issues with workspace resolution

Although the original issue was closed by the submitter as just needing to add <packaging>pom</packaging>, this does not resolve the issue.

It appears from my testing that workspace resolution is not handling parent poms that are not maven modules. If the attached zip from the original issue is imported into a workspace and the packaging pom is added to the parent, the error will still occur. However, if the parent pom is installed then the error no longer occurs. This error does not seem to be an issue with nested projects (maven modules), only projects using parents which are not nested.

Anders, from the description and your comment it is unclear what are you doing in order to get that error. Can you please provide step by step instructions how to reproduce. Thanks.

Sorry I wasn't clear. I may have been better off creating a new bug, but the error and previously attached example was so close I cloned it instead. Here is what I hope is a better description.

I just attached 3 example projects: parent, child, and module. From a maven perspective "parent" is the parent pom for both "child" and "module". However, on the directory structure: "parent" and "child" are siblings and "module" is nested under "parent".

The following are the steps taken to receive the error:

1) Import the 3 projects into your workspace.
2) Ensure none of them have been installed in your local repository.
3) Right click the "child" project and select: m2 Maven -> Update Project Configuration

The following error is received:

12/31/08 2:30:39 PM CST: Generating sources /child/pom.xml
12/31/08 2:30:39 PM CST: Build error for /child/pom.xml; 
org.apache.maven.reactor.MavenExecutionException: 
Error scanning for extensions: Error building model lineage in order to pre-scan for extensions: 
Cannot find artifact for parent POM: 
parent:parent::0.0.1-SNAPSHOT for project child:child:jar:0.0.1-SNAPSHOT 
at C:\temp\testworkspace\child\pom.xml
12/31/08 2:30:39 PM CST: Adding source folder /child/src/main/java
12/31/08 2:30:39 PM CST: Adding resource folder /child/src/main/resources
12/31/08 2:30:39 PM CST: Adding source folder /child/src/test/java
12/31/08 2:30:39 PM CST: Adding resource folder /child/src/test/resources
12/31/08 2:30:39 PM CST: Unable to read project /child/pom.xml; 
  org.apache.maven.extension.ExtensionScanningException: 
  Error building model lineage in order to pre-scan for extensions: 
  Cannot find artifact for parent POM: parent:parent::0.0.1-SNAPSHOT 
  for project child:child:jar:0.0.1-SNAPSHOT at C:\temp\testworkspace\child\pom.xml
12/31/08 2:30:39 PM CST: Unable to update source folders child; 
  Java Model Exception: Java Model Status 
  [Cannot nest output folder 'child/target/classes' inside output folder 'child']

When I try to update the project configuration on the "module" project, it works fine.

The above errors can be resolved by running mvn install on the "parent" project to install it into the local repository.

Based on my observations my theory is: unless the child project is a nested project to the parent, m2eclipse workspace resolution is not working as I would expect.

Hope this helps clarify.

The issue with update project configuration is a duplicate of MNGECLIPSE-645 and it does not matter if project is module or not, because right now update configuration is not using workspace resolution. See comments and vote on MNGECLIPSE-645

Anders, I've added test to cover this particular scenario and committed fix for it to trunk. Further fixes and improvements will be tracked on MNGECLIPSE-645