Two issues: 1: wrap the function-under-test in a thunk
2. check for exception type, here exn:fail:contract? which is raised by raise-argument-error. the more general exn:fail? would also work. (require rackunit) (test-exn "negative coin" exn:fail:contract? (λ _ (sum-coins -1 3 5 7) )) ____________________ Racket Users list: http://lists.racket-lang.org/users
