test: add test case for issue #38765

src/core/transaction.c

@@ -172,6 +172,7 @@ static int delete_one_unmergeable_job(Transaction *tr, Job *job) {
                                  * another unit in which case we
                                  * rather remove the start. */
 
+                                /* Update test/units/TEST-87-AUX-UTILS-VM.sh when logs below are changed. */
                                 log_unit_debug(j->unit,
                                                "Looking at job %s/%s conflicted_by=%s",
                                                j->unit->id, job_type_to_string(j->type),

test/units/TEST-87-AUX-UTILS-VM.sh

@@ -3,6 +3,14 @@
 set -eux
 set -o pipefail
 
+# For issue #38765
+journalctl --sync
+if journalctl -q -o short-monotonic --grep "Looking at job .*/.* conflicted_by=(yes|no)" >/failed; then
+    echo "Found unexpected unmergeable jobs"
+    cat /failed
+    exit 1
+fi
+
 # shellcheck source=test/units/test-control.sh
 . "$(dirname "$0")"/test-control.sh