Weird DateFormattersTests failure in Git repository

[cbismuth]

Hi,

I encountered a weird DateFormattersTests failure while running a gradlew check.

Here is the line to reproduce below, does any one understand why this test fails?

Besides, when I run it within IntelliJ, it passes ...

Thanks,
Chris

Suite: org.elasticsearch.common.time.DateFormattersTests
  1> [2018-10-09T12:42:23,575][WARN ][o.e.b.JNANatives         ] [[SUITE-DateFormattersTests-seed#[989AA2D5B26A1236]]] Unable to lock JVM Memory: error=12, reason=Cannot allocate memory
  1> [2018-10-09T12:42:23,580][WARN ][o.e.b.JNANatives         ] [[SUITE-DateFormattersTests-seed#[989AA2D5B26A1236]]] This can result in part of the JVM being swapped out.
  1> [2018-10-09T12:42:23,581][WARN ][o.e.b.JNANatives         ] [[SUITE-DateFormattersTests-seed#[989AA2D5B26A1236]]] Increase RLIMIT_MEMLOCK, soft limit: 65536, hard limit: 65536
  1> [2018-10-09T12:42:23,582][WARN ][o.e.b.JNANatives         ] [[SUITE-DateFormattersTests-seed#[989AA2D5B26A1236]]] These can be adjusted by modifying /etc/security/limits.conf, for example: 
  1>    # allow user 'cbismuth' mlockall
  1>    cbismuth soft memlock unlimited
  1>    cbismuth hard memlock unlimited
  1> [2018-10-09T12:42:23,583][WARN ][o.e.b.JNANatives         ] [[SUITE-DateFormattersTests-seed#[989AA2D5B26A1236]]] If you are logged in interactively, you will have to re-login for the new limits to take effect.
  1> [2018-10-09T14:42:24,957][INFO ][o.e.c.t.DateFormattersTests] [testLocales] before test
  1> [2018-10-09T14:42:25,399][INFO ][o.e.c.t.DateFormattersTests] [testLocales] after test
  2> REPRODUCE WITH: ./gradlew :server:test -Dtests.seed=989AA2D5B26A1236 -Dtests.class=org.elasticsearch.common.time.DateFormattersTests -Dtests.method="testLocales" -Dtests.security.manager=true -Dtests.locale=ar-LB -Dtests.timezone=Asia/Muscat -Dtests.distribution=oss-zip -Dcompiler.java=11 -Druntime.java=8
FAILURE 0.53s | DateFormattersTests.testLocales <<< FAILURES!
   > Throwable #1: junit.framework.AssertionFailedError: Expected exception IllegalArgumentException but no exception was thrown
   >    at __randomizedtesting.SeedInfo.seed([989AA2D5B26A1236:E53315FCC176BA66]:0)
   >    at org.apache.lucene.util.LuceneTestCase.expectThrows(LuceneTestCase.java:2687)
   >    at org.apache.lucene.util.LuceneTestCase.expectThrows(LuceneTestCase.java:2672)
   >    at org.elasticsearch.common.time.DateFormattersTests.testLocales(DateFormattersTests.java:85)
   >    at java.lang.Thread.run(Thread.java:748)
  2> NOTE: leaving temporary files on disk at: /home/cbismuth/git/elasticsearch/server/build/testrun/test/J0/temp/org.elasticsearch.common.time.DateFormattersTests_989AA2D5B26A1236-001
  2> NOTE: test params are: codec=Asserting(Lucene80): {}, docValues:{}, maxPointsInLeafNode=505, maxMBSortInHeap=5.159543813935031, sim=Asserting(org.apache.lucene.search.similarities.AssertingSimilarity@14a3f7e0), locale=ar-LB, timezone=Asia/Muscat
  2> NOTE: Linux 4.15.0-36-generic amd64/Oracle Corporation 1.8.0_181 (64-bit)/cpus=4,threads=1,free=420529136,total=514850816
  2> NOTE: All tests run in this JVM: [DateFormattersTests]
Completed [1/1] in 2.76s, 1 test, 1 failure <<< FAILURES!