From 30863e029bd2aab76a2deaf7c255d1c58e768cda Mon Sep 17 00:00:00 2001
From: LTVA1 <87536432+LTVA1@users.noreply.github.com>
Date: Thu, 25 Jan 2024 17:42:46 +0300
Subject: [PATCH] fix song collapse bringing pattern length to zero

---
 src/gui/editing.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/gui/editing.cpp b/src/gui/editing.cpp
index 183560191..555008efd 100644
--- a/src/gui/editing.cpp
+++ b/src/gui/editing.cpp
@@ -1665,6 +1665,10 @@ void FurnaceGUI::doExpand(int multiplier, const SelectionPoint& sStart, const Se
 
 void FurnaceGUI::doCollapseSong(int divider) {
   if (divider<2) return;
+  if (e->curSubSong->patLen<divider) {
+    showError("can't collapse any further!##sged");
+    return;
+  }
   finishSelection();
 
   UndoStep us;