Use String#dup in Excon::Utils#binary_encode for frozen string

[unasuke]

Hi, I'm Itamae gem maintainer.
https://github.com/itamae-kitchen/itamae

probrem

I found itamae gem's CI failing on ruby-head (it will release as Ruby 2.7).
I investigated about that reason.
CI failing by excon called from docker-api gem.
https://travis-ci.org/itamae-kitchen/itamae/builds/625473573

11: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/docker-api-1.34.2/lib/docker/connection.rb:40:in `request'
10: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/connection.rb:275:in `request'
 9: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/middlewares/base.rb:22:in `request_call'
 8: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/middlewares/base.rb:22:in `request_call'
 7: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/middlewares/base.rb:22:in `request_call'
 6: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/middlewares/idempotent.rb:19:in `request_call'
 5: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/middlewares/instrumentor.rb:34:in `request_call'
 4: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/middlewares/mock.rb:57:in `request_call'
 3: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/middlewares/redirect_follower.rb:15:in `request_call'
 2: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/connection.rb:164:in `request_call'
 1: from /home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/utils.rb:15:in `binary_encode'
/home/travis/build/itamae-kitchen/itamae/vendor/bundle/ruby/2.7.0/gems/excon-0.71.0/lib/excon/utils.rb:15:in `force_encoding': can't modify frozen String: "" (FrozenError) (Excon::Error::Socket)

solution

Therefore, use String#dup in Excon::Utils#binary_encode for frozen string literal, and caller assign returned duplicated string to a variable.

https://travis-ci.org/itamae-kitchen/itamae/builds/626589627

[geemus]

Hey, thanks for the detailed report and fix. I just have one area I'd like to discuss, which I'll comment on directly. Thanks!

[geemus]

Looks good, thanks again for the detailed report, fix, and quick update.

[geemus]

@unasuke do you need a release with these changes?

[unasuke]

@geemus Yes! I want a new release! 😆
But I'll leave it up to you if you busy. ☺️

[geemus]

No worries, if you didn't care I would probably just wait, but it's pretty easy to do.

Released in v0.71.1.

Thanks again!

[unasuke]

Thank you too!