How to assert with promises?

[GabrielBarbosaGV]

Hello, all!

I would like to assert on the promise of a boolean, or, in other words, to assert on an async function returning a boolean. This, for the purpose of testing async code. This is how I am tying it, currently:

This mostly works, but leaves out the important aspect of a failed expectation within the assert callback, which would cause minimization. What happens now is that expect fails, but after assert is already done, which gives me a warning, but no indication of which input caused it. This is an example of that:

When naively trying to assert with an async callback, I get a typescript compiler error saying that this is not possible.

How may I assert with promises?

Many thanks to the contributors for this great package!

Kind regards,
Gabriel Barbosa.

[krisanselmo]

Hi !
If you want to test asynchronous functions, look at fc.asyncProperty instead of fc.property.
For reference: https://github.com/dubzzz/fast-check/blob/main/packages/fast-check/documentation/Runners.md#properties

[GabrielBarbosaGV]

Very quick - many thanks!