rvesse / source-plugin-breaks-releases

Reproducer for MSOURCES-140/MSOURCES-141/MSOURCES-143 bug

What is this?

This is a minimal, reproducible example of a bug related to certain usages of the maven-sources-plugin which is tracked by several JIRA issues:

• MSOURCES-140
• MSOURCES-141
• MSOURCES-143

Basically if your build fails with the following message:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-source-plugin:3.3.0:jar-no-fork (attach-sources) on project source-plugin-breaks-releases: Presumably you have configured maven-source-plugn to execute twice times in your build. You have to configure a classifier for at least on of them. -> [Help 1]

Then you have hit some variant of this bug.

This repository particularly focuses on reproducing the bug when trying to perform a Maven release.

How do I reproduce the bug from this repository?

Just clone the code then try the following:

$ mvn release:perform

What causes this bug?

This particular instance of the bug is caused be the interaction of two things:

1. The new duplicate invocation check within the maven-source-plugin that was added as of their 3.3.0 release
2. The maven-release-plugin's usage of the implicit release profile that includes an extra invocation of the maven-source-plugin that leads to the duplicate invocation check failing

Is there a workaround?

There are some known workarounds at this time:

1. Rollback to using maven-source-plugin versions prior to 3.3.0 e.g. 3.2.1 was the last release without the duplicate invocation check present
2. Explicitly use a maven-release-plugin release that is 3.0.0 or higher. As of their 3.x releases they don't enable the implicit release profile by default so you won't get the extra maven-source-plugin invocation added and hit the bug. You can do this as follows in the <pluginManagement> section of your pom.xml as follows:

   <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-release-plugin</artifactId>
        <version>3.0.1</version>
    </plugin>

   If you need to configure the plugin in any way then extend that with whatever configuration is appropriate.