diff --git a/lib/ace/edit_session.js b/lib/ace/edit_session.js
index 8f772db7..cc7d72b0 100644
--- a/lib/ace/edit_session.js
+++ b/lib/ace/edit_session.js
@@ -1556,10 +1556,7 @@ var EditSession = function(text, mode) {
             // If wrapMode is activaed, the wrapData array has to be initialized.
             if (useWrapMode) {
                 var len = this.getLength();
-                this.$wrapData = [];
-                for (var i = 0; i < len; i++) {
-                    this.$wrapData.push([]);
-                }
+                this.$wrapData = Array(len);
                 this.$updateWrapData(0, len - 1);
             }
 
@@ -1719,16 +1716,10 @@ var EditSession = function(text, mode) {
 
                 lastRow = firstRow;
             } else {
-                var args;
-                if (useWrapMode) {
-                    args = [firstRow, 0];
-                    for (var i = 0; i < len; i++) args.push([]);
-                    this.$wrapData.splice.apply(this.$wrapData, args);
-                } else {
-                    args = Array(len);
-                    args.unshift(firstRow, 0);
-                    this.$rowLengthCache.splice.apply(this.$rowLengthCache, args);
-                }
+                var args = Array(len);
+                args.unshift(firstRow, 0);
+                var arr = useWrapMode ? this.$wrapData : this.$rowLengthCache
+                arr.splice.apply(arr, args);
 
                 // If some new line is added inside of a foldLine, then split
                 // the fold line up.
@@ -1833,8 +1824,7 @@ var EditSession = function(text, mode) {
                     lines[foldLine.end.row].length + 1
                 );
 
-                wrapData[foldLine.start.row]
-                    = this.$computeWrapSplits(tokens, wrapLimit, tabSize);
+                wrapData[foldLine.start.row] = this.$computeWrapSplits(tokens, wrapLimit, tabSize);
                 row = foldLine.end.row + 1;
             }
         }
@@ -2023,9 +2013,6 @@ var EditSession = function(text, mode) {
     * The first position indicates the number of columns for `str` on screen.<br/>
     * The second value contains the position of the document column that this function read until.
     *
-    *
-    *
-    *
     **/
     this.$getStringScreenWidth = function(str, maxScreenColumn, screenColumn) {
         if (maxScreenColumn == 0)
@@ -2326,14 +2313,16 @@ var EditSession = function(text, mode) {
         // Clamp textLine if in wrapMode.
         if (this.$useWrapMode) {
             var wrapRow = this.$wrapData[foldStartRow];
-            var screenRowOffset = 0;
-            while (textLine.length >= wrapRow[screenRowOffset]) {
-                screenRow ++;
-                screenRowOffset++;
+            if (wrapRow) {
+                var screenRowOffset = 0;
+                while (textLine.length >= wrapRow[screenRowOffset]) {
+                    screenRow ++;
+                    screenRowOffset++;
+                }
+                textLine = textLine.substring(
+                    wrapRow[screenRowOffset - 1] || 0, textLine.length
+                );
             }
-            textLine = textLine.substring(
-                wrapRow[screenRowOffset - 1] || 0, textLine.length
-            );
         }
 
         return {
@@ -2387,7 +2376,8 @@ var EditSession = function(text, mode) {
             var foldStart = fold ? fold.start.row :Infinity;
 
             while (row < lastRow) {
-                screenRows += this.$wrapData[row].length + 1;
+                var splits = this.$wrapData[row];
+                screenRows += splits ? splits.length + 1 : 1;
                 row ++;
                 if (row > foldStart) {
                     row = fold.end.row+1;