[SUREFIRE-2210] - Restore ordering of additional class path elements

[dmlloyd]

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The recent change (47eb197, since 3.2.0) to support more additional class path items during test has broken the use case of testing multi-release projects where ordering of class path elements is significant by changing the additional class path items collection from a List to a HashSet, which has unreliable ordering semantics. This simple fix preserves the original class path order specified in the POM by using a LinkedHashSet, which preserves insertion order, instead of a HashSet, which does not.

/cc @kwin

[dmlloyd]

I've added a test, however it's not clear that this will always detect a regression. The reason is that the problem was caused by the unpredictable iteration order of HashSet; it's possible that the iteration order of HashSet is coincidentally correct for a given set, thus it's difficult to detect the error with 100% certainty. Still, having the test may catch a regression someday.

[kwin]

@dmlloyd Looks good to me. Thanks. Just one minor stylistic remark.

[dmlloyd]

Pushed up a fix to a funny little class loader bug relating to canonicalization of paths when using ClassLoader#getResources with an absolute path name. I'm sure it's fine...

[dmlloyd]

Is there some procedure to request a release of Surefire with this fix? @Tibor17 are you the person to ask?

Thanks...

[dmlloyd]

/cc @slawekjaranowski, could I please request a release including this fix? Thank you!

[kwin]

The mailing list is the proper place to ask for a release.