Overriding/Rewrite Third Party Model in Magento 2.3 Not Working

Question

I tried to follow whatever guide there is in StackOverflow but none is working on my requirement. I want to Rewrite or Override a third party module function.

di.xml

<?xml version="1.0" ?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    <preference for="Amasty\StoreCredit\Model\History\MessageProcessor" type="Vendor\Module\Rewrite\Amasty\StoreCredit\Model\History\MessageProcessor" />
</config>

MessageProcessor.php

<?php

namespace Vendor\Module\Rewrite\Amasty\StoreCredit\Model\History;

use Magento\Framework\Option\ArrayInterface;

class MessageProcessor extends \Amasty\StoreCredit\Model\History\MessageProcessor implements ArrayInterface
{
 
    public static $actionsSmall = [
        parent::ADMIN_BALANCE_CHANGE_PLUS => 'Csh1anged By Admin',
        parent::ADMIN_BALANCE_CHANGE_MINUS => 'Cs1hanged By Admin',
        parent::CREDIT_MEMO_REFUND  => 'Refunded #%3',
        parent::ORDER_PAY => 'Order Paid #%3',
        parent::ORDER_CANCEL => 'Order Canceled #%3'
    ];

    public function __construct()
    {
        // logging to test override
        $logger = \Magento\Framework\App\ObjectManager::getInstance()->get('\Psr\Log\LoggerInterface');
        $logger->debug('Model Override Test');
    }
}

This is the original file or function that i want to override

Amasty/MessageProcessor

<?php

/**
 * @author Amasty Team
 * @copyright Copyright (c) 2019 Amasty (https://www.amasty.com)
 * @package Amasty_StoreCredit
 */

namespace Amasty\StoreCredit\Model\History;

use Magento\Framework\Option\ArrayInterface;

class MessageProcessor implements ArrayInterface
{
    /** %1 - add N store credits. %2 - new store credit balance */
    const ADMIN_BALANCE_CHANGE_PLUS = 1;
    /** %1 - remove N store credits. %2 - new store credit balance */
    const ADMIN_BALANCE_CHANGE_MINUS = 2;
    /** %1 - add N store credits. %2 - new store credit balance. %3 - order increment id */
    const CREDIT_MEMO_REFUND = 3;
    /** %1 - remove N store credits. %2 - new store credit balance. %3 - order id */
    const ORDER_PAY = 4;
    /** %1 - add N store credits. %2 - new store credit balance. %3 - order increment id */
    const ORDER_CANCEL = 5;

    /**
     * @var array
     */
    public static $actionsFull = [
        self::ADMIN_BALANCE_CHANGE_PLUS => 'Administrator added %1 store credits to your balance',
        self::ADMIN_BALANCE_CHANGE_MINUS => 'Administrator removed %1 store credits from your balance',
        self::CREDIT_MEMO_REFUND  => 'You order #%3 was refunded on %1',
        self::ORDER_PAY => 'Order #%3 was payed with %1 store credits',
        self::ORDER_CANCEL => 'Order #%3 was canceled. Returned %1 store credits',
    ];

    public static $actionsSmall = [
        self::ADMIN_BALANCE_CHANGE_PLUS => 'Changed By Admin',
        self::ADMIN_BALANCE_CHANGE_MINUS => 'Changed By Admin',
        self::CREDIT_MEMO_REFUND  => 'Refunded #%3',
        self::ORDER_PAY => 'Order Paid #%3',
        self::ORDER_CANCEL => 'Order Canceled #%3'
    ];

    /**
     * @var array
     */
    public static $actionsMail = [
        self::ADMIN_BALANCE_CHANGE_PLUS => 'Administrator adds to store credit balance',
        self::ADMIN_BALANCE_CHANGE_MINUS => 'Administrator removes from store credit balance',
        self::CREDIT_MEMO_REFUND  => 'Order refund (paid with store credit)',
        self::ORDER_PAY => 'Order place (paid with store credit)',
        self::ORDER_CANCEL => 'Order cancelation (paid with store credit)',
    ];

    public function addToI18n()
    {
        __('Administrator add %1 store credits to your balance');
        __('Administrator remove %1 store credits from your balance');
        __('You order %1 was refunded on %2');
        __('Order %1 was payed by %2 store credits');
        __('Changed By Admin');
        __('Refunded #%3');
        __('Order Paid #%3');
        __('On Administrator add store credits to balance');
        __('On Administrator remove store credits to balance');
        __('On order refund');
        __('On Order payed by store credits');
    }

    /**
     * @param int $action
     * @param array $data
     *
     * @return \Magento\Framework\Phrase|string
     */
    public static function processFull($action, array $data)
    {
        if (isset(self::$actionsFull[$action])) {
            return __(self::$actionsFull[$action], ...$data);
        }

        return '';
    }

    /**
     * @param int $action
     * @param array $data
     *
     * @return \Magento\Framework\Phrase|string
     */
    public static function processSmall($action, array $data)
    {
        if (isset(self::$actionsSmall[$action])) {
            return __(self::$actionsSmall[$action], ...$data);
        }

        return '';
    }

    /**
     * @return array
     */
    public function toOptionArray()
    {
        $optionArray = [];
        foreach ($this->toArray() as $value => $label) {
            $optionArray[] = ['value' => $value, 'label' => $label];
        }
        return $optionArray;
    }

    /**
     * Get options in "key-value" format
     *
     * @return array
     */
    public function toArray()
    {
        return self::$actionsMail;
    }
}

All i want is to change the value for this array keys ADMIN_BALANCE_CHANGE_PLUS and ADMIN_BALANCE_CHANGE_MINUS. Thank you for the help

Answer 1

I have three theories:

1. Your di.xml is incorrect, your first line is incomplete :

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

when it should be like this:

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">

2. Is your namespace really "Vendor\Module"? If so, change it for something else, your code seems correct but I'm guessing that "Vendor" and "Module" are reserved names.

3. Also did you clear your config cache? Otherwise your di.xml won't be taken into account.