https://github.com/hibernate/hibernate-test-case-templates/pull/7
Here is a test for HHH-10774 - SortedMap defined in .hbm.xml are not sortable In Progress . There is the same test in both test-case-template-hibernate-orm4 and test-case-template-hibernate-orm5 with a SortedMap. It works on hibernate4. It doesn't on hibernate5 without the PluralAttributeSourceMapImpl patch.