Method addFirstTest

test/DequeHelper.java:14–23

(Deque<Object> q)

  }
  
  public static void addFirstTest(Deque<Object> q) {
    Object firstObject = new Object();
    Object lastObject = new Object();
    q.addFirst(lastObject);
    q.addFirst(firstObject);
    
    verify(q.size() == 2);
    verify(q.peekFirst() == firstObject);
    verify(q.peekLast() == lastObject);
  }
  
  public static void addLastTest(Deque<Object> q) {
    Object firstObject = new Object();