From a7e415974aff9717258a5720977a1efb303327aa Mon Sep 17 00:00:00 2001
From: apricot2012 <haotiangong@hotmail.com>
Date: Thu, 25 Mar 2021 02:29:25 -0700
Subject: [PATCH] Fix Issue with Shift Selecting Across Staffs

Assert enforces ending staffidx to be higher than starting staffidx. This code reverses the two indexes if they don't satisfy idx2 >= idx1.
---
 src/libmscore/score.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/libmscore/score.cpp b/src/libmscore/score.cpp
index 6d4e611041..10a2f20d84 100644
--- a/src/libmscore/score.cpp
+++ b/src/libmscore/score.cpp
@@ -3407,6 +3407,12 @@ void Score::selectRange(Element* e, int staffIdx)
         if (selectedElement && e->type() == selectedElement->type()) {
             int idx1 = selectedElement->staffIdx();
             int idx2 = e->staffIdx();
+            if (idx2 < idx1) {
+                int temp = idx1;
+                idx1 = idx2;
+                idx2 = temp;
+            }
+
             if (idx1 >= 0 && idx2 >= 0) {
                 Fraction t1 = selectedElement->tick();
                 Fraction t2 = e->tick();