[DRE-maint] Bug#888188: ruby-hashie: FTBFS on ruby2.5: stack overflow around Integer

[Chris West (Faux)]

Source: ruby-hashie
Version: 3.4.4-1
Severity: important
User: debian-ruby at lists.debian.org
Usertags: ruby2.5

Dear Maintainer,

This package fails to build against ruby2.5. Soon, there will
be a transition to ruby2.5, and this package will FTBFS in sid.

There may be some details on the wiki about common problems:
https://wiki.debian.org/Teams/Ruby/Ruby25Transition

Build log excerpt:

Failures:

  1) Hashie::Extensions::Coercion#coerce_value core types raises a CoercionError when coercion is not possible
     Failure/Error: if ABSTRACT_CORE_TYPES.key? from

     SystemStackError:
       stack level too deep
     # ./lib/hashie/extensions/coercion.rb:113:in `key?'
     # ./lib/hashie/extensions/coercion.rb:113:in `coerce_value'
     # ./lib/hashie/extensions/coercion.rb:115:in `block in coerce_value'
     # ./lib/hashie/extensions/coercion.rb:114:in `each'
     # ./lib/hashie/extensions/coercion.rb:114:in `coerce_value'
     # ./lib/hashie/extensions/coercion.rb:115:in `block in coerce_value'
     # ./lib/hashie/extensions/coercion.rb:114:in `each'

[... .. yes, lots of ...]

     # ./lib/hashie/extensions/coercion.rb:115:in `block in coerce_value'
     # ./lib/hashie/extensions/coercion.rb:114:in `each'
     # ./lib/hashie/extensions/coercion.rb:114:in `coerce_value'
     # ./lib/hashie/extensions/coercion.rb:115:in `block in coerce_value'
     # ./lib/hashie/extensions/coercion.rb:114:in `each'
     # ./lib/hashie/extensions/coercion.rb:114:in `coerce_value'
     # ./spec/hashie/extensions/coercion_spec.rb:587:in `block (4 levels) in <top (required)>'

Finished in 0.30331 seconds (files took 0.38196 seconds to load)
616 examples, 3 failures

Failed examples:

rspec ./spec/hashie/extensions/coercion_spec.rb:560 # Hashie::Extensions::Coercion#coerce_value core types raises a CoercionError when coercion is not possible
rspec ./spec/hashie/extensions/coercion_spec.rb:565 # Hashie::Extensions::Coercion#coerce_value core types coerces Integer to String
rspec ./spec/hashie/extensions/coercion_spec.rb:586 # Hashie::Extensions::Coercion#coerce_value core types coerces Numeric to String

/usr/bin/ruby2.5 /usr/bin/rspec --pattern ./spec/\*\*/\*_spec.rb --format documentation failed
ERROR: Test "ruby2.5" failed. Exiting.
dh_auto_install: dh_ruby --install /build/ruby-hashie-3.4.4/debian/ruby-hashie returned exit code 1
debian/rules:6: recipe for target 'binary' failed
make: *** [binary] Error 1
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2

Full build log:
https://rbuild.fau.xxx/2018-01-23/ruby-hashie.log

Please fix it!

Cheers,
Chris.