org.apache.jackrabbit.test.api.query.SaveTest.testRepositoryException() passes a syntactically invalid path to Query.storeAsNode() and expects a RepositoryException.
I think we should change this and pass a syntactically correct path that has an index on its last element. I believe this matches the initial intention of this test much better.
The current test prevents other JCR implementations from throwing an IllegalArgumentException for syntactically invalid paths. See also https://issues.apache.org/jira/browse/OAK-563?focusedCommentId=13556369&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13556369.