Issue #821 - Prevent TypeError in resize()

.gitignore

@@ -13,6 +13,7 @@ npm-debug.log
 .env
 build/
 .vscode/
+.DS_Store
 
 # Directories needed for code coverage
 /coverage/

package.json

@@ -39,7 +39,7 @@
     "@types/jsdom": "^11.0.1",
     "@types/mocha": "^2.2.33",
     "@types/node": "^6.0.41",
-    "browserify": "^13.1.0",
+    "browserify": "^13.3.0",
     "chai": "3.5.0",
     "docdash": "0.4.0",
     "express": "4.13.4",

src/xterm.js

@@ -1941,6 +1941,9 @@ Terminal.prototype.resize = function(x, y) {
     ch = [this.defAttr, ' ', 1]; // does xterm use the default attr?
     i = this.buffer.lines.length;
     while (i--) {
+      if (this.buffer.lines.get(i) === undefined) {
+        this.buffer.lines.set(i, this.blankLine());
+      }
       while (this.buffer.lines.get(i).length < x) {
         this.buffer.lines.get(i).push(ch);
       }