I want to test a `ViewModel` using `BehaviorSpec`,...

# kotest

[Lukasz Kalnik]

I want to test a ViewModel using BehaviorSpec, but I want the viewmodel to be a completely new instance for every leaf test (i.e. I want every Given { When { Then be an independent test).
When using the default isolation mode (SingleInstance) is it possible to somehow reset the ViewModel for every leaf test?
Or do I have to switch to the isolation mode InstancePerTest?
I tried InstancePerLeaf and it seemed like the Given/When blocks initializations were not taken over correctly into their nested Then blocks.
InstancePerTest works correctly for me, but I wanted to take advantage of faster test execution without having to instantiate the class for every test.

[tieskedh]

Most highly not the correct way, but I cheated using:

fun <V> Spec.varBeforeTest(
    bouwer :  () -> V
) = object : ReadWriteProperty<Nothing?,V> {
    var waarde : V? = null
    init {
        beforeTest {
            waarde = bouwer()
        }
    }
    override fun getValue(thisRef: Nothing?, property: KProperty<*>): V = waarde as V

    override fun setValue(thisRef: Nothing?, property: KProperty<*>, value: V) {
        waarde = value
    }

}

[Emil Kantis]

I think this is basically asking for the same thing Leo talked about a few days ago. Would it be ok to base a PR on your code @tieskedh? If you'd like you're ofc welcome to contribute it directly yourself 🙂

[tieskedh]

@Emil Kantis haha, of course you can.
But, there might be better implementations, for example the considerations:

1. Make it lazy: delay to getter
2. Use DSL : something like awaitclose can be handy. can of course also be another function.