Add spec for when inquiring about nonexistent gem
Add spec for when inquiring about nonexistent gem

If the gem we are looking for does not exist, RubyGems API returns
a string "This rubygem could not be found." which is problematic
for the JSON parser.
This issue has been reported to rubygems.org.
https://github.com/rubygems/rubygems.org/issues/1683

rubygems/gems