From b6c372ab4800b8dbc9e3efb042e369c9980c607a Mon Sep 17 00:00:00 2001
From: Joe Wilm <joe@jwilm.com>
Date: Sat, 10 Dec 2016 10:14:45 -0800
Subject: [PATCH] Use checked subtraction for backspace

Some shells will send a backspace at column 0, apparently.
---
 src/term.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/term.rs b/src/term.rs
index b4ac14af..33890ad5 100644
--- a/src/term.rs
+++ b/src/term.rs
@@ -570,7 +570,9 @@ impl ansi::Handler for Term {
     #[inline]
     fn backspace(&mut self) {
         debug_println!("backspace");
-        self.cursor.col -= 1;
+        if self.cursor.col > Column(0) {
+            self.cursor.col -= 1;
+        }
     }
 
     /// Carriage return