From 4cafec8a9ce8f7d9e88e4be756c19cca14ab647d Mon Sep 17 00:00:00 2001
From: Thomas Fuchs <thomas@fesch.at>
Date: Thu, 31 May 2007 22:32:25 +0000
Subject: [PATCH] Prototype: String.prototype.truncate now explicitly converts
 its return value into a string if no truncation takes place. This prevents
 possible issues with methods expecting input data that is typeof == string.

---
 CHANGELOG             | 2 ++
 src/string.js         | 2 +-
 test/unit/string.html | 3 +++
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG b/CHANGELOG
index fe6572d..531481a 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* String.prototype.truncate now explicitly converts its return value into a string if no truncation takes place. This prevents possible issues with methods expecting input data that is typeof == 'string'.  [Thomas Fuchs, Tobie Langel, Sam Stephenson]
+
 * Event.findElement behaves as expected when the element passed matches the given selector.  Closes #8395.  [Mislav Marohnić, Tobie Langel]
 
 * Element.setOpacity now calls removeAttribute on the filter style on IE if no more filters remain, which makes Cleartype work properly.  Closes #8376.  [alexdemi, Thomas Fuchs]
diff --git a/src/string.js b/src/string.js
index eb60795..d42b436 100644
--- a/src/string.js
+++ b/src/string.js
@@ -48,7 +48,7 @@ Object.extend(String.prototype, {
     length = length || 30;
     truncation = truncation === undefined ? '...' : truncation;
     return this.length > length ? 
-      this.slice(0, length - truncation.length) + truncation : this;
+      this.slice(0, length - truncation.length) + truncation : String(this);
   },
 
   strip: function() {
diff --git a/test/unit/string.html b/test/unit/string.html
index d46eec9..a1126c8 100644
--- a/test/unit/string.html
+++ b/test/unit/string.html
@@ -208,6 +208,9 @@
       assertEqual('foo boo boz foo boo boz foo...', source.truncate(0));
       assertEqual('fo...', source.truncate(5));
       assertEqual('foo b', source.truncate(5, ''));
+      
+      assert(typeof 'foo'.truncate(5) == 'string');
+      assert(typeof'foo bar baz'.truncate(5) == 'string');
     }},
     
     testStrip: function() {with(this) {