qtest 2.0.0 · OCaml Package

val (==>) : bool -> bool -> bool

b1 ==> b2 is the logical implication b1 => b2 ie not b1 || b2 (except that it is strict).

type 'a gen_print = (unit -> 'a) * ('a -> string)

a value of type 'a gen_print is a pair where the first component generates random value of type 'a and the second component can print them.

val unit : unit gen_print

always generates (), obviously.

val bool : bool gen_print

uniform boolean generator

val float : float gen_print

generates regular floats (no nan and no infinities)

val pos_float : float gen_print

positive float generator (no nan and no infinities)

val neg_float : float gen_print

negative float generator (no nan and no infinities)

val int : int gen_print

int generator. Uniformly distributed

val pos_int : int gen_print

positive int generator. Uniformly distributed

val small_int : int gen_print

positive int generator. The probability that a number is chosen is roughly an exponentially decreasing function of the number.

val neg_int : int gen_print

negative int generator. The distribution is similar to that of small_int, not of pos_int.

val char : char gen_print

Uniformly distributed on all the chars (not just ascii or valid latin-1)

val printable_char : char gen_print

uniformly distributed over a subset of chars

val numeral_char : char gen_print

uniformy distributed over '0'..'9'

val string_gen_of_size : (unit -> int) -> (unit -> char) -> string gen_print

val string_gen : (unit -> char) -> string gen_print

generates strings with a distribution of length of small_int

val string : string gen_print

generates strings with a distribution of length of small_int and distribution of characters of char

val string_of_size : (unit -> int) -> string gen_print

generates strings with distribution of characters if char

val printable_string : string gen_print

generates strings with a distribution of length of small_int and distribution of characters of printable_char

val printable_string_of_size : (unit -> int) -> string gen_print

generates strings with distribution of characters of printable_char

val numeral_string : string gen_print

generates strings with a distribution of length of small_int and distribution of characters of numeral_char

val numeral_string_of_size : (unit -> int) -> string gen_print

generates strings with a distribution of characters of numeral_char

val list : 'a gen_print -> 'a list gen_print

generates lists with length generated by small_int

val list_of_size : (unit -> int) -> 'a gen_print -> 'a list gen_print

generates lists with length from the given distribution

val array : 'a gen_print -> 'a array gen_print

generates arrays with length generated by small_int

val array_of_size : (unit -> int) -> 'a gen_print -> 'a array gen_print

generates arrays with length from the given distribution

val pair : 'a gen_print -> 'b gen_print -> ('a * 'b) gen_print

combines two generators into a generator of pairs

val triple : 
  'a gen_print ->
  'b gen_print ->
  'c gen_print ->
  ('a * 'b * 'c) gen_print

combines three generators into a generator of 3-uples

val option : 'a gen_print -> 'a option gen_print

val fun1 : 'a gen_print -> 'b gen_print -> ('a -> 'b) gen_print

generator of functions of arity 1. The functions are always pure and total functions:

when given the same argument (as decided by Pervasives.(=)), it returns the same value
it never does side effects, like printing or never raise exceptions etc. The functions generated are really printable.

val fun2 : 
  'a gen_print ->
  'b gen_print ->
  'c gen_print ->
  ('a -> 'b -> 'c) gen_print

generator of functions of arity 2. The remark about fun1 also apply here.

val laws_exn : 
  ?small:('a -> int) ->
  ?count:int ->
  string ->
  'a gen_print ->
  ('a -> bool) ->
  unit

laws_exn ?small ?count name gen law generates up to count random values of type 'a with using gen. The predicate law is called on them and if it returns false or raises an exception then we have a counter example for the law.

If small is given, then some other random values are generated and the smallest one (where compare example1 example2 is defined as Pervasives.compare (small (example1)) (small (example2))) is kept.

If small is not given, then the generations stop at the first counter example.

If a counter example has been found, then it an exception that contains the stringified example is thrown.

package qtest