if want to write a custom assertions for something...

# strikt

[mkobit]

if want to write a custom assertions for something like Option<T> where it is either a Some or None type, what is the best way to rite those?
for example, would it be better to have something like

fun Assertion.Builder<Option<T>>.isSome(asserts: Assertion.Builder<T>.() -> Unit)

or is there a better way to "chain" it where it short circuits the following assertions if it a None?

fun Assertion.Builder<Option<T>>.isSome(): Assertion.Builder<T>

[sandjelkovic]

Can't you do both?

fun <T> Assertion.Builder<Option<T>>.isSome(valueAssertions: Assertion.Builder<T>.() -> Unit = {}): Assertion.Builder<T>

Should cover both cases.

If you're using Arrow Datatypes I already tried it like this for some of Datatypes, you can check it out at https://github.com/sandjelkovic/kombinator/blob/master/kombinator-spring-mvc/src/test/kotlin/com/sandjelkovic/kombinator/test/StriktExtensions.kt
It works great

[mkobit]

hah awesome, it is for arrow
thanks for the example, i didnt think of doing the chaining like you did

.isA<Some<T>>()
        .get { t }
        .and(valueAssertions)