1		:- multifile generate/2.
2		:- multifile shrink/3.
3
4		:- use_module(library(avl)).
5
6		% Options:
7		% size:X with X the amount of elements in the tree
8
9		% random avl tree
10		generate(avl_tree(Options),Value) :-
11		is_list(Options) ,
12		generate(avl_tree(any([]),Options),Value).
13
14		generate(avl_tree(Type),Value) :-
15		generate(avl_tree(Type,[]),Value).
16
17		% avl tree with given type and options
18		generate(avl_tree(Type,Options),AVL) :-
19		(member(size:Size,Options)
20		-> Size >= 0
21		; random(1,50,Size)) ,
22		length(Value,Size),
23		maplist(generate(Type),Value),
24		findall(Key-true,member(Key,Value),Pairs),
25		list_to_avl(Pairs,AVL).
26
27		% check empty avl
28		shrink(Type,_,E) :-
29		Type =..[avl_tree|_] ,
30		empty_avl(E).
31		% remove some member
32		shrink(Type,Old,New) :-
33		Type =..[avl_tree|_] ,
34		avl_member(Key,Old),
35		avl_delete(Key,Old,_,New).