as in the rest why asserAll forAll are not suspend functions

Question

wasyl · Answer

There is a `forall` variant in `suspend` package so maybe you re importing wrong version

wasyl · Answer

`io kotlintest data suspend forall`

simon.vergauwen · Answer

Why separate them

simon.vergauwen · Answer

Good to know first I heard about this as a long time KotlinTest user smile

Dias · Answer

that s for data driven test right

Dias · Answer

I need generators tho

simon.vergauwen · Answer

```forAll <http Gen int|Gen int> Gen string int string gt ```

simon.vergauwen · Answer

I do property based testing with `forAll`

Dias · Answer

which is not suspendable

sam · Answer

They were not suspendable because they existed before coroutines did and we couldn t just change it after But in 4 0 because it s a major change they have become suspendable

sam · Answer

So tldr wait for 4 0 or try the beta

AJ Alt · Answer

Although I understand the elegance of making all the table tasting functions `suspend` that change means they can t be used in non suspending contexts Some large teams at Microsoft make extensive use of `forall` with a JUnit test runner `4 0 0 BETA1` is unusable for them I think we should either make `forAll` non suspending but take a suspending lambda or continue to provide both suspending and non suspending versions of the functions

sam · Answer

You can t take a suspend lamba and run it in a non suspend function I don t think

sam · Answer

Let me think about what we can do Maybe inlining is a solution

sam · Answer

Maybe just duplicating them like before is the solution

simon.vergauwen · Answer

gt You can t take a suspend lamba and run it in a non suspend function I don t think You can if you implement a basic runtime for `suspend` like Arrow Fx and KotlinX do Or you need to wrap in `IO` or `Deferred` so you can delay executing the `suspend` from a non suspend function

simon.vergauwen · Answer

I e if `forAll` becomes a DSL a nested DSL of `TestCase` that way your `suspend` is wrapped in `TestCase` and you can run them yourself later however you want

simon.vergauwen · Answer

Wouldn t something like that work

simon.vergauwen · Answer

Sounds like a very interessing design challenge grimacing

sam · Answer

I think the problem is it needs to work outside of KotlinTest kotest That s why having the suspend is a problem as junit doesn t understand it

simon.vergauwen · Answer

Yes but that is why building your own `suspend` runner would solve your problem Which is quite easy to do

simon.vergauwen · Answer

You can make `Junit` understand with an adaption layer that has a `suspend` runner no

simon.vergauwen · Answer

Whenever interpreting `TestCase` into junit

AJ Alt · Answer

It looks like ultimately all these suspend functions get called with `runBlocking` in the KotestEngine What if we changed to `forall` to work like ```fun forAll vararg rows Row testfn suspend gt Unit = runBlocking ``` That would allow you to pass in suspend functions but call `forAll` from a blocking context The behavior would stay the same as it is right now

simon.vergauwen · Answer

That would hinder accumulating them and running them in parallel no

sam · Answer

It would stop the thread that s being used yeah I guess if we allocated each test a separate thread from <http Dispatchers IO|Dispatchers IO> then it wouldn t really matter

sam · Answer

We already allocate a thread per Spec actually or at least share threads were parallelism is used

sam · Answer

I guess the downside is if you want to use a coroutine inside forAll and suspend while running something outside of it in the same test scope But what are the chances of that

simon.vergauwen · Answer

gt I guess if we allocated each test a separate thread from <http Dispatchers IO|Dispatchers IO> then it wouldn t really matter That sounds dangerous