public void EnumeratorTest() { var tree = new AvlTreeList <int>() { 1, 2, 3 }; var enumerator = tree.GetEnumerator(); var result = enumerator.MoveNext(); Assert.True(result); result = enumerator.MoveNext(); Assert.True(result); result = enumerator.MoveNext(); Assert.True(result); result = enumerator.MoveNext(); Assert.False(result); result = enumerator.MoveNext(); Assert.False(result); Assert.Throws <InvalidOperationException>(() => enumerator.Current); }