[MNG-8331] Sometimes versioned dependencies disappear

[jjkester]

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[mthmulders]

Corresponding IT: apache/maven-integration-testing#393.

[cstamas]

There is a more trivial PR #1822 which avoids model modification if unneeded.

[cstamas]

Another alternative mixing the two solutions: #1823

[cstamas]

@jjkester could you please add the "empty check" to the beginning of the method (so avoid any work and allocation if there is nothing to be done)? like in #1823

[jjkester]

@cstamas, I did not add one because in practice I do not expect many projects to have zero dependencies. If a project does have zero dependencies, the only "waste" is the allocation of an unnecessary ArrayList of size 0, and unnecessarily creating a new Model instance with that list. Personally I don't think that optimalization (given the assumed rarity) is worth the additional complexity in the method, which is already quite complex.

If my assumption and/or preference is not in line with the general way in which Maven is coded, I'm happy to add the optimalization, but I'd like to check the necessity first.

[cstamas]

For example, all the parents, aggregators, BOMs etc will not have any of those. This is about all the "subprojects" within a project (just to clarify "I do not expect project with zero dependencies" -- they may still have subprojects with zero deps even if project as a whole does have deps) and while I cannot tell the usual ratio of things like parent vs non-parent POMs in a project, they are there.

Just my 5cts

[cstamas]

Ugh, reformatting the file will fail the build I guess

[jjkester]

Reverted the accidental reformat, force-of-habit hotkey in IntelliJ...

[mthmulders]

The changes make sense to me. I'm happy to see the added IT's have passed, proving the bug is fixed.

[gnodet]

The changes make sense to me. I'm happy to see the added IT's have passed, proving the bug is fixed.

For the IT to run, a branch in the maven-integration-testing fork with the same name than this branch and in the same org must exists.

[jjkester]

@gnodet There is a branch with an additional integration test (contributed by @mthmulders) which is being run in the pipeline for this PR. The PR for the integration test is apache/maven-integration-testing#393

[mthmulders]

For the IT to run, a branch in the maven-integration-testing fork with the same name than this branch and in the same org must exists.

This is exactly what is happening: look for MavenITmng8331VersionedAndUnversionedDependenciesTest in this pipeline.