test: add tests for NOTIFYACCESS override through sd_notify

test/units/testsuite-80.service

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+[Unit]
+Description=TEST-80-NOTIFYACCESS
+
+[Service]
+ExecStartPre=rm -f /failed /testok
+ExecStart=/usr/lib/systemd/tests/testdata/units/%N.sh
+Type=oneshot

test/units/testsuite-80.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# shellcheck disable=SC2016
+set -eux
+set -o pipefail
+
+# shellcheck source=test/units/assert.sh
+. "$(dirname "$0")"/assert.sh
+
+: >/failed
+
+systemctl --no-block start notify.service
+sleep 2
+
+assert_eq "$(systemctl show notify.service -p StatusText --value)" "Test starts, waiting for 5 seconds"
+assert_eq "$(systemctl show notify.service -p NotifyAccess --value)" "all"
+sleep 5
+
+assert_eq "$(systemctl show notify.service -p NotifyAccess --value)" "main"
+assert_eq "$(systemctl show notify.service -p StatusText --value)" "Sending READY=1 in an unpriviledged process"
+assert_rc 3 systemctl --quiet is-active notify.service
+sleep 10
+
+systemctl --quiet is-active notify.service
+assert_eq "$(systemctl show notify.service -p StatusText --value)" "OK"
+assert_eq "$(systemctl show notify.service -p NotifyAccess --value)" "none"
+
+systemctl stop notify.service
+assert_eq "$(systemctl show notify.service -p NotifyAccess --value)" "all"
+
+touch /testok
+rm /failed