Module QCheck.Test

Module related to individual tests. Since 0.18 most of it moved to QCheck2, and the type 'a cell was made a private implementation detail.

type res = QCheck2.Test.res =
  1. | Success
  2. | Failure
  3. | FalseAssumption
  4. | Error of exn * string
type 'a event = 'a QCheck2.Test.event =
  1. | Generating
  2. | Collecting of 'a
  3. | Testing of 'a
  4. | Shrunk of int * 'a
  5. | Shrinking of int * int * 'a
type 'a cell = 'a QCheck2.Test.cell
type 'a handler = 'a QCheck2.Test.handler
type 'a step = 'a QCheck2.Test.step
type 'a callback = 'a QCheck2.Test.callback
val fail_report : string -> 'a

Fail the test with some additional message that will be reported.

  • since 0.7
val fail_reportf : ('a, Stdlib.Format.formatter, unit, 'b) Stdlib.format4 -> 'a

Format version of fail_report

  • since 0.7
val make_cell : ?if_assumptions_fail:([ `Fatal | `Warning ] * float) -> ?count:int -> ?long_factor:int -> ?negative:bool -> ?max_gen:int -> ?max_fail:int -> ?small:('a -> int) -> ?retries:int -> ?name:string -> 'a arbitrary -> ('a -> bool) -> 'a cell

make_cell arb prop builds a test that checks property prop on instances of the generator arb.

  • parameter name

    the name of the test.

  • parameter count

    number of test cases to run, counting only the test cases which satisfy preconditions.

  • parameter retries

    number of times to retry the tested property while shrinking.

  • parameter long_factor

    the factor by which to multiply count, max_gen and max_fail when running a long test (default: 1).

  • parameter negative

    whether the test is expected not to satisfy the tested property.

  • parameter max_gen

    maximum number of times the generation function is called in total to replace inputs that do not satisfy preconditions (should be >= count).

  • parameter max_fail

    maximum number of failures before we stop generating inputs. This is useful if shrinking takes too much time.

  • parameter small

    kept for compatibility reasons; if provided, replaces the field arbitrary.small. If there is no shrinking function but there is a small function, only the smallest failures will be printed.

  • parameter if_assumptions_fail

    the minimum fraction of tests that must satisfy the precondition for a success to be considered valid. The fraction should be between 0. and 1. A warning will be emitted otherwise if the flag is `Warning, the test will be a failure if the flag is `Fatal. (since 0.10)

val get_law : 'a cell -> 'a -> bool
val get_name : _ cell -> string
val set_name : _ cell -> string -> unit
val get_count : _ cell -> int

Get the count of a cell.

  • since 0.5.3
val get_long_factor : _ cell -> int

Get the long factor of a cell.

  • since 0.5.3
val make : ?if_assumptions_fail:([ `Fatal | `Warning ] * float) -> ?count:int -> ?long_factor:int -> ?max_gen:int -> ?max_fail:int -> ?small:('a -> int) -> ?retries:int -> ?name:string -> 'a arbitrary -> ('a -> bool) -> t

make arb prop builds a test that checks property prop on instances of the generator arb. See make_cell for a description of the parameters.

val make_neg : ?if_assumptions_fail:([ `Fatal | `Warning ] * float) -> ?count:int -> ?long_factor:int -> ?max_gen:int -> ?max_fail:int -> ?small:('a -> int) -> ?retries:int -> ?name:string -> 'a arbitrary -> ('a -> bool) -> t

make_neg arb prop builds a test that checks property prop on instances of the generator arb. The test is considered negative, meaning that it is expected not to satisfy the tested property. This information is recorded in an underlying test cell entry and interpreted suitably by test runners. See make_cell for a description of the parameters.

include module type of QCheck2.Test_exceptions
exception Test_fail of string * string list

Exception raised when a test failed, with the list of counter-examples. Test_fail (name, l) means test name failed on elements of l.

exception Test_error of string * string * exn * string

Exception raised when a test raised an exception e, with the sample that triggered the exception. Test_error (name, i, e, st) means name failed on i with exception e, and st is the stacktrace (if enabled) or an empty string.

exception Test_unexpected_success of string

Exception raised when a negative test failed. Test_unexpected_success name means test name failed to find an expected counter example.

val print_instance : 'a cell -> 'a -> string
val print_c_ex : 'a cell -> 'a TestResult.counter_ex -> string
val print_fail : 'a cell -> string -> 'a TestResult.counter_ex list -> string
val print_fail_other : string -> msg:string -> string
val print_error : ?st:string -> 'a cell -> string -> ('a TestResult.counter_ex * exn) -> string
val print_test_fail : string -> string list -> string
val print_test_error : string -> string -> exn -> string -> string
val check_cell : ?long:bool -> ?call:'a callback -> ?step:'a step -> ?handler:'a handler -> ?rand:Stdlib.Random.State.t -> 'a cell -> 'a TestResult.t
val check_cell_exn : ?long:bool -> ?call:'a callback -> ?step:'a step -> ?handler:'a handler -> ?rand:Stdlib.Random.State.t -> 'a cell -> unit
val check_exn : ?long:bool -> ?rand:Stdlib.Random.State.t -> t -> unit