Using _atts class attribute overwrites default WordPress classes, _class doesn't

[VincentvdRee]

Like the title says. Using the attribute -> class logic fails to respect WordPress classes and overwrites them. The code example below, result's in the html structure below

wp_nav_menu([
    'theme_location' => 'primary-menu',
    'container' => false,
    'fallback_cb' => false,
    'menu_class' => 'example_class',
    'li_class_0' => 'bg-red-400',
]);

wp_nav_menu([
    'theme_location' => 'primary-menu',
    'container' => false,
    'fallback_cb' => false,
    'menu_class' => 'example_class',
    'li_atts_0' => [
        'class' => 'bg-red-400',
    ],
]);

<ul id="menu-primair-menu" class="example_class">
    <li id="menu-item-19" class="menu-item ... bg-red-400">
        <a href="/">Home</a>
    </li>
    <li id="menu-item-80" class="menu-item ... bg-red-400">
        <a href="/onze-school/">Onze school</a>
    </li>
    <li id="menu-item-17" class="menu-item ... bg-red-400">
        <a href="/werken-bij/">Werken bij</a>
    </li>
    <li id="menu-item-16" class="menu-item ... bg-red-400">
        <a href="/contact/">Contact</a>
    </li>
</ul>
<ul id="menu-primair-menu-1" class="example_class">
    <li class="bg-red-400">
        <a href="/">Home</a>
    </li>
    <li class="bg-red-400">
        <a href="/onze-school/">Onze school</a>
    </li>
    <li class="bg-red-400">
        <a href="/werken-bij/">Werken bij</a>
    </li>
    <li class="bg-red-400">
        <a href="/contact/">Contact</a>
    </li>
</ul>

I'll try to look into it later this week and attempt make a PR

[davidwebca]

Interesting 🤔 I don't remember if I did this by design to allow "overriding" / erasing the entirety of WordPress' classes with one attribute and merge them when using the other.

[davidwebca]

In the end, looking at my previous projects, it's definitely unwanted. I fixed it to avoid the overriding, but now I'm thinking that's something people could want (remove default classes to have full control over the generated element). I'll consider adding a prop "atts_override" => true|false or something like that later.