[MCHECKSTYLE-412] - Exclude generated sources / test-sources from defau…

[gmshake]

…lt source / test-source directories

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[slawekjaranowski]

Does the effect not will be the same as we will use for default:

project.build.sourceDirectory
project.build.testSourceDirectory

without special filtering ...

[gmshake]

Does the effect not will be the same as we will use for default:

project.build.sourceDirectory
project.build.testSourceDirectory

without special filtering ...

Not exactly.

In my team we have many projects specify the sourceDirectories as we have JPA annotation processors and OpenAPI tools to generate REST API stubs. It is a burden we specify it now and then, so it will be perfectly that the default setting works OOB.
I had tried to change sourceDirectories default to project.build.sourceDirectory but it breaks https://issues.apache.org/jira/browse/MCHECKSTYLE-70 as some users use build-helper-maven-plugin to inject source directories to the build. It looks that the best solution is excluding generated sources / test-sources from the build (project.compileSourceRoots / project.testCompileSourceRoots) before sending them to checkstyle.

It will be perfect that Maven core provide some API like getGeneratedCompileSourceRoots / getGeneratedTestCompileSourceRoots but apparently it will not go for 3.6.x and earlier versions (3.0.x, 3.3.x) . Since the generated sources / test-sources should be in build target directory we can bravely exclude the entire build target directory.

[michael-o]

What if I want to invert this and do check generated source?

[gmshake]

What if I want to invert this and do check generated source?

Well, this PR changes the default settings. You can still specify the sourceDirectories and testSourceDirectories, then checkstyle will check those directories.

[elharo]

Anyone want to resolve conflicts and merge? This would be useful.

[gmshake]

Anyone want to resolve conflicts and merge? This would be useful.

I'll rebase it at this weekend.

I do not have write access to the Apache repository so I'll leave the merge to someone who's capable to do.

[gmshake]

1. Rebased onto latest master
2. Added a knob excludeGeneratedSources to not break existing setups, it is false by default

[michael-o]

Would be nice if this would have an IT showning the benefit.

[gmshake]

@michael-o

Would be nice if this would have an IT showning the benefit.

Done !

[michael-o]

@michael-o

Would be nice if this would have an IT showning the benefit.

Done !

Testing...

[gmshake]

Thanks!