Maven -> Update Projects vs checked in files

[cdietrich]

Maven -> Update Projects changes checked in files .classpath, .project. these might also leave projects uncompilable e.g. generatorxxx folders in xtend.core vanish

we should check what we can do about this

[LorenzoBettini]

Yes, I know. In fact, in oomph setup I disabled the corresponding options. As far as I know, there are a few open bugs in m2e. For the moment, there's not much we can do about that.

Concerning the generator folders in xtend core maybe we can configure build helper maven plugin appropriately to add those folders as source folders..

[HannesWell]

On my Windows computer I also notice that some extend files are generated with different line separators in strings compared to how they are committed. This leads to about 8 changed files in my Git-Staging when I run a full workspace build.
I wonder if those xtend-generated files can be ignored by git, if they are generated anyways.

Yes, I know. In fact, in oomph setup I disabled the corresponding options. As far as I know, there are a few open bugs in m2e. For the moment, there's not much we can do about that.

Can you point me to the exact bugs?

[cdietrich]

Regarding Xtend

#2293
xtext/xtext-monorepo#12

[LorenzoBettini]

Can you point me to the exact bugs?

IIRC,
eclipse-m2e/m2e-core#1200
eclipse-m2e/m2e-core#1239
eclipse-m2e/m2e-core#1278

[LorenzoBettini]

Concerning generatorxxx folders in xtend.core, I guess that is due to the build.properties:

src.excludes = generator/,\
               generator-xtend-gen/

and I guess we want it that way?

[cdietrich]

we want to have this a source folders but not package. also building with maven is not a must

[LorenzoBettini]

I don't understand the last part.

[cdietrich]

we dont run the workflow from maven. so there is no strict need to compile with maven. i also dont know if it would cause of the jflex thing.
also strictly the generator stuff and the rest would need to be compiled in 2 steps

[LorenzoBettini]

but I don't understand what you propose...

[cdietrich]

i propose nothing. i dont know a solution yet.

[szarnekow]

Is it possible in maven to have something next to src/main and src/test? What we effectively need is src/generator, so a source folder that is neither test nor production.

[mickaelistria]

The issue comes from m2e, as linked by @LorenzoBettini earlier. PRs to fix that in m2e would be highly welcome!

[mickaelistria]

FWIW, I investigated it in m2e and the .project changes proposed by m2e do happen from time to time, but are stable: as long as the Maven Nature is present and Maven Builder is the last one defined in the .project, m2e shouldn't modify the .project. So maybe you can just commit those .project is m2e has "fixed" them (it can happen eg if you enable another builder, it usually becomes the last on the list and then m2e will want to modify your .project as long as it's not the last one running).
For the .classpath, I would recommend that one usually does not check them into SCM unless they have specific manually maintained configuration in those. If the pom.xml are configured in a standard enough way, the .classpath will always be correct and regenerated on project update. So it's often better to just not check it in and .gitignore it.