}
            assertEquals(expectedPathConsumed, combined.getPathConsumed());
        }

        @Test
        @DisplayName("Should combine when first has null path")
        void testCombineWithNullPath() {
            // Create first with null path
            DfsReferralDataImpl first = new DfsReferralDataImpl();
            when(mockReferral.getTtl()).thenReturn(300);