[Reproducible-builds] Bug#794161: FTBFS: undefined method `share_as' for RSpec::ExampleGroups::FencedCodeBlock::Basic:Class (NoMethodError)

[Chris West (Faux)]

Source: ruby-bluefeather
Version: 0.41-3
Severity: serious
Tags: sid stretch
Justification: fails to build from source
User: reproducible-builds at lists.alioth.debian.org
Usertags: ftbfs

Dear Maintainer,

The package fails to build:

/usr/bin/ruby2.1 -Ku /usr/bin/rspec --pattern spec/\*.rb
/usr/lib/ruby/vendor_ruby/rspec/core/example_group.rb:656:in `method_missing': undefined method `share_as' for RSpec::ExampleGroups::FencedCodeBlock::Basic:Class (NoMethodError)
	from /tmp/buildd/ruby-bluefeather-0.41/spec/code-block.rb:33:in `block (2 levels) in <top (required)>'
	from /usr/lib/ruby/vendor_ruby/rspec/core/example_group.rb:363:in `module_exec'
	from /usr/lib/ruby/vendor_ruby/rspec/core/example_group.rb:363:in `subclass'
	from /usr/lib/ruby/vendor_ruby/rspec/core/example_group.rb:254:in `block in define_example_group_method'
	from /tmp/buildd/ruby-bluefeather-0.41/spec/code-block.rb:32:in `block in <top (required)>'
	from /usr/lib/ruby/vendor_ruby/rspec/core/example_group.rb:363:in `module_exec'
	from /usr/lib/ruby/vendor_ruby/rspec/core/example_group.rb:363:in `subclass'
	from /usr/lib/ruby/vendor_ruby/rspec/core/example_group.rb:254:in `block in define_example_group_method'
	from /usr/lib/ruby/vendor_ruby/rspec/core/dsl.rb:43:in `block in expose_example_group_alias'
	from /usr/lib/ruby/vendor_ruby/rspec/core/dsl.rb:82:in `block (2 levels) in expose_example_group_alias_globally'
	from /tmp/buildd/ruby-bluefeather-0.41/spec/code-block.rb:24:in `<top (required)>'
	from /usr/lib/ruby/vendor_ruby/rspec/core/configuration.rb:1327:in `load'
	from /usr/lib/ruby/vendor_ruby/rspec/core/configuration.rb:1327:in `block in load_spec_files'
	from /usr/lib/ruby/vendor_ruby/rspec/core/configuration.rb:1325:in `each'
	from /usr/lib/ruby/vendor_ruby/rspec/core/configuration.rb:1325:in `load_spec_files'
	from /usr/lib/ruby/vendor_ruby/rspec/core/runner.rb:103:in `setup'
	from /usr/lib/ruby/vendor_ruby/rspec/core/runner.rb:89:in `run'
	from /usr/lib/ruby/vendor_ruby/rspec/core/runner.rb:74:in `run'
	from /usr/lib/ruby/vendor_ruby/rspec/core/runner.rb:42:in `invoke'
	from /usr/bin/rspec:4:in `<main>'
/usr/bin/ruby2.1 -Ku /usr/bin/rspec --pattern spec/\*.rb failed
ERROR: Test "ruby2.1" failed. Exiting.

Full build log:
https://reproducible.debian.net/rb-pkg/unstable/amd64/ruby-bluefeather.html

-- System Information:
Debian Release: stretch/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.19.0-23-generic (SMP w/8 CPU cores)
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)