refactor: Excluding decompiler related features from spoon-core

[nharrand]

Attempt to implement #2747
Related to #2737

[nharrand]

This is a PoC of what could be a split of spoon into different artifacts. WDYT?
I would like to reuse architectural tests (unused import, package creation, force documentation of public api...), does anyone have an opinion on how to make this tests more reusable?

[monperrus]

Looks really good to me. This will enable to have a clean Maven central release without any odd dependency.

We can also add a travis job to test it.

@surli with respect to our conversation, WDYT?

[nharrand]

I deactivated travis builds for spoon-bytecode because it relies on resolving spoon-core which in turn has spoon-pom as a parent, which is not publish yet, so it fails. We ca just uncomment the two builds in a futur PR. Otherwise, this is ready for review.

[nharrand]

Similarly properties could be move into spoon-pom, but ... #2771

[surli]

FTR I got an email from the CFR maintainer:

CFR 0.135 (damnit, I even changed my naming scheme to conform, ish. ;) ) is now available on maven central.

<dependency>
  <groupId>org.benf</groupId>
  <artifactId>cfr</artifactId>
  <version>0.135</version>
</dependency>

[nharrand]

Except for the remaining discussion on the name (and possibly, the README.md). This PR is ready for review.

[pvojtechovsky]

I do not use Maven and I don't try to understand that building stuff, but I like the idea of this PR a lot. 👍 Thank You Nicolas!

[surli]

Sorry for asking lot of changes but the idea here is really to have a first external module of Spoon to start seeing how we can decompose some parts, so the most info we can put in an external pom and reuse, the better.
By the way, a good thing you can try before we merge the PR is a dry-run mvn release, on spoon-pom: mvn release:prepare -DdryRun=true, this will check that everything's ok to release all spoon artefacts at once. Thanks

[nharrand]

Sorry for asking lot of changes but the idea here is really to have a first external module of Spoon to start seeing how we can decompose some parts, so the most info we can put in an external pom and reuse, the better.

Don't be, it's actually helpful. But, to answer a lot of your comments, my problem is that spoon-pom is not yet published on maven central. So, locally on my machine I can move a lot of things in spoon-pom, but if I do, I'll break CI. So I was trying to achieve an ugly middle ground where I add stuff to spoon-pom, planing to remove them from other poms later.
Do you have an other solution? (Should I not care to break CI, if everything run smoothly locally?)

[surli]

Do you have an other solution? (Should I not care to break CI, if everything run smoothly locally?

Change CI scripts to run directly all tests from spoon-pom.

[spoon-bot]

API changes: 7 (Detected by Revapi)

Old API: fr.inria.gforge.spoon:spoon-core:jar:7.2.0-20181120.234134-99 / New API: fr.inria.gforge.spoon:spoon-core:jar:7.2.0-SNAPSHOT

	Class was removed.
Old	class JarLauncher
New	none
Breaking	binary: breaking

	Class was removed.
Old	class CFRDecompiler
New	none
Breaking	binary: breaking

	Class was removed.
Old	interface Decompiler
New	none
Breaking	binary: breaking

	Class was removed.
Old	class FernflowerDecompiler
New	none
Breaking	binary: breaking

	Class was removed.
Old	class MultiTypeTransformer
New	none
Breaking	binary: breaking

	Class was removed.
Old	class SpoonClassFileTransformer
New	none
Breaking	binary: breaking

	Class was removed.
Old	interface TypeTransformer
New	none
Breaking	binary: breaking

[surli]

you removed checkstyle from spoon-core, so I assume you put it in spoon-pom, so it means you don't need it here.

[nharrand]

No. Both spoon-core and spoon-decompiler declare the checkstyle plugin but with differents options (exculsion of some sources for exemple).

[nharrand]

But the checkstyle profile is now in spoon-pom.

[monperrus]

We did the last changes per our discussion, CI is green.

@surli do you merge?