System.Linq.Tests.JoinTests.InnerNull C# (CSharp) Method

        public void InnerNull()
        {
            CustomerRec[] outer = new []
            {
                new CustomerRec{ name = "Prakash", custID = 98022 },
                new CustomerRec{ name = "Tim", custID = 99021 },
                new CustomerRec{ name = "Robert", custID = 99022 }
            };
            IQueryable<AnagramRec> inner = null;

            Assert.Throws<ArgumentNullException>("inner", () => outer.AsQueryable().Join(inner, e => e.name, e => e.name, (cr, or) => new JoinRec { name = cr.name, orderID = or.orderID, total = or.total }, new AnagramEqualityComparer()));
        }