ZStream: Using timeoutFail logs an unhandled error

[jasnross]

When I add .timeoutFail to a stream I always get an unhandled error log regardless of whether the stream timed out or not.

The log is at DEBUG level by default, but it seems like it could be misleading to see this if you have debug logs enabled.

Example:

import zio._
import zio.stream._

object StreamTimeoutExample extends ZIOAppDefault {
  override val bootstrap: ZLayer[ZIOAppArgs, Any, Any] =
    Runtime.setUnhandledErrorLogLevel(LogLevel.Info)

  val stream = ZStream
    .iterate(1)(_ + 1)
    .take(5)
    .schedule(Schedule.spaced(100.millis))
    .tap(n => Console.printLine(s"Received: $n"))
    .timeoutFail(new Exception("reached timeout"))(30.seconds)

  override def run = ZIO.logDebug("Start") *> stream.runDrain
}

Expected:

No unhandled error log is emitted since the stream completed successfully

Actual:

timestamp=2024-04-22T19:20:18.607412Z level=INFO thread=#zio-fiber-16 message="Fiber zio-fiber-16 did not handle an error" cause="Exception in thread "zio-fiber-16" scala.None$: None

[jdegoes]

/bounty $75

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Attempt	Started (GMT+0)	Solution
🟢 @kpritam	May 12, 2024, 6:02:05 PM	#8852

[kpritam]

/attempt #8783

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