Check for DisplayNameGeneration annotations on runtime enclosing types

[marcphilipp]

Resolves #4131.

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Definition of Done

• There are no TODOs left in the code
• Method preconditions are checked and documented in the method's Javadoc
• Coding conventions (e.g. for logging) have been followed
• Change is covered by automated tests including corner cases, errors, and exception handling
• Public API has Javadoc and @API annotations
• Change is documented in the User Guide and Release Notes

[sbrannen]

In general the PR looks good, and the tests demonstrate the expected results. 👍

I've asked a few questions and requested a few minor changes.

Regarding the internal refactoring in DisplayNameUtils, I'll have to review that later in an IDE.

[sbrannen]

Although I certainly agree with that sentiment, developers and libraries that use AnnotationSupport often will not have access to the runtime enclosing types. Typically only JUnit internals have access to those.

So, I am a bit reluctant to deprecate this feature.

However, if we deprecate it and nobody complains, then I suppose it's fine. 😇

[marcphilipp]

Although I certainly agree with that sentiment, developers and libraries that use AnnotationSupport often will not have access to the runtime enclosing types. Typically only JUnit internals have access to those.

Jupiter extension authors can access them via ExtensionContext.getRequiredTestClass(), recursively, or get them from ExtensionContext.getRequiredTestInstances() by calling Object.getClass() on each instance.

I checked the original issue and didn't find an actual user request. Therefore, since this was the only place we used it, I deprecated the method. We can always undeprecate it if anyone complains. WDYT?

[sbrannen]

I also considered the fact that Jupiter extension authors have a way to access that information, so I was thinking more about the general purpose nature of the utilities in AnnotationSupport for other testing frameworks, engines, etc.

I checked the original issue and didn't find an actual user request. Therefore, since this was the only place we used it, I deprecated the method. We can always undeprecate it if anyone complains. WDYT?

Yep, as I mentioned before.... if nobody complains, it's fine. 👍