Testing utop

[bartoszmodelski]

Release 0.3.0 broke utop (link). It'd be nice if we could add testing to prevent such issues slipping through in the future.

I have not found anything specifically designed for testing utop, but we could have a simple test that orchestrates utop / dune utop . through dropping to command-line.

$ cat test.ml 
let test_1 () = assert false;;

let run () = 
  match test_1 () with
  | () -> Stdlib.exit 0
  | exception _ -> Stdlib.exit 1
;;

run ()
$ utop -init test.ml 
.. 
$ echo $?
1