Insert value into LinkedList before other value. And set iterator to point on iserted value

InsertBeforeTest.java

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;

public class InsertBeforeTest {
    private void insertBefore(int before, int val, ListIterator<Integer> iter) {
        while(iter.hasNext()) {
            Integer cur = iter.next();
            if (cur >= before) {
                iter.previous();
                iter.add(val);
                iter.previous();
                return;
            }
        }
        iter.add(val);
        iter.previous();
    }

    @Test
    public void testInsertAtStart() {
        LinkedList<Integer> xs = new LinkedList<>(List.of(1, 2, 3));
        ListIterator<Integer> iter = xs.listIterator();
        insertBefore(1, 4, iter);
        Assertions.assertFalse(iter.hasPrevious());
        Assertions.assertTrue(iter.hasNext());
        Assertions.assertEquals(4, iter.next());
        Assertions.assertEquals(List.of(4, 1, 2, 3), xs);
    }

    @Test
    public void testInsertAtMiddle() {
        LinkedList<Integer> xs = new LinkedList<>(List.of(1, 2, 3));
        ListIterator<Integer> iter = xs.listIterator();
        insertBefore(2, 4, iter);
        Assertions.assertEquals(4, iter.next());
        Assertions.assertEquals(List.of(1, 4, 2, 3), xs);
    }

    @Test
    public void testInsertAtEnd() {
        LinkedList<Integer> xs = new LinkedList<>(List.of(1, 2, 3));
        ListIterator<Integer> iter = xs.listIterator();
        insertBefore(5, 4, iter);
        Assertions.assertEquals(4, iter.next());
        Assertions.assertEquals(List.of(1, 2, 3, 4), xs);
    }
}