What’s new in #JUnit 6: Key Changes and Improvements

https://medium.com/javarevisited/whats-new-in-junit-6-key-changes-and-improvements-551a84d7ed1f

btw, if you run a user group/meetup and want me to present any of my talks (on Testable Architecture, Event Sourcing, etc.) to your group (remotely or in person in the SF Bay Area), let me know!

See my Ted Talks page: https://ted.dev/talks

#Java #EventSourcing #JUnit #AssertJ

Completed my two talks at dev2next.com! (Yes, they're Ted Talks.)

I've updated my talks page with the presentation slides and links to the relevant repositories: https://ted.dev/talks/

I'll be adding additional links and resources soon!

#dev2next #Java #JUnit

I‘m really happy that the #JUnit 6.0 went out today. Thanks to the team for making it happen!
https://fosstodon.org/@junit/115292387834899951

#JUnit 6.0.0 is released!

✨ Java 17 and Kotlin 2.2 baseline
🌄 JSpecify nullability annotations
🛫 Integrated JFR support
🚟 Kotlin suspend function support
🛑 Support for cancelling test execution
⏭️ New `--fail-fast` mode for ConsoleLauncher
🧹 Removal of deprecated APIs

https://docs.junit.org/6.0.0/release-notes/

#JUnit 5.14.0 is released!

🐞 Bug fixes and enhancements since 5.13.x
✈ Deprecations along with new APIs to ease migration to JUnit 6

https://docs.junit.org/5.14.0/release-notes/

#JUnit 6.0.0-RC3 is ready for testing!

📰 Everything in 6.0.0-M1, M2, RC1, and RC2
⚠ Replacements for problematic APIs along with deprecations
🐞 Minor enhancements and bug fixes since 6.0.0-RC2

https://docs.junit.org/6.0.0-RC3/release-notes/

#JUnit 6.0.0-RC2 is ready for testing!

📰 Everything in 6.0.0-M1, 6.0.0-M2, and 6.0.0-RC1
🐞 Minor enhancements and bug fixes since 6.0.0-RC1

https://junit.org/junit5/docs/6.0.0-RC2/release-notes/

✨ New blog post: "STF Milestone 6: Improved Kotlin support"

#JUnit 6.0.0-RC1 improves JUnit's #Kotlin story by adding support for suspending functions, sequences, contracts and nullness annotations.

👉 https://marcphilipp.de/blog/2025/08/21/stf-milestone-6-improved-kotlin-support/

Thanks to the @sovtechfund for their support!

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object ImprovedKotlinSupportTests { val data = sequenceOf( // Sequence<T> support arguments(1, Month.JANUARY), arguments(12, Month.DECEMBER) ) @ParameterizedTest @FieldSource("data") // suspending function support for coroutine testing suspend fun test(value: Int, month: Month?) { assertNotNull(month) // contracts to support... assertEquals(value, month.value) // smart casts! } }

#JUnit 6.0.0-RC1 is ready for testing!

📰 Everything in 6.0.0-M1 and 6.0.0-M2
🏷 Improved display names for parameterized classes/tests
♻ `MethodOrderer.Default` and `ClassOrderer.Default` for `@Nested` classes

https://junit.org/junit5/docs/6.0.0-RC1/release-notes/

✨ New blog post: "STF Milestone 5: Discovery issues"

Ever written a test that wasn't being executed? 😱

#JUnit 5.13 introduced a mechanism for reporting such issues found during test discovery.

👉 https://marcphilipp.de/blog/2025/08/16/stf-milestone-5-discovery-issues/

Thanks to the @sovtechfund for their support!

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@Test // Java int test() { return 42; } // Not executed!!! 😱😱😱

#JUnit 6.0.0-M2 is ready for testing!

📰 Everything in 6.0.0-M1
🛑 Support for cancelling test execution
⏭️ New `--fail-fast` mode for ConsoleLauncher
🦺 Null-safe `computeIfAbsent` methods for stores
🧐 Strict evaluation of enum-based configuration parameters

https://junit.org/junit5/docs/6.0.0-M2/release-notes/

#JUnit 5.13.4 is released!

🐞 Bug fixes and minor improvements

https://junit.org/junit5/docs/5.13.4/release-notes/

#JUnit 5.13.3 is released!

🐞 Bug fixes and minor improvements

https://junit.org/junit5/docs/5.13.3/release-notes/

#JUnit 6.0.0-M1 is ready for testing!

✨ Require Java 17 and Kotlin 2.2
🌄 JSpecify nullability info
🚟 Kotlin suspend function support
🛫 Integrated custom JFR events
🚅 FastCSV-backed Csv{File}Source
🧹 Remove deprecated APIs and behaviors

https://junit.org/junit5/docs/6.0.0-M1/release-notes/

#JUnit 5.12.2 is released!

🐞 Fix regression when using CleanupMode.ON_SUCCESS

https://junit.org/junit5/docs/5.12.2/release-notes/

#PairProgramming (if you'd like to) #TDD #JUnit5 #Kotlin #Java

✨ New blog post: "STF Milestone 3: Release verification and automation"

A major goal of the @sovtechfund is to help projects become more sustainable and decrease their truck factor. For #JUnit, one activity in desperate need of improvement in this area was performing a release. Prior to this milestone, all JUnit releases of the past years had been performed from my local computer. It was high time to change that!

https://marcphilipp.de/blog/2025/04/01/stf-milestone-3-release-verification-and-automation/

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screenshot of GitHub Actions workflow chart