From 1b4ab856c9b9fdfe79a2e97685fe6816db68bf9a Mon Sep 17 00:00:00 2001
From: Travis Ralston <travpc@gmail.com>
Date: Wed, 15 Jan 2020 21:05:00 -0700
Subject: [PATCH] Assume the position is at the end when the offset has no last
 part

We get an NPE when the user cuts their entire message, and this fixes it.
---
 src/editor/position.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/editor/position.js b/src/editor/position.js
index 4693f629998..726377ef483 100644
--- a/src/editor/position.js
+++ b/src/editor/position.js
@@ -117,7 +117,7 @@ export default class DocumentPosition {
         }
         offset += this.offset;
         const lastPart = model.parts[this.index];
-        const atEnd = offset >= lastPart.text.length;
+        const atEnd = !lastPart || offset >= lastPart.text.length; // if no last part, we're at the end
         return new DocumentOffset(offset, atEnd);
     }