Rails' binstubs vs. Bundler binstubs
There's an incompatibility in the Rails vs Bundler-generated
Futher, other Bundler-generated binstubs (e.g.,
bin/rspec) generated by older versions of Bundler don't play well with those generated by Bundler v1.16.
The Binstubs and versions.
The older rspec-old.rb was generated by an older version of Bundler.