Upgrading to Magento 1.4.2.0

The latest stable version of magento, version 1.4.2.0, was released on December 8th. Upgrading Magento Community Edition always poses some problem or another, mostly due to user-customized themes and third-party extensions. However, upgrading from a vanilla 1.4.1.x install does generate one error that we’ve noticed. There was a change in the way that Wishlists are set up and the “addWishlistLink()” method has been removed from the Mage_Wishlist_Block_Link class. Those upgrading from 1.4.1.x will likely see the following error:
[text]a:5:{i:0;s:69:"Invalid method Mage_Wishlist_Block_Links::addWishlistLink(Array
(
)
)";i:1;s:2313:"#0 [internal function]: Varien_Object->__call(‘addWishlistLink’, Array)[/text]
Happily, the fix for this is very simple.
1. Open app/design/frontend/default/[your-theme]/layout/wishlist.xml
2. Find the following XML block:
[xml]



[/xml]
3. Replace it with this:
[xml]

wishlist_link
[/xml]
4. Since Magento caches all of its XML files, you need to clear the cache under System > Cache Management.
Although not strictly necessary after the above fix is in place, you can also add the following method definition to the Mage_Wishlist_Block_Links class. (NOTE: as always, it is prudent to make any code changes in the app/code/local directory tree rather than the app/code/core directory tree):
[php]public function addWishlistLink()
{
return $this;
}[/php]
And that’s all you need to do. Hopefully the rest of your upgrade proceeds smoothly.