use find instead of mc for pruning local backups

test/compose/run.sh

@@ -29,4 +29,27 @@ fi
 
 echo "[TEST:PASS] All containers running post backup."
 
+docker-compose down
+
+# The second part of this test checks if backups get deleted when the retention
+# is set to 0 days (which it should not as it would mean all backups get deleted)
+# TODO: find out if we can test actual deletion without having to wait for a day
+BACKUP_RETENTION_DAYS="0" docker-compose up -d
+sleep 5
+
+docker-compose exec backup backup
+
+docker run --rm -it \
+  -v compose_backup_data:/data alpine \
+  ash -c '[ $(find /data/backup/ -type f | wc -l) = "1" ]'
+
+echo "[TEST:PASS] Remote backups have not been deleted."
+
+if [ "$(find ./local -type f | wc -l)" != "1" ]; then
+  echo "[TEST:FAIL] Backups should not have been deleted, instead seen:"
+  find ./local -type f
+fi
+
+echo "[TEST:PASS] Local backups have not been deleted."
+
 docker-compose down --volumes