assertions

Simple assertions library for OCaml.

Assertions are unary or binary operations that return unit on success and raise an exception on failure. Each assertion defines a custom exception; for example assert_is_none will raise an exception Assert_is_none on failure. Where possible, the assertions will try to print their argument values using the dump function from BatPervasives (included in serializer.ml).

API

• assert_true : bool -> unit
• assert_false : bool -> unit
• assert_greater : 'a -> 'a -> unit
• assert_less : 'a -> 'a -> unit
• assert_equal : ('a -> 'a -> bool) -> 'a -> 'a -> unit
• (===) : 'a -> 'a -> unit
• almost_equal : ?epsilon:float -> float -> float -> unit
• assert_not_equal : 'a -> 'a -> unit
• assert_is : 'a -> 'a -> unit
• assert_is_not : 'a -> 'a -> unit
• assert_is_none : 'a option -> unit
• assert_is_not_none : 'a option -> unit
• assert_raises : exn option -> ('a -> 'b) -> 'a -> unit
• timeout : int -> ('a -> 'b) -> 'a -> 'b

Notes:

• assert_greater and assert_less are defined using the built-in (>) and (<) functions
• (===) is just assert_equal (=)
• almost_equal uses a hard-coded floating point tolerance
• assert_raises None will catch any exception
• To call assert_raises on a function of more than one argument, use partial application (i.e. assert_raises None (List.filter (fun x -> failwith "error")) []). Alternatively, wrap the entire computation in a thunk.
• timeout is an assertion by itself, but is often useful combined with (===) or assert_raises.

Install

Via OPAM:

opam install assertions