FS2 to ZStream: implicit errors are not propagated, stream hangs forever

[michalliss]

Hello,

I noticed a weird behaviour when converting FS2 stream to ZStream. It seems like errors reported using Stream.raiseError are propagated correctly to the ZStream, but errors reported implicitly make the stream hang forever. See example (uncomment one of the def run = ...:

//> using scala 3.3.4
//> using dep "dev.zio::zio::2.1.14"
//> using dep "dev.zio::zio-streams::2.1.14"
//> using dep "dev.zio::zio-interop-cats::23.1.0.3"
//> using dep "org.typelevel::cats-effect::3.5.7"
//> using dep "co.fs2::fs2-core::3.11.0"

import zio.*
import zio.stream.*
import zio.interop.catz.*
import zio.stream.interop.fs2z.*
import cats.implicits.*
import fs2.Stream

object Main extends ZIOAppDefault {
  def run = hangs
  // def run = works

  def hangs = {
    val stream =
      (Stream[Task, Int](1, 2, 3) ++ (throw new Throwable("error")))
        .toZStream()
    stream.runCollect
  }

  def works = {
    val stream = (Stream[Task, Int](1, 2, 3) ++ Stream.raiseError[Task](
      Throwable("error")
    )).toZStream()
    stream.runCollect
  }
}