
+		watch_txo(channel, ld->topology, channel,
+			  &channel->shutdown_wrong_funding->txid,
+			  channel->shutdown_wrong_funding->n,
+			  funding_spent);
+	}
+}
+
 void channel_watch_funding(struct lightningd *ld, struct channel *channel)
 {
 	/* FIXME: Remove arg from cb? */
@@ -1361,6 +1373,7 @@ void channel_watch_funding(struct lightningd *ld, struct channel *channel)
 	watch_txo(channel, ld->topology, channel,
 		  &channel->funding_txid, channel->funding_outnum,
 		  funding_spent);
+	channel_watch_wrong_funding(ld, channel);
 }
 
 static void json_add_peer(struct lightningd *ld,

lightningd/peer_control.h

@@ -87,6 +87,8 @@ void activate_peers(struct lightningd *ld);
 void drop_to_chain(struct lightningd *ld, struct channel *channel, bool cooperative);
 
 void channel_watch_funding(struct lightningd *ld, struct channel *channel);
+/* If this channel has a "wrong funding" shutdown, watch that too. */
+void channel_watch_wrong_funding(struct lightningd *ld, struct channel *channel);
 
 struct amount_msat channel_amount_receivable(const struct channel *channel);
 

tests/test_closing.py

@@ -2738,6 +2738,5 @@ def test_shutdown_alternate_txid(node_factory, bitcoind):
     # We will see our funds return.
     assert len(l1.rpc.listfunds()['outputs']) == 1
 
-    # FIXME: we should close channels, but we don't!
-    # wait_for(lambda: l2.rpc.listpeers()['peers'] == [])
-    # wait_for(lambda: l1.rpc.listpeers()['peers'] == [])
+    wait_for(lambda: l2.rpc.listpeers()['peers'] == [])
+    wait_for(lambda: l1.rpc.listpeers()['peers'] == [])