Hi,

I'm trying to create a mockup module to replace a network module when doing
testing.

The application consists of basically 3 parts. Some user interaction. This
calls some logic of the application, and the logic module might need to
call some other functions over the network. For testing I want to make a
mockup of the network module, in addition to synthesize the user
interaction. I want to test the logic module. The application has the
following files:

net_lib.ml:
let util_fun a = a
let foo a b = a + b
let bar a b = a - b

logic.ml:
let state = ref 0
let get_state () = !state
let do_op a b =
  incr state;
  (Net_lib.foo a b) * (Net_lib.bar (Net_lib.util_fun a) b )

main_appl.ml:
let () =
  let a, b  = Scanf.scanf  "%d %d\n" (fun a b -> a,b) in
  Printf.printf "Foo %d %d\n%!" (Logic.get_state ()) (Logic.do_op a b)

let () =
  let a, b  = Scanf.scanf  "%d %d\n" (fun a b -> a,b) in
  Printf.printf "Foo %d %d\n%!" (Logic.get_state ()) (Logic.do_op a b)


For testing I have the following modules:
net_lib_mockup.ml
include Net_lib
let foo a b = 1
let bar a b = 1

logic_mockup.ml:
module Net_lib = Net_lib_mockup
include Logic

main_test.ml:
module Logic = Logic_mockup

let () =
  let a, b = (1, 1) in
  Printf.printf "Test %d %d\n%!" (Logic.get_state ()) (Logic.do_op a b)

let () =
  let a, b = (10, 1) in
  Printf.printf "Test %d %d\n%!" (Logic.get_state ()) (Logic.do_op a b)

The problem is that the "include Logic" has already 'bound' the functions
in Logic to the Net_lib module and will not use the Net_lib_mockup that I
try to use through a moudle alias. If i replace the 'include Logic' with
the actual content of the logic.ml file, then the functions get bound to
the Logic_mockup functions, and the test works as they should.

Are there some trick to get the 'include Logic', in logic_mockup.ml, to use
to the Net_lib_mockup module and not the Net_lib module, so that I don't
have to do copy and paste between the two files?


Regards,

Hans Ole Rafaelsen