Some Upgrades

New and Enhanced Features

• Added Action.JustTransform.description() to public API.
  See this pull request for context.

Breaking Changes

• New Action.JustTransform.description() may break binary compatibility.

Dependency Upgrades and Bug Fixes

• Upgraded to Kotlin 2.1.21
• Upgraded to JUnit Platform 1.13.1
• Upgraded to KotlinX 1.10.2

Minor Bugfix

New and Enhanced Features

• Upgraded to Kotlin 2.1.0

Breaking Changes

• The bug fix for issue 599 can
  lead to different exception types - IllegalArgumentException instead of CannotFindArbitraryException -
  for provider methods that create objects of the wrong type.

Dependency Upgrades and Bug Fixes

• Fixed bug reported in issue 599
  by making return type matching for provider methods loose again.

JqwikSession Enhancements

New and Enhanced Features

• Introduced API to handle random seeds outside jqwik's lifecycle.
  See issue 581.

  • Added JqwikSession.getRandom()
  • Added JqwikSession.start(String randomSeed)
  • Added JqwikSession.run(String randomSeed, Runnable runnable)

Breaking Changes

No breaking changes

Dependency Upgrades and Bug Fixes

• Upgrade to Gradle 8.10.2
• Upgraded to JUnit Platform 1.11.1
• Upgraded to KotlinX 1.9.0

Kotlin 2.0 and Nullability Annotations

New and Enhanced Features

• Upgraded to Kotlin 2.0.0

• Upgraded to JUnit Platform 1.10.3

Breaking Changes

• StatisticsCoverage.checkQuery(Predicate<? super List<?>> query):
  query is now of type Predicate<? super List<?>> instead of Predicate<? super List<Object>>.

• Nullability annotations have been added to many API methods and interfaces.
  This could lead to compile-time warnings or errors in your code if you are using tool chains that validate those.

• UniqueElements.by() now requires a Class<? extends Function<? extends @Nullable Object, ?>>
  instead of a Class<? extends Function<?, Object>>.

Bug Fixes

• Tools like CheckerFramework did not play well with jqwik's (wrong) usage of @Nullable on type variables.
  This has been fixed. See issue 575 for details.
  Thanks to vlsi for working out all the nitty, gritty details!

• Fixed type matching bug as revealed in this comment

Bug Fix

New and Enhanced Features

• Upgraded to Kotlin 1.9.24

Bug Fixes

• Fixed bug that led to duplicate lifecycle invocations under inheritance.
  See issue 562.

Some Kotlin Care

New and Enhanced Features

• Kotlin module: Added anyForSubtypeOf<MyInterface>().
  Many thanks to jibidus for the contribution!

• Upgraded to Kotlin 1.9.23

Breaking Changes

No breaking changes

Bug Fixes

• Fixed bug in Kotlin module that let Java properties fail.
  See issue 557.

Platform Upgrade and a few Fixes

New and Enhanced Features

• Upgraded to KotlinX 1.8.0

• Upgraded to JUnit Platform 1.10.2

• Upgraded to Kotlin 1.9.22

Breaking Changes

No breaking changes

Bug Fixes

• Shrinking of strings with uniqueChars() constraint did not work properly.
  See issue 541.

• Fixed integer generation bug with uniform distribution.
  See issue 544:

Important Fixes for Java >= 18

New and Enhanced Features

• Upgraded to JUnit Platform 1.10.0

Breaking Changes

No breaking changes

Bug Fixes

• Nested test containers using @Group have not been working properly with JDK >= 18.
  Now they do. See issue 528.

• Fixed stack overflow exception while shrinking.
  See issue 526.

• Fixed out of memory error while shrinking.
  See issue 527.
  Many thanks to Juhan Oskar Hennoste for providing a fix.

Just Fixing Bugs

New and Enhanced Features

No new features

Breaking Changes

No breaking changes

Bug Fixes

• Fixed bug when using Combinators.combine() on empty list of arbitraries.
  See issue 522.

• Fixed type resolution bug.
  See issue 519.

Consolidate and Move Kotlin forward

New and Enhanced Features

• Upgraded to KotlinX 1.7.3

• Upgraded to JUnit Platform 1.10.0

• Upgraded to Kotlin 1.9.10

• Added StringArbitrary.uniqueChars() to generate strings with unique characters.
  Discussion in issue 506.
  This is an experimental feature.

• Added constraint annotation @UniqueChars for String parameters.
  This is an experimental feature.

• Added Arbitraries.fromGeneratorWithSize(..).
  See issue 494.
  This is an experimental feature.

• The Kotlin module got a brand new Combinator DSL.

• Configurators that are based on ArbitraryConfiguratorBase will now consider
  any public method the name of which starts with configure as a configuration method candidate.
  This allows heterogeneous arbitrary configurators
  that differ in arbitrary type only.

• Multiple @CharRange annotations are now also possible for @ForAll char parameters.

• EXPERIMENTAL APIs promoted to MAINTAINED:

  • Arbitrary.edgeCases(Consumer<EdgeCases.Config<T>> configurator)
  • Arbitrary.withoutEdgeCases()
  • @Property.edgeCases()
  • @ForAll.supplier()
  • @From.supplier()
  • @Provide.ignoreExceptions()
  • Combinator[2-8].filter(..)
  • ListCombinator.filter(..)
  • NumericalArbitrary.withDistribution(..)
  • TraverseArbitrary
  • TypeArbitrary.enableRecursion()
  • @UseType.enableRecursion()
  • DomainContext.getReportingFormats()
  • JqwikSession

Breaking Changes

• Configurators that are based on ArbitraryConfiguratorBase must mark their
  configure() methods as public.
  Private and package-scope methods are no longer supported considered as
  configuration method candidates.

• TypeUsage.canBeAssignedTo(TypeUsage) behaves now closer to the Java compiler's rules
  about allowing assignments - including co- and contravariance.
  This has the potential to break domains, arbitrary providers, and lifecycle hooks
  that depend on the old, more loose, behaviour.

• @Provide methods are now matched more strictly, based on assignability of returned arbitrary type.
  That means that potential mismatches of generated values and the corresponding @ForAll
  parameters will show up already at property setup time through a CannotFindArbitraryException.

• StringArbitrary.repeatChars(0.0) will now redirect to StringArbitrary.uniqueChars().
  Previously it used to just make the probability of repeating characters very low.
  See discussion in issue 506.

• Removed deprecated method TypeArbitrary.use(Executable).

• Removed deprecated methods ActionChainArbitrary.addAction(action)
  and ActionChainArbitrary.addAction(weight, action).

Bug Fixes

• Fixed bug when selecting parameterized values from domain contexts.
  See issue 499.

• Fixed type variable resolution bug.
  See issue 492.

• Fixed bug where presence of Kotlin module could mess up annotations
  of parameters in Java classes.