[MNG-4427] Bad error message with duplicate dependencies that don't declare a version

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.0-alpha-3
• Fix Version/s: 3.0-alpha-3
• Component/s: Dependencies, Errors
• Assignee: Benjamin Bentmann
• Reporter: Daniel Fabulich
• Created: 04/Nov/09 18:34
• Updated: 05/Nov/09 06:41
• Resolved: 05/Nov/09 06:41

Description

Consider the attached project, which builds in Maven 2.1. The "parent" project has a dependencyManagement section that declares the version of JUnit as 3.8.1. The "child" project has duplicate dependency entries for junit; neither one declares a version.

Maven 3 generates a very misleading error message; it took a long time for me to figure out the real cause of the problem.

c:\Temp\scratch\parent>mvn clean
[INFO] Scanning for projects...
[ERROR] The build could not read 1 project -> [Help 1]
[ERROR]   The project bug:child:1.0-SNAPSHOT (C:\Temp\scratch\parent\child\pom.xml) has 2 errors
[ERROR]     'dependencies.dependency.(groupId:artifactId:type:classifier)' must be unique: junit:junit:jar -> null vs null
[ERROR]     'dependencies.dependency.version' is missing for junit:junit:jar
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/ProjectBuildingException

I expected an error more like:

'dependencies.dependency.(groupId:artifactId:type:classifier)' must be unique: junit:junit:jar -> duplicate declaration of 3.8.1

That would have been MUCH more helpful.