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.test.environment.Live
  import zio.clock.nanoTime
  import Assertion.isGreaterThan
  
  object MyTest extends DefaultRunnableSpec {
    def spec = suite("clock")(
      testM("time is non-zero") {
        assertM(Live.live(nanoTime))(isGreaterThan(0))
      }
    )
  }

  Definition Classes

  zio

•  package environment

  The environment package contains testable versions of all the standard ZIO environment types through the TestClock, TestConsole, TestSystem, and TestRandom modules.

  The environment package contains testable versions of all the standard ZIO environment types through the TestClock, TestConsole, TestSystem, and TestRandom modules. See the documentation on the individual modules for more detail about using each of them.

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

  import zio.test.environment._
  
  myProgram.provideLayer(testEnvironment)

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

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

  import zio.test.environment._
  
  myProgram.provideM(TestConsole.make(TestConsole.DefaultData))

  Finally, you can create a Test object that implements the test interface directly using the makeTest method. This can be useful when you want to access some testing functionality without using the environment type.

  import zio.test.environment._
  
  for {
    testRandom <- TestRandom.makeTest(TestRandom.DefaultData)
    n          <- testRandom.nextInt
  } yield n

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

  Definition Classes

  test

•  object TestConsole extends Serializable

  TestConsole provides a testable interface for programs interacting with the console by modeling input and output as reading from and writing to input and output buffers maintained by TestConsole and backed by a Ref.

  TestConsole provides a testable interface for programs interacting with the console by modeling input and output as reading from and writing to input and output buffers maintained by TestConsole and backed by a Ref.

  All calls to putStr and putStrLn using the TestConsole will write the string to the output buffer and all calls to getStrLn will take a string from the input buffer. To facilitate debugging, by default output will also be rendered to standard output. You can enable or disable this for a scope using debug, silent, or the corresponding test aspects.

  TestConsole has several methods to access and manipulate the content of these buffers including feedLines to feed strings to the input buffer that will then be returned by calls to getStrLn, output to get the content of the output buffer from calls to putStr and putStrLn, and clearInput and clearOutput to clear the respective buffers.

  Together, these functions make it easy to test programs interacting with the console.

  import zio.console._
  import zio.test.environment.TestConsole
  import zio.ZIO
  
  val sayHello = for {
    name <- getStrLn
    _    <- putStrLn("Hello, " + name + "!")
  } yield ()
  
  for {
    _ <- TestConsole.feedLines("John", "Jane", "Sally")
    _ <- ZIO.collectAll(List.fill(3)(sayHello))
    result <- TestConsole.output
  } yield result == Vector("Hello, John!\n", "Hello, Jane!\n", "Hello, Sally!\n")

  Definition Classes

  environment

• Data
• Service
• Test

zio.test.environment.TestConsole

Service