如何从其他Maven项目运行Maven项目的测试

Question

I have two maven projects say project1 and project2. project2 is added in the project1 dependencies due to some functional cause.

I have a unit test in project1, it is running fine when i do clean install for project1.

My requirement is, the tests in the project1 should execute when i run the project2. If the above is not possible, atleast do a clean install for project1 when i run the project2.

I cannot add project1 in the project2 dependencies, because it causes cyclic dependencies. Also i cannot add a common parent to these two projects, due to some other reasons.

Is there any way to do this? I would really appreciate if anyone can help me in this.

Here is the real situation:

project1 has a data xml say project1_xml and project2 has a data xml say project2_xml.

We need to make sure a specific part of data in both the xmls are same, if anyone comes and changes the data in only one xml and builds that project then they should see error.

So i wrote some code in project1 to parse both the xmls and return map objects. And also a unit test in project1 gets the map objects and do some comparison and throws the results.

Answer 1

Why? Project 2 is a dependency of Project 1, but Project 2 does not and should not have any idea as to whose dependency it is!

Let's look at it this way. You have a project (Project 1). As a dependency to your project, you add Hibernate (Project 2). Now when someone runs tests in Hibernate, would you expect it to run tests in your personal projects as well?

Let's say later someone creates Project 3 and then adds Project 2 as a dependency. Should Project 2 now run Project 3's tests as well?

Doesn't make sense, right? :) You have to model your dependencies appropriately.

Also if you think about it, you shouldn't even have to run your dependencies' tests. When you pull in a dependency, you are pulling in a self-contained artifact. One that you hope, has been tested before being pushed out. Those dependencies' tests would be run during their continuous integration and not during yours. Can you imagine running all the unit tests of all your dependencies in your project? It would take a very long time, right? So I would urge you to rethink the relationships between your dependencies.

If you really think that Project 1's tests should run in Project 2, and there is no way around it at all, then take a look at the code as well. Perhaps it means that both of these projects should be under different modules in a single project.

Answer 2

Hum it sounds complicated, first question: if these tests are truly unit testing, why can't you add these tests to project2 ? You should test only units of your own code, not the code of another project.

Are you familiar with multi-module maven projects ? It really helps organizing.

Answer 3

Why would you want to do that ? If you want to make sure that Project1 compiles before Project2, you must have Project2 depend on project1, and not the other way.

Answer 4

If you have cyclic dependencies like that, you have to asking the question if they really are two separate projects, or one project. Often times, someone drew an arbitrary line and separated the two projects. If they are one project, then all of the tests will run all of the time.