Test case testAuthorWithDiacritics fails on Mac

[stevensdavid]

Version: JabRef development head (JabRef/jabref:master at 74667e9) on Mac OS X 10.15.3 and Mac OS 10.14.5 on

The unit test case testAuthorWithDiacritics fails when executed on Mac devices, while it passes on tested Linux and Windows devices. This has been tested with AdoptOpenJDK 13.0.2.j9 and Oracle's SE JDK 13.0.2.

Steps to reproduce the behavior:

1. Build and run tests on MacOS using ./gradlew test

Gradle log:

Test testAuthorWithDiacritics() FAILED
  org.opentest4j.AssertionFailedError: expected: java.util.Collections$SingletonList@f4ce1d7<[src/test/resources/org/jabref/logic/importer/unlinkedFilesTestFolder/directory/subdirectory/2017_Gražulis_726.pdf]> but was: java.util.ArrayList@ebad2510<[src/test/resources/org/jabref/logic/importer/unlinkedFilesTestFolder/directory/subdirectory/2017_Gražulis_726.pdf]>
      at org.jabref/org.jabref.logic.util.io.RegExpBasedFileFinderTests.testAuthorWithDiacritics(RegExpBasedFileFinderTests.java:101)

[Siedlerchr]

Hm. Windows running form Eclipse can't reproduce this and CI server runs on linux.
And it's odd that it only complains the types are not equal, e.g. ArrayList vs CollectionsList. The path is otherwise equal, e.g. the diacritics, so the core functionality is working.
Therefore I will close this issue, so we can focus on other important things.