How can you tell if he is in love?

if you really want to know if he truly loves you put him up to some kind of test. I know it is hard to just come out and say i love you and wait for his response and wonder if he will even say it back. i am going through the same thing wit ha girl that i love but for the past year have only been friends with. so i cant really give u a definitive answer cause i am going through the same thing but the only thing i can think of is to test him some how.