Question

Imagine a multi-modules Maven project, such as the following one:

parent
  +- core
  +- main

main is dependent on the core module.

I now write a class CoreClass in core, with 2 methods: method1() and method2().
In core tests, I write a test class that will only test CoreClass.method1().

If I run a coverage tool (in my case Cobertura, using mvn sonar:sonar), I will find that I get 50% of test coverage on CoreClass (if we imagine that both methods have the same length).

Until now, everything is ok.

Now, in main project, I write a test class that will test the CoreClass.method2(). So normally, I would expect to have 100% of line coverage on CoreClass when I run an analysis on the whole project.

However, I still get my 50%.

I understand that this is a comprehensive behavior. Indeed, Cobertura will instrument CoreClass for coverage analysis only during the tests execution on the core module, and not on the main.
That explains why I still have 50% of code coverage.

However, my question is to know if there is a way to get the real code coverage of CoreClass when I am running the tests on all of my modules.

Thanks!

ps: I know that in a perfect world, it is not the concern of the main module to test the core classes. But as you may know, we are not in a perfect world :o)

Technical information: Java 1.6, JUnit 4.8.1, Maven 2.0.9 (will be upgraded to 2.2.1 soon, but I don’t think it does really matter), Sonar 2.8

Answer 1

Use jacoco and sonar and have a single jacoco.exec file result for all modules.
Sonar will use this file and report the correct coverage for each module.
I have use it for a multi module project successfully with Sonar