system tests: cleaner, safer use of systemd

First and foremost: use ephemeral (/run, $XDG) directories
for systemd unit files, so as not to vandalize a working system.

Second, refactor common systemd-related functionality into
a new helper file, loaded by the systemd-related tests.
Shared functionality includes:

  * setting $XDG_RUNTIME_DIR if unset and rootless
  * setting $UNIT_DIR for use by tests
  * new systemctl() and journalctl() functions, which
    include "--user" when rootless (why can't systemd
    figure this out on its own?)

Signed-off-by: Ed Santiago <santiago@redhat.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/test/system/helpers.systemd.bash b/test/system/helpers.systemd.bash
new file mode 100644
index 000000000..4bde912a4
--- /dev/null
+++ b/test/system/helpers.systemd.bash
@@ -0,0 +1,30 @@
+# -*- bash -*-
+#
+# BATS helpers for systemd-related functionality
+#
+
+# podman initializes this if unset, but systemctl doesn't
+if [ -z "$XDG_RUNTIME_DIR" ]; then
+    if is_rootless; then
+        export XDG_RUNTIME_DIR=/run/user/$(id -u)
+    fi
+fi
+
+# For tests which write systemd unit files
+UNIT_DIR="/run/systemd/system"
+_DASHUSER=
+if is_rootless; then
+    UNIT_DIR="${XDG_RUNTIME_DIR}/systemd/user"
+    # Why isn't systemd smart enough to figure this out on its own?
+    _DASHUSER="--user"
+fi
+
+mkdir -p $UNIT_DIR
+
+systemctl() {
+    command systemctl $_DASHUSER "$@"
+}
+
+journalctl() {
+    command journalctl $_DASHUSER "$@"
+}