qcheck-core

Core qcheck library
Library qcheck-core
Module QCheck2 . Tree
type 'a t

A tree of random generated values, where the root contains the value used for the test, and the sub-trees contain shrunk values (as trees, to be able to shrink several times a value) used if the test fails.

val root : 'a t -> 'a

root tree returns the root value of the tree of generated values t.

val children : 'a t -> 'a t Seq.t

children tree returns the direct sub-trees of the tree of generated values t.

val pp : ?depth:int -> ( Format.formatter -> 'a -> unit ) -> Format.formatter -> 'a t -> unit

pp ?depth pp_a ppf tree pretty-prints the tree of generated values tree using the pretty-print formatter ppf. Values of type 'a will be printed using the given pretty-printer pp_a.

As a tree t can be potentially huge when fully evaluated, you can control the maximum depth the printer goes with depth.

  • None means "everything"
  • 0 means "only the root"
  • 1 means "the root and its direct shrinks"
  • 2 means "the root, its direct shrinks, and the shrinks of its shrinks"
  • etc.