Module OUnitDiff

Unit tests for collection of elements

This module allows to define a more precise way to display differences between collection of elements. When collection differ, the tester is interested by what are the missing/extra elements. This module provides a diff operation to spot the difference quickly between two sets of elements.

Example:

open OUnit;;

module EInt =
struct
  type t = int
  let compare = ( - )
  let pp_printer = Format.pp_print_int
  let pp_print_sep = OUnitDiff.pp_comma_separator
end

module ListInt = OUnitDiff.ListSimpleMake(EInt);;

let test_diff () =
  ListInt.assert_equal
    [1; 2; 3; 4; 5]
    [1; 2; 5; 4]
;;

let _ =
  run_test_tt_main ("test_diff" >:: test_diff)
;;

when run this test outputs:

OUnit: expected: 1, 2, 3, 4, 5 but got: 1, 2, 5, 4
differences: element number 2 differ (3 <> 5)

Signatures

module type DIFF_ELEMENT = sig ... end

Definition of an element

module type S = sig ... end

Definition of standard operations

Implementations

module SetMake (D : DIFF_ELEMENT) : S with type e = D.t

Collection of elements based on a Set, elements order doesn't matter

module ListSimpleMake (D : DIFF_ELEMENT) : S with type e = D.t and type t = D.t list

Collection of elements based on a List, order matters but difference display is very simple. It stops at the first element which differs.

val pp_comma_separator : Stdlib.Format.formatter -> unit -> unit
module EString : DIFF_ELEMENT with type t = string
module EInt : DIFF_ELEMENT with type t = int