zenvoich/fuzz

Motoko fuzzing library

fuzz's Issues

randomAlphanumeric(30) returns a string of 31 chars

Hi Zen,

Was using this package today and strangely the randomAlphanumeric(30) is returning 31 chars.
Eg: eYuerqcSz8WPWG3kUOP1kUyVPR9jnBJ

Can you double check what might be happening?

Thanks for this lib 👍

Shuffle Buffer or Mutable Array

Hey @ZenVoich,
I implemented thisshuffle function in one of my unit tests and thought it would be a good addition to this library.
It could potentially be included as a .shuffle() method in a new FuzzBuffer module, a FuzzArrayMut module, or perhaps even both.
If you're okay with it, I could submit a PR to add this feature.

   func shuffle_buffer<A>(fuzz : Fuzz.Fuzzer, buffer : Buffer.Buffer<A>) {
       for (i in Iter.range(0, buffer.size() - 3)) {
           let j = fuzz.nat.randomRange(i + 1, buffer.size() - 1);
           let tmp = buffer.get(i);
           buffer.put(i, buffer.get(j));
           buffer.put(j, tmp);
       };
   };

The buffer-size() - 3 might be confusing but here's how the selection would look in the last iteration:
buffer -> [..., i, i + 1, buffer.size() - 1]

j could be i + 1 or buffer.size() - 1