Scenario

1. Build a (pomless) language project (in this case nabl2) from the commandline with mvn install.
2. Maven produces the following warnings:
   [WARNING] The POM for org.metaborg:spoofax-maven-plugin-pomless:jar:2.0.0-SNAPSHOT is missing, no dependency information available
[WARNING] Failed to read extensions descriptor /Users/hendrik/slde/spoofax-releng.git/runtime-libraries/org.metaborg.meta.lib.analysis2/.mvn/extensions.xml: Plugin org.metaborg:spoofax-maven-plugin-pomless:2.0.0-SNAPSHOT or one of its dependencies could not be resolved: Could not find artifact org.metaborg:spoofax-maven-plugin-pomless:jar:2.0.0-SNAPSHOT
3. The build fails later on because language dependencies are not loaded.

Expected result

Maven downloads the pomless plugin, just as it would with a normal extensions specified in pom.xml.

Work-around

Locally mvn install the spoofax-maven-plugin-pomless project.

Submitted by Hendrik van Antwerpen on 24 February 2016 at 19:37

This is a Maven bug; profiles with repositories which are activated by default are not activated during the resolution of core extensions. However, you can activate these profiles using the following section in your settings file:

<activeProfiles>
  <activeProfile>add-metaborg-release-repos</activeProfile>
  <activeProfile>add-metaborg-snapshot-repos</activeProfile>
  <activeProfile>add-spoofax-eclipse-repos</activeProfile>
</activeProfiles>

That should enable resolution of core extensions from our repositories. I will file a Maven bug report.

Maven bug report at https://issues.apache.org/jira/browse/MNG-5984.

It is fixed in Maven 3.4, but that is not released yet.