Clover Maven Plugin adds "clover" classifier for directory-based artifacts

Problem

Clover Maven Plugin replaces list of artifacts and artifacts dependencies by using an artifact with the "clover" classifier if any such exists.

This is useful for "clover:instrument" goal and multi-module Maven builds, because this way instrumented module can use instrumented dependencies (instead of normal ones).

However, a build can have an artifact being a '/target/classes' folder (for a current module compiled). Maven's artifact resolver resolves such directory to be an artifact with a "clover" classifier too. Example:

As Clover "sees" such artifact as resolved, it replaces it by the "clover" one, despite the fact that this is the same location.

This is superfluous.

In a normal build it works fine, but it fails when aspectj-maven-plugin is used together with clover-maven-plugin. See:

• https://answers.atlassian.com/questions/39984820
• CLV-6357 ticket

Possible fixes

• do not add "clover" classifier to artifacts in the same location
• do not swizzle artifacts in clover:setup
• do not swizzle artifacts if useCloverClassifier=false (extend usage of this property)

Workaround

Set cloveredArtifactExpiryInMillis=-1. This will trick Clover to see all 'clover' artifacts as outdated. Warning in logs is produced:

[WARNING] Using [<artifact>], built on <date> even though a Clovered version exists but it's older (lastModified: <date> ) and could fail the build. Please consider running Clover again on that dependency's project.

• note that setting useCloverClassifier=false does not help (this is for output artifacts, not dependencies)
• note that changing "clover:instrument" to "clover:setup" does not help