New instrumented Jar approach causes tests to test non-production code

[hurricup]

If you have a default project set up, like project with main and test roots, gradle sets tests dependency on main classes. Not instrumented jar.

Meaning, that in runtime tests will test non-instrumented code and may miss at least nullability issues.
Also, if you have tests for forms created with legacy forms creator, they will just fail, because of missing setupUI method.

Probably there is a way to tell gradle to use instrumented jar instead of main output, but I could not find one.
Even if I add instrumented jar dependency to the testRuntime, it comes after non-instrumented classes in the resulting classpath and classloader will still resolve to these non-instrumented classes.

The only way to solve this I could imagine is to move tests to separate project and specify dependencies explicitly. But this feels really bad.

[hurricup]

Created tests. Cross-project dependencies are ok, because they are manual and to instrumented jar. And in-project deps are failing.

[hurricup]

The only viable solution for now is to extract some core module and make following structure for the plugin:

plugin
\ tests
\ plugin:core
 \ main

This way we may specify test runtime dependencies for tests as project(':plugin:core', 'instrumentedJar')
You may also need to set up fat jar generation.
See commits from: Camelcade/Perl5-IDEA#2620