Invalid taxonomy ‘product_cat’ in wc integration

Hi everybody,

I have an issue with getting product_cat terms.
I am extending WC_Integration class in order to create a small settings page in admin.

I simply want to output a select with all product categories as options where the value is ID of the term and text (between <option> and </option>) is term name.

I was unable to find woocommerce function which returns the array of product categories terms, so I used built-in WordPress function:

$product_cats = get_terms([ 'taxonomy' => 'product_cat' ]);

$product_cats_options = [];
foreach ($product_cats as $product_cat) {
    $product_cats_options[$product_cat->term_id] = $product_cat->name;
}

$this->form_fields = [
    'club_price_product_cats'   => [
                'title'         => __('Club Products', 'woocommerce'),
                'type'          => 'select',
                'description'   => __('Which product categories adopt the price from above.', 'woocommerce'),
                'options'       => $product_cats_options
            ]
];

The code above is in init_form_fields() function in my class.

The problem is get_terms() returns WP_Error object with message ‘Invalid taxonomy’. So I did var_dump(get_taxonomies()) and it doesn’t return product_cat in the list.

Some people pointed on the internet that product_cat isn’t there because it’s not registered until ‘init’ hook and my code runs before ‘init’ hook. But I don’t know how to solve the problem. I don’t call init_form_fields() myself, Woocoomerce does.

Can anybody help me with this?

Thanks.

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