// New
public function patricks_enable_free_shipping( $is_available ) {

global $woocommerce;
$IsEligibleONE = False;
$IsEligibleALL = False;
$eligibleCount = 0;
$Count = 0;
// set the shipping classes that are eligible
$eligibleALL = array( 'free-shipping-all' );
$eligibleONE = array( 'free-shipping' );

// get cart contents
$cart_items = $woocommerce->cart->get_cart();

// loop through the items checking to make sure they all have the right class
foreach ( $cart_items as $key => $item ) {
    $Count = $Count + 1;
//echo “[Loop ” . $count;

    if ( ! in_array( $item['data']->get_shipping_class(), $eligibleONE ) ) {
    echo "Not Eligible ONE -";
        if ( ! in_array( $item['data']->get_shipping_class(), $eligibleALL ) ) {
        //  echo “Not Eligible ALL]”;
        }
        else {
        $IsEligibleALL = True;
        $eligibleCount = $eligibleCount + 1;
        //  echo “Eligible ALL: Count ” . $eligibleCount . “]”;
        }
    }
    //Is eligible for single-item Free Shipping
    else {
        $eligibleCount = $eligibleCount + 1;
        $IsEligibleONE = True;
        //  echo “Eligible ONE: Count ” . $eligibleCount . “]”;
    }
}
if ($eligibleCount == 0 ) {
    //echo “ENTIRE CART NOT ELIGIBLE–“;
    //echo “Eligible Count:” . $eligibleCount ;
    return false;
}

If ($IsEligibleALL == True) {
    //echo “END ALL–Eligible for ALL Count:” . $eligibleCount ;
    return $is_available;
}
elseIf ($IsEligibleONE == True && $Count == 1) {
    //echo “END ONE–Eligible for Single Count:” . $eligibleCount ;
    return $is_available;
}
else {
    //echo “END ONE–Single Not Eligible Since Count > 1 : Count” . $Count ;
    return false;
}
}