From 73cbc4314f7dff692e910d74c20d665141f15225 Mon Sep 17 00:00:00 2001
From: vsariola <5684185+vsariola@users.noreply.github.com>
Date: Sat, 6 Feb 2021 17:12:53 +0200
Subject: [PATCH] fix(tracker): clamp CurrentInstrument and CurrentUnit when
 song is loaded

---
 tracker/tracker.go | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/tracker/tracker.go b/tracker/tracker.go
index 09291c8..b57e0e6 100644
--- a/tracker/tracker.go
+++ b/tracker/tracker.go
@@ -82,6 +82,12 @@ func (t *Tracker) LoadSong(song sointu.Song) error {
 	defer t.songPlayMutex.Unlock()
 	t.song = song
 	t.ClampPositions()
+	if l := len(t.song.Patch.Instruments); t.CurrentInstrument >= len(t.song.Patch.Instruments) {
+		t.CurrentInstrument = l - 1
+	}
+	if l := len(t.song.Patch.Instruments[t.CurrentInstrument].Units); t.CurrentUnit >= l {
+		t.CurrentUnit = l - 1
+	}
 	if t.sequencer != nil {
 		t.sequencer.SetPatch(song.Patch)
 		t.sequencer.SetRowLength(song.SamplesPerRow())