Is it possible to extend the test libraries from one project into another project's test libraries? I'm creating a multiproject multiplatform project and I'm using a line like this:

implementation(project(":kgraphql"))

within jvmMain, but it's not possible to get the jvmTest from that project to it's side project. Are there any solutions for this except just copy and paste it?

This is tricky because of cyclic dependencies. I haven’t found a good way yet. Maybe add a regular non-test module and depend on it in all tests? But that would still be cyclic if it depends on your actual “base module”. I think you can also depend on specific source sets from other projects but I forgot how that works.

I've worked around this by pulling the tests into the main source of a third module, and depending on it from the other two modules test sources.

Thanks for sharing your experience with this. I think I will just copy and paste it instead of creating a fake module to solve it.

Well it’s not a fake module but a real module. Nothing bad about that and much better than copying. It’s only problematic if that test module has to depend on a module that in turn needs the test module for testing 😄

Not sure it works for multiplatform but I think

apply plugin: 'java-test-fixtures'

is what you want

You can do something like this without running into circular dependency issues