Magento 1 Corrigindo o Sub Total do cupom de desconto no Magento 1 - PHP 7

Se você criou um cupom de desconto e notou que o valor do desconto não é calculado corretamente ao sub total, saiba é simples resolver. Isso acontece em especial quando usamos o PHP 7 para rodar no Magento. Existe duas formas para resolver isso. A primeira é trocar o PHP no CPANEL, porém não recomendo muito, já que pode afetar outras aplicações. O segundo método é atualizar um arquivo no source, foi o que fiz e deu certo.

1. Acesse o FTP e localize: app/code/core/Mage/Sales/Model/Config/Ordered.php

2. Comente esse código
 

/**
     * Aggregate before/after information from all items and sort totals based on this data
     *
     * @return array
     */

   protected function _getSortedCollectorCodes()
    {
        if (Mage::app()->useCache('config')) {
            $cachedData = Mage::app()->loadCache($this->_collectorsCacheKey);
            if ($cachedData) {
                return unserialize($cachedData);
            }
        }
        $configArray = $this->_modelsConfig;
        // invoke simple sorting if the first element contains the "sort_order" key
        reset($configArray);
        $element = current($configArray);
        if (isset($element['sort_order'])) {
            uasort($configArray, array($this, '_compareSortOrder'));
        } else {
            foreach ($configArray as $code => $data) {
                foreach ($data['before'] as $beforeCode) {
                    if (!isset($configArray[$beforeCode])) {
                        continue;
                    }
                    $configArray[$code]['before'] = array_unique(array_merge(
                        $configArray[$code]['before'], $configArray[$beforeCode]['before']
                    ));
                    $configArray[$beforeCode]['after'] = array_merge(
                        $configArray[$beforeCode]['after'], array($code), $data['after']
                    );
                    $configArray[$beforeCode]['after'] = array_unique($configArray[$beforeCode]['after']);
                }
                foreach ($data['after'] as $afterCode) {
                    if (!isset($configArray[$afterCode])) {
                        continue;
                    }
                    $configArray[$code]['after'] = array_unique(array_merge(
                        $configArray[$code]['after'], $configArray[$afterCode]['after']
                    ));
                    $configArray[$afterCode]['before'] = array_merge(
                        $configArray[$afterCode]['before'], array($code), $data['before']
                    );
                    $configArray[$afterCode]['before'] = array_unique($configArray[$afterCode]['before']);
                }
            }
            uasort($configArray, array($this, '_compareTotals'));
        }
        $sortedCollectors = array_keys($configArray);
        if (Mage::app()->useCache('config')) {
            Mage::app()->saveCache(serialize($sortedCollectors), $this->_collectorsCacheKey, array(
                    Mage_Core_Model_Config::CACHE_TAG
                )
            );
        }
        return $sortedCollectors;
    }

3. Cole logo em seguida esse código.
 

/****
 Note: While applying coupon code, Totals are not updating due to uasort not working in php7 then
 modified the _getSortedCollectorCodes() function as shown below. 

 ****/
protected function _getSortedCollectorCodes()
{
    if (Mage::app()->useCache('config')) {
        $cachedData = Mage::app()->loadCache($this->_collectorsCacheKey);
        if ($cachedData) {
            return unserialize($cachedData);
        }
    }
    $configArray = $this->_modelsConfig;
    // invoke simple sorting if the first element contains the "sort_order" key
    reset($configArray);
    $element = current($configArray);
    Mage::log(var_export($element,true));
    if (isset($element['sort_order'])) {
        uasort($configArray, array($this, '_compareSortOrder'));
    } else {
        foreach ($configArray as $code => $data) {
            foreach ($data['before'] as $beforeCode) {
                if (!isset($configArray[$beforeCode])) {
                    continue;
                }
                $configArray[$code]['before'] = array_unique(array_merge(
                    $configArray[$code]['before'], $configArray[$beforeCode]['before']
                ));
                $configArray[$beforeCode]['after'] = array_merge(
                    $configArray[$beforeCode]['after'], array($code), $data['after']
                );
                $configArray[$beforeCode]['after'] = array_unique($configArray[$beforeCode]['after']);
            }
            foreach ($data['after'] as $afterCode) {
                if (!isset($configArray[$afterCode])) {
                    continue;
                }
                $configArray[$code]['after'] = array_unique(array_merge(
                    $configArray[$code]['after'], $configArray[$afterCode]['after']
                ));
                $configArray[$afterCode]['before'] = array_merge(
                    $configArray[$afterCode]['before'], array($code), $data['before']
                );
                $configArray[$afterCode]['before'] = array_unique($configArray[$afterCode]['before']);
            }
        }
        foreach ($configArray as $code => $data) {
           $largest_small = $smallest_large = 0;
           foreach ($data['after'] as $afterCode) {
              if(isset($configArray[$afterCode]['sort_order']) && $largest_small < $configArray[$afterCode]['sort_order'])
                 $largest_small = $configArray[$afterCode]['sort_order'];
           }
           foreach ($data['before'] as $beforeCode) {
              if(isset($configArray[$beforeCode]['sort_order']) && ($smallest_large == 0 || $configArray[$beforeCode]['sort_order'] < $smallest_large)) 
                 $smallest_large = $configArray[$beforeCode]['sort_order'];
           }
           if($smallest_large <= $largest_small+1){
              $add = $largest_small+1-$largest_small;
              if($smallest_large == 0) $smallest_large = $largest_small+1;
              foreach ($configArray as $code1 => $data1) {
                 if(!isset($data1['sort_order'])) break;
                 if($smallest_large <= $data1['sort_order'])
                    $configArray[$code1]['sort_order'] += $add;
               }
           }
           $configArray[$code]['sort_order'] = $largest_small+1;
        }
        uasort($configArray, array($this, '_compareSortOrder'));
    }
    $sortedCollectors = array_keys($configArray);
    if (Mage::app()->useCache('config')) {
        Mage::app()->saveCache(serialize($sortedCollectors), $this->_collectorsCacheKey, array(
                Mage_Core_Model_Config::CACHE_TAG
            )
        );
    }
    return $sortedCollectors;
}

4. É só salvar e enviar. Se tiver com preguiça de fazer, só baixar o arquivo anexado ao tutorial. 

Créditos ao site Stackexchange, eu apenas traduzi as instruções.

Ordered.php