err.Name = name
	}
	return dnsmessage.Parser{}, "", err
}

// avoidDNS reports whether this is a hostname for which we should not
// use DNS. Currently this includes only .onion, per RFC 7686. See
// golang.org/issue/13705. Does not cover .local names (RFC 6762),
// see golang.org/issue/16739.
func avoidDNS(name string) bool {
	if name == "" {
		return true
	}
	if name[len(name)-1] == '.' {

		// private.
		{"local", false},
		{"onion", false},
		{"local.", false},
		{"onion.", false},
	}
	for _, tt := range tests {
		got := avoidDNS(tt.name)
		if got != tt.avoid {
			t.Errorf("avoidDNS(%q) = %v; want %v", tt.name, got, tt.avoid)
		}
	}
}

func TestNameListAvoidDNS(t *testing.T) {
	c := &dnsConfig{search: []string{"go.dev.", "onion."}}
	got := c.nameList("www")