test: add coverage for #27953

test/testsuite-07.units/issue27953.service

@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+[Unit]
+Description=This unit should not remain active once the shell process exits
+
+[Service]
+Type=oneshot
+ExecStart=sh -c 'sleep infinity & exit 0'

test/units/testsuite-07.issue-27953.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: LGPL-2.1-or-later
+set -eux
+set -o pipefail
+
+# Check if the unit doesn't remain in active state after the main PID exits
+# Issue: https://github.com/systemd/systemd/issues/27953
+
+systemctl start issue27953.service
+timeout 10 sh -c 'while systemctl is-active issue27953.service; do sleep .5; done'
+[[ "$(systemctl show -P ExitType issue27953.service)" == main ]]