This helps. Although the rackunit API shows a thunk, the accompanying documentation doesn't really make this idea clear. And as far as I can see, doesn't explain why. The test suite documentation does talk about using lambda definitions to delay evaluations, which makes sense given the context. However, I have to interpolate that the same thing is going on here, which is counterintuitive. Does this mean I have to teach my students about lambda definitions before I can have them use rackunit for testing? (I posted the same question in response to another kind person--I do not want to seem pedantic on the point...)
Where in the racket docs can I find that argument error raises a fail contract exception? I somehow missed it. When you say that, it now makes sense to me given the error I was seeing when I ran my test code. Thank you. George -----Original Message----- From: users-boun...@racket-lang.org [mailto:users-boun...@racket-lang.org] On Behalf Of Galler Sent: Tuesday, August 27, 2013 4:30 PM To: users@racket-lang.org Subject: Re: [racket] Help with exception raising and testing 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 ____________________ Racket Users list: http://lists.racket-lang.org/users
