[Refactoring] Code clarifications, Unit Tests, Responsibilities

[afillatre]

In order to go further with the project I had the need to better understand the process behind dependency exploration and consolidation. I rewrote a great part of the depclean-core for it to be easier to understand, more testable, and with better responsibility segregation (or so I hope).

Also I added some logs that also make it clearer what happens in the process.

The DeclaredDependencyGraph calculate the dependencies and their related classes. The ActualUsedClasses collects the classes that actual are used in the project, and that match detected classes from the dependencies. Then, the ProjectDependencyAnalysisBuilder prepares the analysis result to be passed to the Maven Plugin.

I think much work is still needed since some code is still out of place in the Mojo rather than in the core (for responsibility and testability), but I hope this is a good first step.

[codecov]

Codecov Report

Merging #109 (ab671a3) into master (662d116) will increase coverage by 16.79%.
The diff coverage is 33.81%.

@@              Coverage Diff              @@
##             master     #109       +/-   ##
=============================================
+ Coverage     23.17%   39.96%   +16.79%     
- Complexity       86      178       +92     
=============================================
  Files            29       40       +11     
  Lines          1027     1126       +99     
  Branches        138       84       -54     
=============================================
+ Hits            238      450      +212     
+ Misses          758      635      -123     
- Partials         31       41       +10     

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[afillatre]

I'm actually working on a second version that completely removes the dependency to Maven in the core, so the core will be even more testable and integrate better with Gradle (no need to duplicate business code in the plugin projects)

[afillatre]

@cesarsotovalero I think I'm done for the most part. Please feel free to tell me if you like this refactoring or not, and the things you want me to change/improve.

For this second part, I totally removed the maven coupling from the core, and moved some logic into there. The idea behind that is that the plugin (maven or gradle) provides the right context for the core to execute, then exploit the result. Some more things may need to be moved to the core later, though.

Also, I ran the depclean on itself, replaced the poms with the deblaoted ones, and the project still works with no more unused dependencies, so I hope the refactoring didn't break anything.

I did not work on the Gradle project yet, so this may be broken at the moment.

[afillatre]

There is actually an issue with the debloated pom (rewrite is not working as expected), so I'll look into that.

[sonarqubecloud]

SonarCloud Quality Gate failed.   

1 Bug
0 Vulnerabilities
1 Security Hotspot
24 Code Smells

27.1% Coverage
0.0% Duplication

[cesarsotovalero]

Hi @afillatre,
Thanks for these refactorings!
I think that this separation of concerns between the functionalities that are part of the analysis and the entities that are part of the new model package makes it easy to understand.
I've fixed the Gradle plugin accordingly.
I'll merge this PR.
Please open another PR if you want to add a new feature to DepClean 🚀

[afillatre]

@cesarsotovalero thanks for accepting it ! I still have some improvements to add, and some proposals to make