Сравнение XLF

DiffXLF

<?php

/**
 * Class DiffXLF
 */
class DiffXLF
{
    /**
     * @var array
     */
    private $first = [];

    /**
     * @var array
     */
    private $secondary = [];

    /**
     * @param $file
     *
     * @return array
     */
    private function load($file): array
    {
        $xml = new SimpleXMLElement(file_get_contents($file));

        return $this->fillKeys($xml);
    }

    /**
     * @param SimpleXMLElement $XMLElement
     *
     * @return array
     */
    private function fillKeys(SimpleXMLElement $XMLElement)
    {
        foreach ($XMLElement->file->body->children() as $item) {
            $ids[] = (string) $item->attributes()->id;
        }

        return $ids ?? [];
    }

    /**
     * @param $first
     * @param $secondary
     *
     * @return array
     */
    public function diff($first, $secondary)
    {
        $this->first = $this->load($first);
        $this->secondary = $this->load($secondary);

        return array_merge(
            array_diff($this->first, $this->secondary),
            array_diff($this->secondary, $this->first)
        );
    }
}


$diff = new DiffXLF();
$diff = $diff->diff('messages.en.xlf', 'messages.ru.xlf');