MAGENTO: Getting fatal error after overriding a module using my custom module

Question

I am newbie in Magento, so I need your help in finding a solution.

I am overriding one module file: app\code\core\Mage\Sales\Model\Quote\item.php

config.xml sample code:

<global>
    <models>
        <sales>
            <rewrite>
                <quote_item>Module_Name_Model_Sales_Quote_Item</quote_item>
            </rewrite>
      </sales>
   </models>
</global>

---

My item.php file contain only the class name which extend the class that i need to override:

class Module_Name_Model_Sales_Model_Quote_Item extends Mage_Sales_Model_Quote_Item 
{

}

---

Even i have not yet override any method in item.php am getting the following error when i open my website in a browser.

Fatal error: Call to a member function getCollection() on a non-object in C:\Sites\porcani\branches\development\app\code\core\Mage\Sales\Model\Quote.php on line 706

Anyone have an idea why this is happening and how to solve it? Thanks in Advance.

Answer 1

Try writing Item.php instead of item.php (capital I) for the filename.

Answer 2

You declared your class with the name Module_Name_Model_Sales_Model_Quote_Item but in the config file you have

<quote_item>Module_Name_Model_Sales_Quote_Item</quote_item>

In your class name you have an extra _Model.