Yes, according to the RFC it shouldn't begin with a hyphen. And, since
we're on the topic, underscores were supposed to be off the table, too,
but Microsoft used them anyway, and you know what? We're gonna use the
"forbidden hyphen". And we're gonna instruct `dig` to not be so
persnickety.
fixes:
```
dig +short AAAA api.--.sslip.io
dig: idn2_lookup_ul failed: string start/ends with forbidden hyphen
```
I had to make it work for old-style (e.g. macOS dig) which is version
"DiG 9.8.3-P1" as well as for the new version ("DiG
9.11.3-RedHat-9.11.3-6.fc28") which has this new
[library](https://www.gnu.org/software/libidn/libidn2/reference/libidn2-idn2.html)
which does the following:
> Perform IDNA2008 lookup string conversion on domain name src , as described in section 5 of RFC 5891
- previously Name Server line began with "NS"
- now they begin with "Name Server"
- fixed typo
fixes:
```
1) sslip.io should have at least 2 nameservers
Failure/Error: expect(whois_nameservers.size).to be > 1
expected: > 1
got: 0
# ./sslip.io/spec/check-dns_spec.rb:37:in `block (2 levels) in <top (required)>'
```
Admittedly it's overkill to use RSpec to run a set of assertions against
a DNS server -- a simple shell script would have been shorter and more
understandable. We are using RSpec merely to practice using RSpec.
Also, RSpec is not quite appropriate because we're not testing a Ruby
class. In fact, we're not test Ruby code at all. So we should not be
using RSpec. Just sayin'.
