+test_begin_subtest "Xapian exception: read only files"
+chmod u-w ${MAIL_DIR}/.notmuch/xapian/*.DB
+output=$(notmuch tag +something '*' 2>&1 | sed 's/: .*$//' )
+chmod u+w ${MAIL_DIR}/.notmuch/xapian/*.DB
+test_expect_equal "$output" "A Xapian exception occurred opening database"
+