I'm using PropEr to write my property based test. How can I see what kind of data my generator produces?
Let's say I have the following generator:
-module(my).
-include_lib("proper/include/proper.hrl").
-export([valid_type_gen/0]).
valid_type_gen() -> non_empty(list(any())).
I would like to examine what kind of data it generates, i.e. something like:
$ erl
1> my:valid_type_gen().sample() %???
[1,b,"blah"]
For the same question in Triq, look here.
The relevant function is proper_gen:pick/1
. It returns a tuple {ok, V}
.
$ erl
1> proper_gen:pick(my:valid_type_gen()).
{ok,[{{},<<>>,2},
[{},11.690292064109402,
{{}},
{},18.096053885231132,u,')[\2064Wue¢±'],
[{},-5.041761022794527,-13,
{[],-0.9553811124968509},
-5,'õ\232zc}:Ì'],
<<47,5,113,69,86,216,20,142,173,57:6>>,
'',
{2.710196163900066,0.47155396154628,{},[],
{[]},
8.42398680461108},
{[[25,
[-10.073999184421432,5.734631070941083,
{'æ\2367Ò§ü\233"',[30.925337851024143]}]],
'']},
'\031Þ\037\'\v','\214b\236']}