tests: add more integration tests for core tools.

tests/bats/systemd-sysusers.bats

@@ -0,0 +1,28 @@
+#!/usr/bin/env bats
+# apparmor.d - Full set of apparmor profiles
+# Copyright (C) 2024 Alexandre Pujol <alexandre@pujol.io>
+# SPDX-License-Identifier: GPL-2.0-only
+
+load common
+
+setup_file() {
+    aa_setup
+}
+
+# bats test_tags=systemd-sysusers
+@test "systemd-sysusers: Print the contents of all configuration files (before each file, its name is printed as a comment)" {
+    systemd-sysusers --cat-config
+    aa_check
+}
+
+# bats test_tags=systemd-sysusers
+@test "systemd-sysusers: Process configuration files and print what would be done without actually doing anything" {
+    systemd-sysusers --dry-run
+    aa_check
+}
+
+# bats test_tags=systemd-sysusers
+@test "systemd-sysusers: Create users and groups from all configuration file" {
+    sudo systemd-sysusers
+    aa_check
+}