Test 'Jaeger::Encoders::ThriftEncoder without custom tags has ip' fails if there is only IPv6 available

[dleidert]

Hi,

as part of the packaging efforts in the Debian Linux project, we build and test all packages in IPv6-only environments. In such an environment, one test will fail, and we were wondering if you would be willing to have a look at it and deal with this:

...
Failures:

  1) Jaeger::Encoders::ThriftEncoder without custom tags has ip
     Failure/Error: expect(ip_tag.vStr).to be_a(String)

     NoMethodError:
       undefined method `vStr' for nil:NilClass
     # ./spec/jaeger/encoders/thrift_encoder_spec.rb:40:in `block (3 levels) in <top (required)>'

Finished in 0.30993 seconds (files took 0.58969 seconds to load)
187 examples, 1 failure
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https://bugs.debian.org/1000649