Recommend declaring annotations as api

[vlsi]

Currently, dependency-analysis-android-gradle-plugin recommends downgrading org.apiguardian:apiguardian-api from api to implementation for Apache Calcite, however, that dependency should always be on the compile classpath.

Just in case, apiguardian-api is a single-annotation dependency: https://github.com/apiguardian-team/apiguardian

Here's a case by JUnit5 jhttps://github.com/junit-team/junit5/issues/1105
Similar case by Guava google/guava#2824
Caffeine ben-manes/caffeine#300

As far as I understand, many compilers need annotation classes for proper compilation (e.g. Error Prone compiler needs annotation definition for proper verification), so projects like Guava, JUnit5, Caffeine settled on using <scope>compile</scope> for their annotations.

It looks like dependency-analysis-android-gradle-plugin should suggest upgrading annotation dependencies to api in case they are used in public-like methods/classes.

[autonomousapps]

I read through the junit discussion and it was very interesting -- thanks for linking. Have you tried to follow the (perhaps inaccurate) advice and downgrade apiguardian to implementation? And if so, what was the result? Did you see issues similar in nature to what the junit team discussed?

[autonomousapps]

I have a PR now resolving this issue. Annotations on public types will now be considered part of the ABI.