Question: I have installed free price extension, <https://pluginarchive.com/magento/rp_display_price_free> the extension collapse my configurable product price. How to debug which part of the extension affects my Magento core function.

Note: <https://snipboard.io/I2FrSH.jpg>

Thanks in advance..!

Answer: 
Couple of points would like to add here that one can not easily render string (in this case its **FREE** - system config (`displayfreeprice/general/freeprice_text`) ) into the price format which may be float or decimal in most of the cases.

Although, one workaround should resolve this issue showing **0.00** instead of its value.

You can do as follows:

1. `Open <magento-root>\app\code\local\Rp\Displayfreeprice\Helper\Productprice.php`
2. Look for the function named
`public static function currency( $price , $format=true , $includeContainer = true )`
3. Find the below statement.

`return parent::formatPrice($price, $includeContainer);`

4. Replace it with below statement.

`return parent::currency($price, $includeContainer);`

Refresh the cache and session and then open configurable product page.

I guess extension vendor FORGOT to replace the function name.
create file at root of magento with name **rewritelist.php** and run 

```
<?php
$foldersToCheck = array('app/code/local/', 'app/code/community/');
$configFiles = array();
foreach ($foldersToCheck as $folder){
    $files = glob($folder.'*/*/etc/config.xml');//get all config.xml files in the specified folder
    $configFiles = array_merge($configFiles, $files);//merge with the rest of the config files
}
$rewrites = array();//list of all rewrites

foreach ($configFiles as $file){
    $dom = new DOMDocument;
    $dom->loadXML(file_get_contents($file));
    $xpath = new DOMXPath($dom);
        $path = '//rewrite/*';//search for tags named 'rewrite'
        $text = $xpath->query($path);
        foreach ($text as $rewriteElement){
            $type = $rewriteElement->parentNode->parentNode->parentNode->tagName;//what is overwritten (model, block, helper)
            $parent = $rewriteElement->parentNode->parentNode->tagName;//module identifier that is being rewritten (core, catalog, sales, ...)
            $name = $rewriteElement->tagName;//element that is rewritten (layout, product, category, order)
            foreach ($rewriteElement->childNodes as $element){
                $rewrites[$type][$parent.'/'.$name][] = $element->textContent;//class that rewrites it
            }
        }
}
echo "<pre>";print_r($rewrites);

```