diff --git a/src/base/single/tip/tip.tooltip.js b/src/base/single/tip/tip.tooltip.js
index 5499f05ac..70c710497 100644
--- a/src/base/single/tip/tip.tooltip.js
+++ b/src/base/single/tip/tip.tooltip.js
@@ -8,7 +8,7 @@
 BI.Tooltip = BI.inherit(BI.Tip, {
     _const: {
         hgap: 8,
-        vgap: 4
+        vgap: 4,
     },
 
     _defaultConfig: function () {
@@ -23,12 +23,12 @@ BI.Tooltip = BI.inherit(BI.Tip, {
     },
 
     render: function () {
-        var self = this, o = this.options;
+        var o = this.options;
         this.element.addClass("tooltip-" + o.level);
-        var fn = function (e) {
+        function fn(e) {
             o.stopPropagation && e.stopPropagation();
             o.stopEvent && e.stopEvent();
-        };
+        }
         this.element.bind({
             click: fn,
             mousedown: fn,
@@ -36,7 +36,7 @@ BI.Tooltip = BI.inherit(BI.Tip, {
             mouseover: fn,
             mouseenter: fn,
             mouseleave: fn,
-            mousemove: fn
+            mousemove: fn,
         });
 
         var texts = (o.text + "").split("\n");
@@ -52,9 +52,9 @@ BI.Tooltip = BI.inherit(BI.Tip, {
                         textAlign: o.textAlign,
                         whiteSpace: "normal",
                         text: text,
-                        textHeight: 18
+                        textHeight: 18,
                     };
-                })
+                }),
             });
         } else {
             this.text = BI.createWidget({
@@ -81,7 +81,7 @@ BI.Tooltip = BI.inherit(BI.Tip, {
     setLevel: function (level) {
         this.element.removeClass("tooltip-success").removeClass("tooltip-warning");
         this.element.addClass("tooltip-" + level);
-    }
+    },
 });
 
 BI.shortcut("bi.tooltip", BI.Tooltip);