package com.flipper83.katapotter;

import java.util.List;

public class BasketCalculator {
    public int calculatePrice(List<String> books) {
        return -1;
    }
}

package com.flipper83.katapotter;

import java.util.List;

public class BasketCalculator {
    public int calculatePrice(List<String> books) {
        return 0;
    }
}

Test empty basket working correctly
[Green] Test empty basket working correctly
