[DRE-maint] Bug#795049: ruby-rubyvis: FTBFS: cannot load such file -- rspec/expectations/differ

[Chris West (Faux)]

Source: ruby-rubyvis
Version: 0.6.1+dfsg1-1
Severity: serious
Justification: fails to build from source
Tags: sid stretch
User: reproducible-builds at lists.alioth.debian.org
Usertags: ftbfs
X-Debbugs-CC: reproducible-builds at lists.alioth.debian.org

Dear Maintainer,

The package fails to build:

┌──────────────────────────────────────────────────────────────────────────────┐
│ Run tests for ruby2.1 from debian/ruby-tests.rake                            │
└──────────────────────────────────────────────────────────────────────────────┘

RUBYLIB=/ruby-rubyvis-0.6.1+dfsg1/debian/ruby-rubyvis/usr/lib/ruby/vendor_ruby:. rake2.1 -f debian/ruby-tests.rake
/usr/bin/ruby2.1 /usr/bin/rspec --pattern ./spec/\*_spec.rb
/usr/lib/ruby/2.1.0/rubygems/core_ext/kernel_require.rb:55:in `require': cannot load such file -- rspec/expectations/differ (LoadError)
	from /usr/lib/ruby/2.1.0/rubygems/core_ext/kernel_require.rb:55:in `require'
	from /ruby-rubyvis-0.6.1+dfsg1/spec/area_spec.rb:1: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 /usr/bin/rspec --pattern ./spec/\*_spec.rb failed

Full build log:
https://reproducible.debian.net/rb-pkg/unstable/amd64/ruby-rubyvis.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_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)