Setup Login as admin Create 3 users: teacher, student1 & student2 Create a new course Group mode: Visible groups Enrol the teacher account as a teacher Enrol both student accounts as students Create two groups/memberships as follows Group A (add student1 & student2) Group B (add student2) Log out Export participants as teacher Login as teacher Navigate to course View course participants Select all users Choose With selected users... > Download table date as > Microsoft Excel (.xlsx) Confirm Groups column is present in the exported file, with content like: Student One Group A Teacher One   Student Two Group A, Group B Log out Export participants as teacher where "groups" is a hidden field that teacher can see Login as admin Navigate to Users > Permissions > User policies in site administration Select "Groups" under Hide user fields and press Save changes Log out Repeat all steps from Export participants as teacher section above Export participants as teacher where "groups" is a hidden field that teacher cannot see Login as admin Navigate to test course participants From Actions menu click on Permissions Remove the Teacher role from Roles with permission for the "moodle/course:viewhiddenuserfields" capability Log out Repeat all steps from Export participants as teacher section above, except Confirm that the Groups column is not present in the exported file Automated tests for grouplib API Run the following on each supported DB (MySQL, Oracle, Postgres, SQLServer), confirm passes $ vendor/bin/phpunit --testsuite core_testsuite --filter test_groups_get_names_concat_sql