Type Members

1.  final case class PatienceConfig(timeout: Span = scaled(Span(150, Millis)), interval: Span = scaled(Span(15, Millis))) extends Product with Serializable

   Configuration object for asynchronous constructs, such as those provided by traits Eventually and Waiters.

   Configuration object for asynchronous constructs, such as those provided by traits Eventually and Waiters.

   The default values for the parameters are:

   Configuration Parameter	Default Value
   timeout	scaled(150 milliseconds)
   interval	scaled(15 milliseconds)

   timeout

   the maximum amount of time to wait for an asynchronous operation to complete before giving up and throwing TestFailedException.

   interval

   the amount of time to sleep between each check of the status of an asynchronous operation when polling

   Definition Classes

   AbstractPatienceConfiguration

2.  final case class Dismissals(value: Int) extends Product with Serializable

   A configuration parameter that specifies the number of dismissals to wait for before returning normally from an await call on a Waiter.

   A configuration parameter that specifies the number of dismissals to wait for before returning normally from an await call on a Waiter.

   value

   the number of dismissals for which to wait

   Exceptions thrown

   IllegalArgumentException if specified value is less than or equal to zero.

3.  class Waiter extends AnyRef

   Class that facilitates performing assertions outside the main test thread, such as assertions in callback methods that are invoked asynchronously.

   Class that facilitates performing assertions outside the main test thread, such as assertions in callback methods that are invoked asynchronously.

   To use Waiter, create an instance of it in the main test thread:

   val w = new Waiter // Do this in the main test thread
   

   At some point later, call await on the waiter:

   w.await() // Call await() from the main test thread
   

   The await call will block until it either receives a report of a failed assertion from a different thread, at which point it will complete abruptly with the same exception, or until it is dismissed by a different thread (or threads), at which point it will return normally. You can optionally specify a timeout and/or a number of dismissals to wait for. Here's an example:

   import org.scalatest.time.SpanSugar._
   
   w.await(timeout(300 millis), dismissals(2))
   

   The default value for timeout, provided via an implicit PatienceConfig parameter, is 150 milliseconds. The default value for dismissals is 1. The await method will block until either it is dismissed a sufficient number of times by other threads or an assertion fails in another thread. Thus if you just want to perform assertions in just one other thread, only that thread will be performing a dismissal, so you can use the default value of 1 for dismissals.

   Waiter contains four overloaded forms of await, two of which take an implicit PatienceConfig parameter. To change the default timeout configuration, override or hide (if you imported the members of Waiters companion object instead of mixing in the trait) patienceConfig with a new one that returns your desired configuration.

   To dismiss a waiter, you just invoke dismiss on it:

   w.dismiss() // Call this from one or more other threads
   

   You may want to put dismiss invocations in a finally clause to ensure they happen even if an exception is thrown. Otherwise if a dismissal is missed because of a thrown exception, an await call will wait until it times out.

   Finally, to perform an assertion in a different thread, you just apply the Waiter to the assertion code. Here are some examples:

   w { assert(1 + 1 === 3) }    // Can use assertions
   w { 1 + 1 should equal (3) } // Or matchers
   w { "hi".charAt(-1) }        // Any exceptions will be forwarded to await
   

   Here's a complete example:

   import org.scalatest._
   import concurrent.Waiters
   import scala.actors.Actor
   
   class ExampleSuite extends FunSuite with Matchers with Waiters {
   
     case class Message(text: String)
   
     class Publisher extends Actor {
   
       @volatile private var handle: Message => Unit = { (msg) => }
   
       def registerHandler(f: Message => Unit) {
         handle = f
       }
   
       def act() {
         var done = false
         while (!done) {
           react {
             case msg: Message => handle(msg)
             case "Exit" => done = true
           }
         }
       }
     }
   
     test("example one") {
   
       val publisher = new Publisher
       val message = new Message("hi")
       val w = new Waiter
   
       publisher.start()
   
       publisher.registerHandler { msg =>
         w { msg should equal (message) }
         w.dismiss()
       }
   
       publisher ! message
       w.await()
       publisher ! "Exit"
     }
   }