Let's find another name for fc.set

[dubzzz]

The built-in arbitrary fc.set is able to generate arrays of unique values. Unicity is defaulted by === (might change for Object.is) and can be overriden easily by anything else.

But it has one naming issue: it does not produce Set but Array.

The aim of this discussion is to find a better name for those "arrays of unique values". I was thinking about:

• fc.uniqueArray
• fc.unique
• your ideas are more than welcomed

Renaming it would make future versions of fast-check able to re-use it for real instances of Set.

[jlink]

IMO uniqueness is an orthogonal aspect of all kinds of collections. So I’d go with some kind of fluent API, e.g. fc.array().withUniqueElements(). But I’m biased, jqwik is doing it like that: https://jqwik.net/docs/current/user-guide.html#uniqueness-constraints

[dubzzz]

Indeed a fluent API might be a really cool solution 🤔

For the moment, it has not been the choice made by fast-check but actually it was mostly to be closer to jsverify. I will definitely have to double how you did on your side and probably also check hypothesis plus others..

[dubzzz]

So far, in an attempt to stay aligned with the other existing APIs, I'll probably go for uniqueArray with PR #2616.

But fluent APIs or a array able to offer a unique feature will possibly come in the future. So far, I found it pretty handy to be able to build array of unique values with something like uniqueArray(arb) instead of array(arb, {unique: true}) or array(arb).uniqueValues() (less fast-check idiomatic than the other one).

[dubzzz]

The final choice went for uniqueArray. I'll probably re-use set for instances of Set.