Packages

Definition Classes: root

Definition Classes: root

_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

object MyTest extends ZIOSpecDefault {
  def spec = suite("clock")(
    test("time is non-zero") {
      for {
        time <- Live.live(nanoTime)
      } yield assertTrue(time >= 0L)
    }
  )
}

Definition Classes: zio

package diff

Definition Classes: test

package internal

Definition Classes: test

package laws

The laws package provides functionality for describing laws as values.

The laws package provides functionality for describing laws as values. The fundamental abstraction is a set of ZLaws[Caps, R]. These laws model the laws that instances having a capability of type Caps are expected to satisfy. A capability Caps[_] is an abstraction describing some functionality that is common across different data types and obeys certain laws. For example, we can model the capability of two values of a type being compared for equality as follows:

trait Equal[-A] {
  def equal(a1: A, a2: A): Boolean
}

Definitions of equality are expected to obey certain laws:

Reflexivity - a1 === a1
Symmetry - a1 === a2 ==> a2 === a1
Transitivity - (a1 === a2) && (a2 === a3) ==> (a1 === a3)

These laws define what the capabilities mean and ensure that it is safe to abstract across different instances with the same capability.

Using ZIO Test, we can represent these laws as values. To do so, we define each law using one of the ZLaws constructors. For example:

val transitivityLaw = ZLaws.Laws3[Equal]("transitivityLaw") {
  def apply[A: Equal](a1: A, a2: A, a3: A): TestResult =
    ???
}

We can then combine laws using the + operator:

val reflexivityLaw: = ???
val symmetryLaw:    = ???

val equalLaws = reflexivityLaw + symmetryLaw + transitivityLaw

Laws have a run method that takes a generator of values of type A and checks that those values satisfy the laws. In addition, objects can extend ZLawful to provide an even more convenient syntax for users to check that instances satisfy certain laws.

object Equal extends Lawful[Equal]

object Hash extends Lawful[Hash]

object Ord extends Lawful[Ord]

checkAllLaws(Equal + Hash + Ord)(Gen.int)

Note that capabilities compose seamlessly because of contravariance. We can combine laws describing different capabilities to construct a set of laws requiring that instances having all of the capabilities satisfy each of the laws.

Definition Classes: test

package magnolia

Definition Classes: test

package poly

Definition Classes: test

package refined

Definition Classes: test

package render

Definition Classes: test

package results

Definition Classes: test

package scalacheck

This package provides helpers to integrate *some* ScalaCheck primitives to their ZIO equivalents.

This package provides helpers to integrate *some* ScalaCheck primitives to their ZIO equivalents. Currently available helpers:

Converting ScalaCheck Generators to ZIO Generators
Asserting a ScalaCheck Prop with ZIO
Asserting a ScalaCheck Properties with ZIO

**Generators**

This functionality converts legacy ScalaCheck generators to ZIO Test generators to support upgrading to ZIO Test without having to reimplement existing generators. To use it import this module and then call toGenZIO on any existing ScalaCheck generator. For example:

import org.scalacheck.Arbitrary

import zio._
import zio.test._
import zio.test.scalacheck._

val anyInt: Gen[Any, Int] =
  Arbitrary.arbitrary[Int].toGenZIO

**Asserting ScalaCheck Prop and Properties**

This functionality generates ZIO Assertions from either ScalaCheck Prop or Properties. This helps with integrating other libraries that provide ScalaCheck properties as helpers, i.e. cats-laws.

Prop example:

import org.scalacheck.Prop
import org.scalacheck.Test.{ Parameters => ScalaCheckParameters }

import zio._
import zio.test._
import zio.test.scalacheck._

val prop: Prop = Prop.forAll { (n: Int, m: Int) =>
  n + m == m + n
}
val resultDefault: TestResult = prop.assertZIO()

val resultWithCustomizations: TestResult =
  prop.assertZIO("My Prop Name", ScalaCheckParameters.default.withMaxSize(10))

Properties example:

import org.scalacheck.{ Prop, Properties }
import org.scalacheck.Test.{ Parameters => ScalaCheckParameters }

import zio._
import zio.test._
import zio.test.scalacheck._

object MyProperties extends Properties("MyProperties") {
  property("myProp") = Prop.forAll { (n: Int, m: Int) =>
    n + m == m + n
  }
}

* val resultDefault: TestResult = MyProperties.assertZIO()

// Beware that we can't provide a custom name here, it will be
// taken from the `Properties` name parameter
val resultWithCustomizations: TestResult =
  MyProperties.assertZIO(ScalaCheckParameters.default.withMaxSize(10))

Definition Classes: test

CheckConstructorLowPriority1

CheckConstructorLowPriority2

CheckConstructorLowPriority3

Eql

Gen

PrettyPrintVersionSpecific

ProvideSomePartiallyApplied

ProvideSomeSharedPartiallyApplied

ReporterEventRenderer

SuiteConstructorLowPriority1

SuiteConstructorLowPriority2

SuiteConstructorLowPriority3

SuiteConstructorLowPriority4

TestAnnotationRenderer

TestClockPlatformSpecific

TestConfig

TestConsole

TestConstructor

TestConstructorLowPriority1

TestConstructorLowPriority2

TestConstructorLowPriority3

ZIOSpecAbstractVersionSpecific

ZIOSpecDefault

ZIOSpecVersionSpecific

Gen

Companion object Gen

final case class Gen[-R, +A](sample: ZStream[R, Nothing, Sample[R, A]]) extends Product with Serializable

A Gen[R, A] represents a generator of values of type A, which requires an environment R. Generators may be random or deterministic.

Self Type: Gen[R, A]

Linear Supertypes

Serializable, Product, Equals, AnyRef, Any

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Instance Constructors

new Gen(sample: ZStream[R, Nothing, Sample[R, A]])

Value Members

final def !=(arg0: Any): Boolean
Definition Classes
AnyRef → Any
final def ##: Int
Definition Classes
AnyRef → Any
def ++[R1 <: R, A1 >: A](that: Gen[R1, A1])(implicit trace: Trace): Gen[R1, A1]
A symbolic alias for concat.
def <*>[R1 <: R, B](that: Gen[R1, B])(implicit zippable: Zippable[A, B], trace: Trace): Gen[R1, Out]
A symbolic alias for zip.
final def ==(arg0: Any): Boolean
Definition Classes
AnyRef → Any
final def asInstanceOf[T0]: T0
Definition Classes
Any
def clone(): AnyRef
Attributes
protected[lang]
Definition Classes
AnyRef
Annotations
@throws(classOf[java.lang.CloneNotSupportedException]) @IntrinsicCandidate() @native()
def collect[B](pf: PartialFunction[A, B])(implicit trace: Trace): Gen[R, B]
Maps the values produced by this generator with the specified partial function, discarding any values the partial function is not defined at.
def concat[R1 <: R, A1 >: A](that: Gen[R1, A1])(implicit trace: Trace): Gen[R1, A1]
Concatenates the specified deterministic generator with this determinstic generator, resulting in a deterministic generator that generates the values from this generator and then the values from the specified generator.
final def eq(arg0: AnyRef): Boolean
Definition Classes
AnyRef
def filter(f: (A) => Boolean)(implicit trace: Trace): Gen[R, A]
Filters the values produced by this generator, discarding any values that do not meet the specified predicate.
Filters the values produced by this generator, discarding any values that do not meet the specified predicate. Using filter can reduce test performance, especially if many values must be discarded. It is recommended to use combinators such as map and flatMap to create generators of the desired values instead.
```
val evens: Gen[Any, Int] = Gen.int.map(_ * 2)
```
def filterNot(f: (A) => Boolean)(implicit trace: Trace): Gen[R, A]
Filters the values produced by this generator, discarding any values that meet the specified predicate.
def filterZIO[R1 <: R](f: (A) => ZIO[R1, Nothing, Boolean])(implicit trace: Trace): Gen[R1, A]
Filters the values produced by this generator, discarding any values that do not meet the specified effectual predicate.
Filters the values produced by this generator, discarding any values that do not meet the specified effectual predicate. Using filterZIO can reduce test performance, especially if many values must be discarded. It is recommended to use combinators such as map and flatMap to create generators of the desired values instead.
```
val evens: Gen[Any, Int] = Gen.int.map(_ * 2)
```
def flatMap[R1 <: R, B](f: (A) => Gen[R1, B])(implicit trace: Trace): Gen[R1, B]
def flatten[R1 <: R, B](implicit ev: <:<[A, Gen[R1, B]], trace: Trace): Gen[R1, B]
final def getClass(): Class[_ <: AnyRef]
Definition Classes
AnyRef → Any
Annotations
@IntrinsicCandidate() @native()
final def isInstanceOf[T0]: Boolean
Definition Classes
Any
def map[B](f: (A) => B)(implicit trace: Trace): Gen[R, B]
def mapZIO[R1 <: R, B](f: (A) => ZIO[R1, Nothing, B])(implicit trace: Trace): Gen[R1, B]
Maps an effectual function over a generator.
final def ne(arg0: AnyRef): Boolean
Definition Classes
AnyRef
def noShrink(implicit trace: Trace): Gen[R, A]
Discards the shrinker for this generator.
final def notify(): Unit
Definition Classes
AnyRef
Annotations
@IntrinsicCandidate() @native()
final def notifyAll(): Unit
Definition Classes
AnyRef
Annotations
@IntrinsicCandidate() @native()
def productElementNames: Iterator[String]
Definition Classes
Product
def reshrink[R1 <: R, B](f: (A) => Sample[R1, B])(implicit trace: Trace): Gen[R1, B]
Discards the shrinker for this generator and applies a new shrinker by mapping each value to a sample using the specified function.
Discards the shrinker for this generator and applies a new shrinker by mapping each value to a sample using the specified function. This is useful when the process to shrink a value is simpler than the process used to generate it.
def resize(size: Int)(implicit trace: Trace): Gen[R, A]
Sets the size parameter for this generator to the specified value.
def runCollect(implicit trace: Trace): ZIO[R, Nothing, List[A]]
Runs the generator and collects all of its values in a list.
def runCollectN(n: Int)(implicit trace: Trace): ZIO[R, Nothing, List[A]]
Repeatedly runs the generator and collects the specified number of values in a list.
def runHead(implicit trace: Trace): ZIO[R, Nothing, Option[A]]
Runs the generator returning the first value of the generator.
val sample: ZStream[R, Nothing, Sample[R, A]]
final def synchronized[T0](arg0: => T0): T0
Definition Classes
AnyRef
final def wait(arg0: Long, arg1: Int): Unit
Definition Classes
AnyRef
Annotations
@throws(classOf[java.lang.InterruptedException])
final def wait(arg0: Long): Unit
Definition Classes
AnyRef
Annotations
@throws(classOf[java.lang.InterruptedException]) @native()
final def wait(): Unit
Definition Classes
AnyRef
Annotations
@throws(classOf[java.lang.InterruptedException])
def withFilter(f: (A) => Boolean)(implicit trace: Trace): Gen[R, A]
def zip[R1 <: R, B](that: Gen[R1, B])(implicit zippable: Zippable[A, B], trace: Trace): Gen[R1, Out]
Composes this generator with the specified generator to create a cartesian product of elements.
def zipWith[R1 <: R, B, C](that: Gen[R1, B])(f: (A, B) => C)(implicit trace: Trace): Gen[R1, C]
Composes this generator with the specified generator to create a cartesian product of elements with the specified function.

Deprecated Value Members

def finalize(): Unit
Attributes
protected[lang]
Definition Classes
AnyRef
Annotations
@throws(classOf[java.lang.Throwable]) @Deprecated
Deprecated
(Since version 9)

Packages

Gen

Companion object Gen

final case class Gen[-R, +A](sample: ZStream[R, Nothing, Sample[R, A]]) extends Product with Serializable

Instance Constructors

Value Members

Deprecated Value Members

Inherited from Serializable

Inherited from Product

Inherited from Equals

Inherited from AnyRef

Inherited from Any

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Packages

Gen

Companion object Gen

final case class Gen[-R, +A](sample: ZStream[R, Nothing, Sample[R, A]]) extends Product with Serializable

Instance Constructors

Value Members

Deprecated Value Members

Inherited from Serializable

Inherited from Product

Inherited from Equals

Inherited from AnyRef

Inherited from Any

Ungrouped

Gen