Hamcrest v3.1

[tumbarumba]

This issue is for planning and discussion of features and fixes that will go into Hamcrest v3.1

Included:

• Derive version from git #419
• Javadoc cleanup #420
• java.util.Optional matchers #421
• Allow matching against polymorphic collections #422
• Implement matchers for thrown exceptions in Runnable #423
• Migrate all tests to JUnit Jupiter #424

Candidates:

• Clarify difference between Matchers and CoreMatchers
• Add JVM compatibility table
• Publish to Maven Central using GitHub Actions #416
• Java 8 Supporting Language Features #206
• IsUnmodifiableCollection matcher feature #249, fix for JDK 17 #381
• GraalVM Native Image support #403
• Add file content matcher to FileMatchers #345

See also:

• Hamcrest v4.0 #418

[jstewmon]

👋 I'm interested in trying out the changes from #422 in a project where the currently released generic constraints are troublesome. How do you feel about a 3.1-rc (or any qualifier) release to get some feedback on the proposed set of changes?

FWIW the generic signature changes will be breaking in my project, but I expect them to be trivial to fix.

I'm also game for trying 4.0-rc if you're leaning towards releasing #422 in 4.0.

[tumbarumba]

Thanks @jstewmon!

I'll want to avoid publishing a releasing release candidate just yet. I remember I had a breaking change when I was doing v2.1-rc1, and it broke the CI for a number of downstream projects that were just pulling the latest release, even though it was just a release candidate. However, I'll have a go at releasing a snapshot release (v3.1-SNAPSHOT). Hopefully that will give you a chance to have a play. I'll look at doing that this weekend.

[tumbarumba]

Well, that was easy. All I needed to do was run ./gradlew publishAllPublicationsToMavenRepository.

@jstewmon the snapshot jars are available at the Maven Central snapshot repository (see https://oss.sonatype.org/content/repositories/snapshots/org/hamcrest/hamcrest/3.1-SNAPSHOT/). I'd really like to hear how it works out for you.