lightningd: note whether payment secret is used or not.

This will allow nodes (with log-level=debug) to gather how many payments
are made without payment_secrets.  We need to know this so we know when
we can make them compulsory.

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

lightningd/htlc_set.c

@@ -182,10 +182,11 @@ void htlc_set_add(struct lightningd *ld,
 	}
 
 	log_debug(ld->log,
-		  "HTLC set contains %zu HTLCs, for a total of %s out of %s",
+		  "HTLC set contains %zu HTLCs, for a total of %s out of %s (%spayment_secret)",
 		  tal_count(set->htlcs),
 		  type_to_string(tmpctx, struct amount_msat, &set->so_far),
-		  type_to_string(tmpctx, struct amount_msat, &total_msat)
+		  type_to_string(tmpctx, struct amount_msat, &total_msat),
+		  payment_secret ? "" : "no "
 		);
 
 	if (amount_msat_eq(set->so_far, total_msat)) {

tests/test_pay.py

@@ -2440,6 +2440,7 @@ def test_pay_no_secret(node_factory, bitcoind):
     inv_nosecret = 'lnbcrt1u1pwue4vapp5ve584t0cv27hwmy0cx9ca8uwyqyfw9y9dm3r8vus9fv36r2l9yjsdqaw3jhxazlwpshjhmwda0hxetrwfjhgxq8pmnt9qqcqp9570xsjyykvssa6ty8fjth6f2y8h09myngad9utesttwjwclv95fz3lgd402f9e5yzpnxmkypg55rkvpg522gcz4ymsjl2w3m4jhw4jsp55m7tl'
     # This succeeds until we make secrets compulsory.
     l1.rpc.pay(inv_nosecret)
+    l2.daemon.wait_for_log(r'HTLC set contains 1 HTLCs, for a total of 100000msat out of 100000msat \(no payment_secret\)')
 
 
 @flaky
@@ -2695,12 +2696,15 @@ def test_partial_payment_timeout(node_factory, bitcoind):
 
     with pytest.raises(RpcError, match=r'WIRE_MPP_TIMEOUT'):
         l1.rpc.waitsendpay(payment_hash=inv['payment_hash'], timeout=70 + TIMEOUT // 4, partid=1)
+    l2.daemon.wait_for_log(r'HTLC set contains 1 HTLCs, for a total of 500msat out of 1000msat \(payment_secret\)')
 
     # We can still pay it normally.
     l1.rpc.sendpay(route=route, payment_hash=inv['payment_hash'], msatoshi=1000, bolt11=inv['bolt11'], payment_secret=paysecret, partid=1)
     l1.rpc.sendpay(route=route, payment_hash=inv['payment_hash'], msatoshi=1000, bolt11=inv['bolt11'], payment_secret=paysecret, partid=2)
     l1.rpc.waitsendpay(payment_hash=inv['payment_hash'], timeout=TIMEOUT, partid=1)
     l1.rpc.waitsendpay(payment_hash=inv['payment_hash'], timeout=TIMEOUT, partid=2)
+    l2.daemon.wait_for_log(r'HTLC set contains 1 HTLCs, for a total of 500msat out of 1000msat \(payment_secret\)')
+    l2.daemon.wait_for_log(r'HTLC set contains 2 HTLCs, for a total of 1000msat out of 1000msat \(payment_secret\)')
 
 
 def test_partial_payment_restart(node_factory, bitcoind):