From a9e1ed5a72f23a53d681eaa8a939a88e24e26cbc Mon Sep 17 00:00:00 2001
From: Daniel Imms <daimms@microsoft.com>
Date: Wed, 28 Dec 2016 03:41:12 -0800
Subject: [PATCH 1/2] Ensure ydisp does not drop below 0 in refresh

Fixes #428
Related to #385
---
 src/xterm.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/xterm.js b/src/xterm.js
index a475b75f..700beafe 100644
--- a/src/xterm.js
+++ b/src/xterm.js
@@ -1077,6 +1077,7 @@ Terminal.prototype.refresh = function(start, end, queue) {
   }
 
   for (; y <= end; y++) {
+    console.log('this.ydisp: ' + this.ydisp);
     row = y + this.ydisp;
 
     line = this.lines.get(row);
@@ -1251,7 +1252,9 @@ Terminal.prototype.scroll = function() {
     // Compensate ybase and ydisp if lines has hit the maximum buffer size
     if (this.lines.length === this.lines.maxLength) {
       this.ybase--;
-      this.ydisp--;
+      if (this.ydisp !== 0) {
+        this.ydisp--;
+      }
     }
     // Optimization: pushing is faster than splicing when they amount to the same behavior
     this.lines.push(this.blankLine());

From 5d29d4ea22b34799e6203a45d94a9d66b176df17 Mon Sep 17 00:00:00 2001
From: Daniel Imms <daimms@microsoft.com>
Date: Wed, 28 Dec 2016 03:41:48 -0800
Subject: [PATCH 2/2] Remove log

---
 src/xterm.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/xterm.js b/src/xterm.js
index 700beafe..69bbc73a 100644
--- a/src/xterm.js
+++ b/src/xterm.js
@@ -1077,7 +1077,6 @@ Terminal.prototype.refresh = function(start, end, queue) {
   }
 
   for (; y <= end; y++) {
-    console.log('this.ydisp: ' + this.ydisp);
     row = y + this.ydisp;
 
     line = this.lines.get(row);