[Vala] Second argument not sent to List sort function

[David Ma <dmlh02 gmail com>]

The second argument of a CompareFunc List sorting function does not seem to get 
sent to the function at all. For integer sorting, 0 is sent; for object sorting, 
null is sent.

For example, in the following code, the output from sort_function always says 
that item 2 is 0 when in fact it should never be 0. And the list is not sorted 
correctly.


public class Main
{
  public static void main (string[] args)
  {
    var list = new List<int>();
    list.append(3);
    list.append(2);
    list.append(1);
    list.append(4);
    
    foreach (int i in list)
        print ("list item = " + i.to_string() + "\n");
        
    list.sort((CompareFunc) sort_function);
    
    foreach (int i in list)
        print ("list item = " + i.to_string() + "\n");
  }
  
  public int sort_function(int item1, int item2) {
  
        print ("item 1 is " + item1.to_string () 
            + " and item 2 is " + item2.to_string () + "\n" );
        
        if (item1 < item2)
                return -1;
        if (item1 == item2)
                return 0;
        return 1;
  }
}


Example output is:


list item = 3
list item = 2
list item = 1
list item = 4
item 1 is 4 and item 2 is 0
item 1 is 2 and item 2 is 0
item 1 is 4 and item 2 is 0
item 1 is 1 and item 2 is 0
list item = 4
list item = 1
list item = 2
list item = 3