[MNG-8520] Add cache for model resolution during project building

[gnodet]

No description provided.

[cstamas]

Tested locally, commented on https://issues.apache.org/jira/browse/MNG-8520 (tl;dr: it restores previous behaviour, excess of events are gone)

[cstamas]

@alextu Can you confirm?

[alextu]

@alextu Can you confirm?

It looks like it's better, using the reproducer I sent. I'll be able to confirm once it's merged as our test suite runs with our own nightly built from Maven master.

[cstamas]

And from where you get the nightly build? You are building it yourselves?

[alextu]

And from where you get the nightly build? You are building it yourselves?

yes on our internal CI. If really needed, I can check tomorrow how to tweak that to build a custom branch instead of master and use that in our tests.

[alextu]

I've built this branch:

mvn --version
Apache Maven 4.0.0-rc-3-SNAPSHOT (129afd91931d6cb8688ab6f03d82c43e6ceb0815)

and run our tests, they're still failing for the same reason(s) 🤔: additional requests that are not traced back to plugins.

[cstamas]

"additional requests that are not traced back to plugins" -- isnt this the https://issues.apache.org/jira/browse/MNG-8519 ? Or "additional" as "count of them is still more than was in mvn3"?

[alextu]

"additional requests that are not traced back to plugins" -- isnt this the https://issues.apache.org/jira/browse/MNG-8519 ? Or "additional" as "count of them is still more than was in mvn3"?

The count of them is more, for example, in this test, we see 153 requests with this Maven 4 version and 117 with Maven 3.9.9. We count a request when we receive a pair of RepositoryEvent objects with type ARTIFACT_DOWNLOADING (or METADATA_DOWNLOADING) and ARTIFACT_DOWNLOADED (or METADATA_DOWNLOADED).
As part of this test, we also see that some (all?) of those additional requests cannot be traced back to a plugin or a project.