private static void CheckRandomNulls(ListNode node, int count, int nullsPercentage) { var randomNullsCount = node.Random != null ? 0 : 1; var dataNullsCount = node.Data != null ? 0 : 1; var index = 1; while (node.Next != null && index < count) { node = node.Next; if (node.Random == null) { randomNullsCount++; } if (node.Data == null) { dataNullsCount++; } index++; } if (node.Next != null || index != count) { throw new InvalidDataException(); } var limit = TestsHelper.CalculateLimit(count, nullsPercentage); var nulls = count - limit; Assert.IsTrue(nulls == randomNullsCount); Assert.IsTrue(nulls == dataNullsCount); }