spatie / laravel-collection-macros

src/macros/after.php

<?php

use Illuminate\Support\Collection;

/*
 * Get the next item from the collection.
 *
 * @param mixed $currentItem
 * @param mixed $fallback
 *
 * @return mixed
 */
Collection::macro('after', function ($currentItem, $fallback = null) {
    $currentKey = $this->search($currentItem, true);

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    if ($currentKey === false) {
        return $fallback;
    }

    $currentOffset = $this->keys()->search($currentKey, true);

    $next = $this->slice($currentOffset, 2);

    if ($next->count() < 2) {
        return $fallback;
    }

    return $next->last();
});