jgit extension produces warnings with Maven 3.9.0

[Bananeweizen]

Maven 3.9.0 seems to validate entries in the configuration blocks against the declared parameters of a mojo. I've found some deprecated/removed config entries in other plugins that way. Unfortunately Tycho throws warnings simply because of not declared parameters in the jgit timestamp provider. The code of that plugin just XML-parses the configuration block instead of defining any parameters.

[INFO] ------------------< com.etas.common:com.etas.commons >------------------
[INFO] Building com.etas.commons 5.6.5-SNAPSHOT                          [2/51]
[INFO]   from ..\..\plugins\com.etas.commons\pom.xml
[INFO] ---------------------------[ eclipse-plugin ]---------------------------
[WARNING] Parameter 'jgit.dirtyWorkingTree' is unknown for plugin 'tycho-packaging-plugin:2.7.5:build-qualifier (default-build-qualifier)'
[WARNING] Parameter 'jgit.ignore' is unknown for plugin 'tycho-packaging-plugin:2.7.5:build-qualifier (default-build-qualifier)'
[WARNING] Parameter 'jgit.dirtyWorkingTree' is unknown for plugin 'tycho-packaging-plugin:2.7.5:validate-id (default-validate-id)'
[WARNING] Parameter 'jgit.ignore' is unknown for plugin 'tycho-packaging-plugin:2.7.5:validate-id (default-validate-id)'
[WARNING] Parameter 'jgit.dirtyWorkingTree' is unknown for plugin 'tycho-packaging-plugin:2.7.5:validate-version (default-validate-version)'
[WARNING] Parameter 'jgit.ignore' is unknown for plugin 'tycho-packaging-plugin:2.7.5:validate-version (default-validate-version)'
[WARNING] Parameter 'jgit.dirtyWorkingTree' is unknown for plugin 'tycho-packaging-plugin:2.7.5:update-consumer-pom (default-update-consumer-pom)'
[WARNING] Parameter 'jgit.ignore' is unknown for plugin 'tycho-packaging-plugin:2.7.5:update-consumer-pom (default-update-consumer-pom)'
[WARNING] Parameter 'jgit.dirtyWorkingTree' is unknown for plugin 'tycho-packaging-plugin:2.7.5:package-plugin (default-package-plugin)'
[WARNING] Parameter 'jgit.ignore' is unknown for plugin 'tycho-packaging-plugin:2.7.5:package-plugin (default-package-plugin)'

To reproduce, any configuration block like in the example here will be sufficient: https://wiki.eclipse.org/Tycho/Reproducible_Version_Qualifiers
I'm not sure where exactly the warning is raised, and whether there is something to disable this new feature.

[laeubi]

Tycho currently not support maven 3.9x
Also as jgit is an extension, we can't effectively declare its parameters here, I have already evaluated some alternatives but have not yet had the time to work on it.

[laeubi]

See also:

• Investigate Maven 3.9.0 #2084

[Bananeweizen]

Honestly, does the jgit timestamp provider really have to be an extension of the default provider? Can't we make that 2 alternative implementations, and let people user either default or jgit? That way both could have their own configs, people would not be confused with dependencies, the POM would look much cleaner. And since 4.0 is a breaking change anyway, this would be fine to do now.
Code sharing between them would be as simple as before, given they live in the same repo.

[laeubi]

Currently it is an extension of tycho-packaging-plugin (because otherwise the tycho-packaging-plugin can't "see" other plugins due to maven design)... but I recently generalized the concept of of Plugins contributing extensions by using the org.eclipse.tycho.helper.PluginRealmHelper that tricks maven a bit in this regard... so if you like give it a try it will include the following steps:

1. Create a tycho-jgit-plugin
2. Create a JGitTimeStampProviderMojo
3. Implement a BuildTimestampProvider that reads the config from the mojo by checking the maven project (there will soon be a new helper to even simplify that)
4. Adjust places where BuildTimestampProvider is used to use the PluginRealmHelper
5. Add a release note and adjust integrationtests and examples, possibly clean up things (e.g. MojoExecution might not be required anymore as the config do not longer come from the tycho-packaging-plugin)

If you need any further help let me know.