From ce12ff43bcfabac99c3d5067917c7152a4482c0e Mon Sep 17 00:00:00 2001
From: Jesse de Wit <witdejesse@hotmail.com>
Date: Tue, 3 Dec 2024 09:50:40 +0100
Subject: [PATCH] tramp: never create zero value htlcs

If a spendable channel balance exactly equals the amount, trampoline
payment would create a zero value htlc. Never do that!
---
 libs/gl-plugin/src/tramp.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libs/gl-plugin/src/tramp.rs b/libs/gl-plugin/src/tramp.rs
index 9b3d0b9fe..64a46b8bf 100644
--- a/libs/gl-plugin/src/tramp.rs
+++ b/libs/gl-plugin/src/tramp.rs
@@ -184,6 +184,10 @@ pub async fn trampolinepay(
     let mut acc = 0;
     let mut choosen = vec![];
     while let Some(channel) = channels.pop() {
+        if acc == amount_msat {
+            break;
+        }
+
         if (channel.spendable_msat + acc) <= amount_msat {
             choosen.push((channel.short_channel_id, channel.spendable_msat));
             acc += channel.spendable_msat;