ZIOInterrupt_v2.scala

import zio.blocking._
import zio.duration._
import zio.{ZIO, console}

object ZIOInterrupt extends App {

  val runtime = zio.Runtime.default

  val t1 = effectBlockingInterrupt {
    try {
      println(s"t1 evaluating on ${Thread.currentThread()}")
      Thread.sleep(200) // 1. Interrupt here
      println("t1 finished")
      "t1"
    } catch {
      case e: InterruptedException => Console.err.println(s"t1 interrupted on ${Thread.currentThread()}"); throw e
    }
  }

  val t2 = t1.flatMap { x =>
    try {
      println(s"inner begin evaluating on ${Thread.currentThread()}")
      Thread.sleep(200) // 2. Interrupt here
      println("inner after sleep")
      effectBlockingInterrupt {
        try {
          println(s"inner Task begin evaluating on ${Thread.currentThread()}")
          Thread.sleep(200) // 3. Interrupt here
          println("inner Task after sleep")
          s"t2($x)"
        } catch {
          case e: InterruptedException => Console.err.println(s"t2 inner task interrupted on ${Thread.currentThread()}"); throw e
        }
      }
    } catch {
      case e: InterruptedException => Console.err.println(s"t1 interrupted on ${Thread.currentThread()}"); throw e
    }
  }

  //    val interruptAfter = 100.milliseconds  // Does not interrupt on 1. -- see below
  //  val interruptAfter = 300.milliseconds // 2. Does not interrupt on 2. -- see below
  val interruptAfter = 500.milliseconds // 3. Does not interrupt on 3. -- see below

  val f2 = runtime.unsafeRunToFuture(t2)
  Thread.sleep(interruptAfter.toMillis)
  f2.cancel()

  println("===============================================")

  val g = for {
    x <- t2.fork
    _ <- console.putStrLn(s"main loop: evaluating on ${Thread.currentThread()}")
    _ <- ZIO.sleep(interruptAfter) >>> x.interrupt
    r <- x.join
  } yield r

  runtime.unsafeRun(g)
}

/*
Results:

1.
t1 evaluating on Thread[zio-default-blocking-2-712974096,5,zio-default-blocking]
t1 interrupted on Thread[zio-default-blocking-2-712974096,5,zio-default-blocking]
===============================================
t1 evaluating on Thread[zio-default-blocking-1-712974096,5,zio-default-blocking]
main loop: evaluating on Thread[main,5,main]
t1 finished
inner begin evaluating on Thread[zio-default-async-5-205721196,5,zio-default-async]
inner after sleep
Exception in thread "main" zio.FiberFailure: Fiber failed.
An interrupt was produced by #3.
No ZIO Trace available.

2.
t1 evaluating on Thread[zio-default-blocking-2-712974096,5,zio-default-blocking]
t1 interrupted on Thread[zio-default-blocking-2-712974096,5,zio-default-blocking]
===============================================
t1 evaluating on Thread[zio-default-blocking-1-712974096,5,zio-default-blocking]
main loop: evaluating on Thread[main,5,main]
t1 finished
inner begin evaluating on Thread[zio-default-async-4-205721196,5,zio-default-async]
inner after sleep
Exception in thread "main" zio.FiberFailure: Fiber failed.
An interrupt was produced by #3.
No ZIO Trace available.

3.
t1 evaluating on Thread[zio-default-blocking-2-712974096,5,zio-default-blocking]
t1 finished
inner begin evaluating on Thread[zio-default-async-1-205721196,5,zio-default-async]
inner after sleep
===============================================
t1 evaluating on Thread[zio-default-blocking-2-712974096,5,zio-default-blocking]
main loop: evaluating on Thread[main,5,main]
t1 finished
inner begin evaluating on Thread[zio-default-async-4-205721196,5,zio-default-async]
inner after sleep
inner Task begin evaluating on Thread[zio-default-blocking-2-712974096,5,zio-default-blocking]
inner Task after sleep
Exception in thread "main" zio.FiberFailure: Fiber failed.
An interrupt was produced by #3.
No ZIO Trace available.

*/