I have a mock class with a trivial implementation of a service I provide from a module. I'm using OpenJDK 11.03, gradle 5.2.1 and IntelliJ 2019.2.
In /main/code/myPackage/myService.java I have:
package myPackage;
class myService {
public abstract void someFunction();
}
And in my test/code/somePackage/myMockService I have
package myPackage;
// no import, they're in the same package.
class myMockService extends myService {
@Override
public void someFunction() { System.out.prinln("Hello World"); }
}
In my main/code/module-info.java I have
module myModule {
exports somePackage;
}
I've tried several variations on a test/code/module-info.java, without success. For example:
// "open module" lets anyone use reflection within (mostly JUnit 5 in my case)
import myPackage.myService;
import myPackage.myMockService;
open module myTestModule {
exports myPackage;
provides myService with myMockService
}
The above module-info spews errors about how "module name myTestModule does not match expected name myModule", "package 'myPackage' is not visible" (from myMockModule.java), explaining "package myPackage is declared in module myModule but module myTestModule does not read it"
On the other hand, with the following module-info, I get a different batch of errors (below the code)
import myPackage.myService;
import myPackage.myMockService;
open module myModule {
provides myService with myMockService;
}
Without a requires myModule;, every reference to the main code branch from my test code gives an "error: cannot find symbol". With a requires myModule;, I get an "error: cyclic dependence involving myModule".
So... my tests can't be in a different module. AND they can't be the same module! [long string of expletives deleted]
How do I introduce a mock version of a service in test code rather than creating an entirely different module/gradle sub-project?
Or is this simply a case where that's not possible, and while you can have a separate test module-info, you can't do much with it?
Or is there some way to dynamically load things at runtime such that I don't have to put every little mock service in any module-info, test or otherwise? Such that ServiceLoader.load will find them. Hmm... perhaps extend ServiceLoader and wrap its usage in main code such that it'll use the right one either in production code or test code...
