diff --git a/tool/lib/test/unit.rb b/tool/lib/test/unit.rb
index ea31804fb0..c17f19834e 100644
--- a/tool/lib/test/unit.rb
+++ b/tool/lib/test/unit.rb
@@ -324,7 +324,7 @@ module Test
         return unless @options[:parallel]
         return if @interrupt
         flush_job_tokens
-        warn e if e
+        warn e.full_message if e
         real_file = worker.real_file and warn "running file: #{real_file}"
         @need_quit = true
         warn ""