From ecb19ba6f2cfe06efe4934a2b26722959838db9c Mon Sep 17 00:00:00 2001
From: niftynei <niftynei@gmail.com>
Date: Wed, 16 Feb 2022 15:16:07 -0600
Subject: [PATCH] coin_mvt: report mutual close outputs also

It's better to report every single utxo on close so we know when
to mark a channel account as definitively closed.
---
 onchaind/onchaind.c   | 31 +++++++++++++++++++++++++++++--
 tests/test_closing.py |  4 ++--
 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/onchaind/onchaind.c b/onchaind/onchaind.c
index 1a7ee7499..d210590ad 100644
--- a/onchaind/onchaind.c
+++ b/onchaind/onchaind.c
@@ -247,6 +247,31 @@ static void record_external_deposit(const struct tracked_output *out,
 	record_external_output(&out->outpoint, out->sat, blockheight, tag);
 }
 
+static void record_mutual_close(const struct tx_parts *tx,
+				const u8 *remote_scriptpubkey,
+				u32 blockheight)
+{
+	/* FIXME: if we ever change how closes happen, this will
+	 * need to be updated as there's no longer 1 output
+	 * per peer */
+	for (size_t i = 0; i < tal_count(tx->outputs); i++) {
+		struct bitcoin_outpoint out;
+
+		if (!wally_tx_output_scripteq(tx->outputs[i],
+					      remote_scriptpubkey))
+			continue;
+
+		out.n = i;
+		out.txid = tx->txid;
+		record_external_output(&out,
+				       amount_sat(tx->outputs[i]->satoshi),
+				       blockheight,
+				       TO_THEM);
+		break;
+	}
+}
+
+
 static void record_channel_deposit(struct tracked_output *out,
 				   u32 blockheight, enum mvt_tag tag)
 {
@@ -3882,9 +3907,11 @@ int main(int argc, char *argv[])
 	 * without any pending payments) and publish it on the blockchain (see
 	 * [BOLT #2: Channel Close](02-peer-protocol.md#channel-close)).
 	 */
-	if (is_mutual_close(tx, scriptpubkey[LOCAL], scriptpubkey[REMOTE]))
+	if (is_mutual_close(tx, scriptpubkey[LOCAL], scriptpubkey[REMOTE])) {
+		record_mutual_close(tx, scriptpubkey[REMOTE],
+				    tx_blockheight);
 		handle_mutual_close(outs, tx);
-	else {
+	} else {
 		/* BOLT #5:
 		 *
 		 * 2. The bad way (*unilateral close*): something goes wrong,
diff --git a/tests/test_closing.py b/tests/test_closing.py
index 2975701ac..705cac755 100644
--- a/tests/test_closing.py
+++ b/tests/test_closing.py
@@ -108,12 +108,12 @@ def test_closing_simple(node_factory, bitcoind, chainparams):
     expected_1 = {
         '0': [('wallet', ['deposit'], ['withdrawal'], 'A')],
         'A': [('wallet', ['deposit'], None, None), ('cid1', ['channel_open', 'opener'], ['channel_close'], 'B')],
-        'B': [('wallet', ['deposit'], None, None)],
+        'B': [('wallet', ['deposit'], None, None), ('external', ['to_them'], None, None)],
     }
 
     expected_2 = {
         'A': [('cid1', ['channel_open'], ['channel_close'], 'B')],
-        'B': [('wallet', ['deposit'], None, None)],
+        'B': [('wallet', ['deposit'], None, None), ('external', ['to_them'], None, None)],
     }
     tags = check_utxos_channel(l1, [channel_id], expected_1)
     check_utxos_channel(l2, [channel_id], expected_2, tags)