// Test with mock
            doNothing().when(mockReferralData).fixupHost(fqdn);
            mockReferralData.fixupHost(fqdn);
            verify(mockReferralData, times(1)).fixupHost(fqdn);

            // Test with concrete implementation - requires server to be set
            assertDoesNotThrow(() -> concreteImplementation.fixupHost(fqdn));
        }

        @Test
        @DisplayName("Should fixup domain")

            referralData.fixupHost("server.example.com");

            assertEquals("server.example.com", referralData.getServer());
        }

        @Test
        @DisplayName("Should not fixup host for non-matching FQDN")
        void testFixupHostWithNonMatchingFQDN() {
            setupReferralWithServer("SERVER");

            referralData.fixupHost("other.example.com");

    /**
     * Replaces the host with the given FQDN if it is currently unqualified
     *
     * @param fqdn the fully qualified domain name to use
     */
    void fixupHost(String fqdn);

    /**
     * Possibly appends the given domain name to the host name if it is currently unqualified
     *
     * @param domain the domain name to append
     */
    void fixupDomain(String domain);

                log.debug(String.format("Applying DFS netbios name hack %s -> %s ", s, fqdn));
            }
            this.server = fqdn;
        }
    }

    @Override
    public void fixupHost(final String fqdn) {
        final String s = getServer();
        if (s.indexOf('.') < 0 && s.toUpperCase(Locale.ROOT).equals(s)) {
            if (fqdn.startsWith(s.toLowerCase(Locale.ROOT) + ".")) {

        final DfsReferralDataInternal dri = (DfsReferralDataInternal) dr;

        if (tc.getConfig().isDfsConvertToFQDN()) {
            dri.fixupHost(server);
        }

        if (log.isDebugEnabled()) {
            log.debug("Adding key " + key + " to " + dr);
        }

        /*