From 55f2016683e22686412ce3923023e63ed7bf20b1 Mon Sep 17 00:00:00 2001
From: Wez Furlong <wez@wezfurlong.org>
Date: Sun, 8 Dec 2019 17:49:27 -0800
Subject: [PATCH] fix subtraction underflow

---
 src/frontend/gui/termwindow.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/frontend/gui/termwindow.rs b/src/frontend/gui/termwindow.rs
index 8b71b0920..93e6281d4 100644
--- a/src/frontend/gui/termwindow.rs
+++ b/src/frontend/gui/termwindow.rs
@@ -1672,7 +1672,9 @@ impl TermWindow {
                     self.render_metrics.cell_size.height * line_idx as isize,
                 ),
                 Size::new(
-                    (self.dimensions.pixel_width - pixel_width_of_cells) as isize,
+                    self.dimensions
+                        .pixel_width
+                        .saturating_sub(pixel_width_of_cells) as isize,
                     self.render_metrics.cell_size.height,
                 ),
             ),