BUG: useEffectOnMount not fired when withPropsChildren hook is used

[Angel-O]

Versions

• scalajs-react version: 3.0.0-beta12
• react version: 19.0.0

Bug

Not sure if this is the intended behavior (I searched the official React docs but couldn't see any mention of this behavior)

.useEffectOnMount doesn't work when used in conjunction with the .withPropsChildren hook.

Here's a minimal reproducible example

object Bug extends App {

  val component = ScalaFnComponent
    .withHooks[Unit]
    .withPropsChildren
    .useEffectOnMount {
      Callback.log("useEffectOnMount not fired!") //  won't run ...
    }
    .render(_.propsChildren)

  ReactDOMClient
    .createRoot(document.querySelector("#app"))
    .render(component(<.div("hi there")))
}

If we remove the .withPropsChildren hook instead the effect runs

object NoBug extends App {

  val component = ScalaFnComponent
    .withHooks[Unit]
    .useEffectOnMount {
      Callback.log("useEffectOnMount is fired!") // will run
    }
    .render(_ => <.div("hi there"))

  ReactDOMClient
    .createRoot(document.querySelector("#app"))
    .render(component())
}

[japgolly]

Thanks for the report. This is now fixed but deploying a new release is blocked by #1114

[Angel-O]

hey @japgolly that's great, thanks for looking into it !

[japgolly]

no worries, v2.1.3 is released now, thanks for your patience