Maven test dependency in multi module project - maven-2

Question

I use maven to build a multi module project. My module 2 depends on Module 1 src at compile scope and module 1 tests in test scope.
Module 2 -
<dependency>
<groupId>blah</groupId>
<artifactId>MODULE1</artifactId>
<version>blah</version>
<classifier>tests</classifier>
<scope>test</scope>
</dependency>
This works fine. Say my module 3 depends on Module1 src and tests at compile time.
Module 3 -
<dependency>
<groupId>blah</groupId>
<artifactId>MODULE1</artifactId>
<version>blah</version>
<classifier>tests</classifier>
<scope>compile</scope>
</dependency>
When I run mvn clean install, my build runs till module 3, fails at module 3 as it couldn't resolve the module 1 test dependency. Then I do a mvn install on module 3 alone, go back and run mvn install on my parent pom to make it build. How can I fix this?

Answer 1

I have a doubt about what you are trying to do but but I'll assume you want to reuse the tests that you have created for a project (module1) in another. As explained in the note at the bottom of the Guide to using attached tests:
Note that previous editions of this guide suggested to use <classifier>tests</classifier> instead of <type>test-jar</type>. While this currently works for some cases, it does not properly work during a reactor build of the test JAR module and any consumer if a lifecycle phase prior to install is invoked. In such a scenario, Maven will not resolve the test JAR from the output of the reactor build but from the local/remote repository. Apparently, the JAR from the repositories could be outdated or completely missing, causing a build failure (cf. MNG-2045).
So, first, to package up compiled tests in a JAR and deploy them for general reuse, configure the maven-jar-plugin as follows:
<project>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>2.2</version>
<executions>
<execution>
<goals>
<goal>test-jar</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
Then, install/deploy the test JAR artifact as usual (using mvn install or mvn deploy).
Finally, to use the test JAR, you should specify a dependency with a specified type of test-jar:
<project>
...
<dependencies>
<dependency>
<groupId>com.myco.app</groupId>
<artifactId>foo</artifactId>
<version>1.0-SNAPSHOT</version>
<type>test-jar</type>
<scope>test</scope>
</dependency>
</dependencies>
...
</project>

Answer 2

Regarding to my comment to Pascals question i think i have found a stuitable answer :
<plugins>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<version>2.2</version>
<executions>
<execution>
<goals>
<goal>test-jar</goal>
</goals>
<phase>test-compile</phase>
</execution>
</executions>
<configuration>
<outputDirectory>${basedir}\target</outputDirectory>
</configuration>
</plugin>
</plugins>
The main difference here as you see here is the <phase> tag.
I will create the test-jar and it will be available in the compile phase of the tests and not only after the package phase.
Works for me.