Greying out out-of-stock product variations (WooCommerce)

Question

[EDIT: it actually works when adding the code in functions.php and omitting the changes in code WC files. Important: it only works when ONE attribute exists. However when th

Answer 1

Just adding my answer as I hunted a long time for it and none of these were working for me. no matter what $variation->is_in_stock() would ALWAYS return true.

My solution was to modify the function by changing $variation->is_in_stock() to $variation->get_stock_quantity().

$variation->get_stock_quantity() actually returns a number that you can use which is the remaining stock. so rewrite the function based on the parameters you like, say when there are 5 left you want it marked out of stock (or 0 if you want 0 to be out of stock) the function would look like so:

add_filter( 'woocommerce_variation_is_active', 'my_jazzy_function', 10, 2 );

function my_jazzy_function( $active, $variation ) {

    $var_stock_count = $variation->get_stock_quantity();

    // if there are 5 or less, disable the variant, could always just set to 0.
    if( $var_stock_count <= 6 ) {
       return false;
    }
    else {
       return true;
    }
}