Fix test fail caused by bundler-1.13.x

[hsbt]

bundler-1.13.0 references Gem::Source. It is only provided from rubygems-2.6.x

[drbrain]

Hrm, Gem::Source should exist for all of RubyGems 2.x

[hsbt]

rubygems/bundler#4944

It is caused by implicitly loading of Gem::Source, so rubygems 2.5 and 2.4 did not load it probably.

[hsbt]

And I noticed travis boxes defects that no effects with rubygems and bundler downgrading to @BanzaiMan

[aycabta]

I researched about this.

rubygems/bundler#4944 is merged at rubygems/bundler@3b5d047, this merge commit hasn't been in 1.13. The error what says NameError: uninitialized constant Gem::Source will fixed by this commit with new release.

But, there is another problem in Bundler's HEAD. Gem::Specification#full_gem_path in bundler/rubygems_ext.rb uses Bundler::Plugin::API::Source. The namespace is defined by cascading autoload:

• Bundler::Plugin uses autoload for bundler/plugin/api
• Bundler::Plugin::API uses autoload for bundler/plugin/api/source
• Gem::Specification#full_gem_path in bundler/rubygems_ext.rb is re-called through require of rubygems/core_ext/kernel_require.rb because bundler/plugin/api/source uses require before Bundler::Plugin::API::Source is defined
• Above cycle repeats, but second autoloading bundler/plugin/api/source is skipped

Finally, NameError: uninitialized constant Bundler::Plugin::API::Source is occurred. The require in Bundler::Plugin::API::Source is added at rubygems/bundler@b94002b, this commit haven't been released. So we haven't known this error.

I don't have a detailed knowledge about Rake and Bundler, tentatively I just report.

[aycabta]

Gem::Source error fixes Bundler 1.13.1. Bundler::Plugin::API::Source error fixes rubygems/bundler#4973 ...when merged.

[hsbt]

@aycabta Thank you for your notification. I will try to bundler 1.13.1 when it released.

[hsbt]

bundler-1.13.1 is still failing... :( https://travis-ci.org/ruby/rake/jobs/159734476

[hsbt]

submitted rubygems/bundler#4981

[aycabta]

I think that is the best workaround...