From 3213d168671b1ce8ba57fcc6c9726ec7a8e0fe4b Mon Sep 17 00:00:00 2001
From: Mottie <wowmotty@gmail.com>
Date: Tue, 20 Jan 2015 12:31:19 -0600
Subject: [PATCH] Core: optimize textExtraction function

Reduced comparisons & moved "simple" textExtraction before checks for textExtraction functions & using getColumnData, to further speed up processing time
---
 docs/index.html          |  8 ++++++--
 js/jquery.tablesorter.js | 27 +++++++++++++--------------
 2 files changed, 19 insertions(+), 16 deletions(-)

diff --git a/docs/index.html b/docs/index.html
index 7ef30e1d..a9818cc5 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -1555,11 +1555,15 @@ $.extend($.tablesorter.themes.jui, {
 
 			<tr id="textextraction">
 				<td><a href="#" class="permalink">textExtraction</a></td>
-				<td>String Or Function</td>
+				<td>Multiple*</td>
 				<td>&quot;basic&quot;</td>
-				<td>Defines which method is used to extract data from a table cell for sorting (<span class="version updated">v2.17.0</span>)
+				<td>Defines which method is used to extract data from a table cell for sorting (<span class="version updated">v2.18.5</span>)
 					<div class="collapsible">
 					<br>
+					* <span class="label label-info">Note</span> This option accepts multiple types (String, Object or Function); see below for further details.
+					<p></p>
+					In <span class="version updated">v2.18.5</span>, the code was further optimized. When set to <code>"basic"</code> (the default), the textExtraction code will check for data-attributes, otherwise, any other string value setting will skip the data-attribute value check; because of this change, there is a noticable lessening of initialization time in Internet Explorer.
+					<p></p>
 					In <span class="version updated">v2.17.0</span>, the <code>textExtraction</code> column can also be referenced by using a jQuery selector (e.g. class name, id or column index) that points to a table <em>header</em> cell.<br>
 					<pre class="prettyprint lang-js">textExtraction : {
     // 'jQuery thead cell selector' : function ( new method )
diff --git a/js/jquery.tablesorter.js b/js/jquery.tablesorter.js
index 2248a534..8fe18f80 100644
--- a/js/jquery.tablesorter.js
+++ b/js/jquery.tablesorter.js
@@ -180,24 +180,23 @@
 			}
 
 			function getElementText(table, node, cellIndex) {
-				if (!node) { return ""; }
-				var te, c = table.config,
-					t = c.textExtraction || '',
-					text = "";
-				if (t === "basic") {
-					// check data-attribute first
-					text = $(node).attr(c.textAttribute) || node.textContent || node.innerText || $(node).text() || "";
+				if (!node) { return ''; }
+				var te,
+					$node = $(node),
+					c = table.config,
+					t = c.textExtraction || '';
+				if (typeof(t) === 'string') {
+					// check data-attribute first when set to "basic"; don't use node.innerText - it's really slow!
+					return $.trim( (t === 'basic' ? $node.attr(c.textAttribute) || node.textContent : node.textContent ) || $node.text() || '' );
 				} else {
-					if (typeof(t) === "function") {
-						text = t(node, table, cellIndex);
+					if (typeof(t) === 'function') {
+						return $.trim( t(node, table, cellIndex) );
 					} else if (typeof (te = ts.getColumnData( table, t, cellIndex )) === 'function') {
-						text = te(node, table, cellIndex);
-					} else {
-						// previous "simple" method
-						text = node.textContent || node.innerText || $(node).text() || "";
+						return $.trim( te(node, table, cellIndex) );
 					}
 				}
-				return $.trim(text);
+				// fallback
+				return $.trim( node.textContent || $node.text() || '' );
 			}
 
 			function detectParserForColumn(table, rows, rowIndex, cellIndex) {