Packages

  • package root
    Definition Classes
    root
  • package zio
    Definition Classes
    root
  • package test

    _ZIO Test_ is a featherweight testing library for effectful programs.

    _ZIO Test_ is a featherweight testing library for effectful programs.

    The library imagines every spec as an ordinary immutable value, providing tremendous potential for composition. Thanks to tight integration with ZIO, specs can use resources (including those requiring disposal), have well- defined linear and parallel semantics, and can benefit from a host of ZIO combinators.

    import zio.test._
import zio.clock.nanoTime
import Assertion.isGreaterThan

object MyTest extends DefaultRunnableSpec {
  suite("clock") {
    testM("time is non-zero") {
      assertM(nanoTime, isGreaterThan(0))
    }
  }
}
    Definition Classes
    zio
  • package mock

    The mock package contains testable versions of all the standard ZIO environment types through the MockClock, MockConsole, MockSystem, and MockRandom modules.

    The mock package contains testable versions of all the standard ZIO environment types through the MockClock, MockConsole, MockSystem, and MockRandom modules. See the documentation on the individual modules for more detail about using each of them.

    If you are using ZIO Test and extending DefaultRunnableSpec a MockEnvironment containing all of them will be automatically provided to each of your tests. Otherwise, the easiest way to use the mocking functionality in ZIO Test is by providing the MockEnvironment to your program.

    import zio.test.mock._

myProgram.provideManaged(mockEnvironmentManaged)

    Then all environmental effects, such as printing to the console or generating random numbers, will be implemented by the MockEnvironment and will be fully testable. When you do need to access the "live" environment, for example to print debugging information to the close, just use the live combinator along with the effect as your normally would.

    If you are only interested in one of the mocking modules for your application, you can also access them a la carte through the make method on each module. Each mock module requires some data on initialization. Default data is included for each as DefaultData.

    import zio.test.mock._

myProgram.provideM(MockConsole.make(MockConsole.DefaultData))

    Finally, you can create a Mock object that implements the mock interface directly using the makeMock method. This can be useful when you want to access some mocking functionality without using the environment type.

    import zio.test.mock._

for {
  mockRandom <- MockRandom.makeMock(MockRandom.DefaultData)
  n          <- mockRandom.nextInt
} yield n

    This can also be useful when you are creating a more complex environment to provide the implementation for mock services that you mix in.

    Definition Classes
    test
  • Live
  • MockClock
  • MockConsole
  • MockEnvironment
  • MockRandom
  • MockSystem

trait MockClock extends Clock with Scheduler

MockClock makes it easy to deterministically and efficiently test effects involving the passage of time.

Instead of waiting for actual time to pass, sleep and methods implemented in terms of it schedule effects to take place at a given clock time. Users can adjust the clock time using the adjust and setTime methods, and all effects scheduled to take place on or before that time will automically be run.

For example, here is how we can test ZIO.timeout using MockClock:

import zio.ZIO
import zio.duration._
import zio.test.mock.MockClock

for {
  fiber  <- ZIO.sleep(5.minutes).timeout(1.minute).fork
  _      <- MockClock.adjust(1.minute)
  result <- fiber.join
} yield result == None

Note how we forked the fiber that sleep was invoked on. Calls to sleep and methods derived from it will semantically block until the time is set to on or after the time they are scheduled to run. If we didn't fork the fiber on which we called sleep we would never get to set the the time on the line below. Thus, a useful pattern when using MockClock is to fork the effect being tested, then adjust the clock to the desired time, and finally verify that the expected effects have been performed.

Sleep and related combinators schedule events to occur at a specified duration in the future relative to the current fiber time (e.g. 10 seconds from the current fiber time). The fiber time is backed by a FiberRef and is incremented for the duration each fiber is sleeping. Child fibers inherit the fiber time of their parent so methods that rely on repeated sleep calls work as you would expect.

For example, here is how we can test an effect that recurs with a fixed delay:

import zio.Queue
import zio.duration._
import zio.test.mock.MockClock

for {
  q <- Queue.unbounded[Unit]
  _ <- (q.offer(()).delay(60.minutes)).forever.fork
  a <- q.poll.map(_.isEmpty)
  _ <- MockClock.adjust(60.minutes)
  b <- q.take.as(true)
  c <- q.poll.map(_.isEmpty)
  _ <- MockClock.adjust(60.minutes)
  d <- q.take.as(true)
  e <- q.poll.map(_.isEmpty)
} yield a && b && c && d && e

Here we verify that no effect is performed before the recurrence period, that an effect is performed after the recurrence period, and that the effect is performed exactly once. The key thing to note here is that after each recurrence the next recurrence is scheduled to occur at the appropriate time in the future, so when we adjust the clock by 60 minutes exactly one value is placed in the queue, and when we adjust the clock by another 60 minutes exactly one more value is placed in the queue.

Linear Supertypes
Scheduler, Clock, Serializable, Serializable, AnyRef, Any
Known Subclasses
MockEnvironment
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. MockClock
  2. Scheduler
  3. Clock
  4. Serializable
  5. Serializable
  6. AnyRef
  7. Any
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Visibility
  1. Public
  2. All

Abstract Value Members

  1. abstract val clock: Service[Any]
    Definition Classes
    MockClock → Clock
  2. abstract val scheduler: Service[Any]
    Definition Classes
    MockClock → Scheduler

Concrete Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  5. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  6. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  7. def equals(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  8. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  9. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  10. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  11. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  12. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  13. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  14. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  15. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  16. def toString(): String
    Definition Classes
    AnyRef → Any
  17. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  18. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  19. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()

Inherited from Scheduler

Inherited from Clock

Inherited from Serializable

Inherited from Serializable

Inherited from AnyRef

Inherited from Any

Ungrouped