run maven tests from classpath

Question

In order to clean up something of a giant mess, I set out to put the code of my tests all in one ordinary java project (all in src/main/java), and then declare that as a <scope>test</scope> dependency in another project, and expect the tests to run.

No such luck. surefire wants to just run the tests that it can see in the sources.

I can see a sadly obvious solution here involving the build-helper-plugin and adding the tests into the test compilation environment as a source directory, but I was hoping to avoid it.

In case anyone is wondering, the reason for all this is that the POM configuration for use of the failsafe plugin to run some integration tests got so complex that I wanted to split out the compiling of the test classes from the running of the tests.

Answer 1

This is now possible with Maven Surefire v2.15. Simply add the following kind of configuration to the surefire plugin:

<build>
  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>2.15</version>
    <configuration>
      <dependenciesToScan>
        <dependency>com.group.id:my-artifact</dependency>
        <dependency>com.group.id:my-other-artifact</dependency>
      </dependenciesToScan>
      ...
    </configuration>
    ...
  </plugin>
  ...
</build>

You should also declare the actual dependencies in the dependencies section:

<dependencies>
  <dependency>
    <groupId>com.group.id</groupId>
    <artifactId>my-artifact</artifactId>
    <type>test-jar</type>
    <version>1.1</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>com.group.id</groupId>
    <artifactId>my-other-artifact</artifactId>
    <type>test-jar</type>
    <version>1.1</version>
    <scope>test</scope>
  </dependency>
</dependencies>

Answer 2

No such luck. surefire wants to just run the tests that it can see in the sources.

This is currently not possible out of the box, surefire just looks at classes in target/test-classes:

• Re: Surefire not picking up tests from test-jar
• Re: maven-surefire-plugin: run unit tests from classes in a jar, not a directory

This is actually logged as SUREFIRE-569 - There should be a way to run unit tests from a dependency jar.

I can see a sadly obvious solution here involving the build-helper-plugin and adding the tests into the test compilation environment as a source directory, but I was hoping to avoid it.

The current workaround is to use dependency:unpack to unpack the jar into target/test-classes before the test phase.