Posted by wolandscat on
URL: https://discuss.asciidoctor.org/Gem-paths-craziness-on-cygwin-tp3425.html

I'm not sure if the problems I have with getting gem paths to work properly are just generic ruby/gem problems but since a lot of gem installs are needed in asciidoctor, I thought I would ask here (after spending many hours scouring StackOverflow and similar places for help)...

I had a lot of trouble getting asciidoctor-pdf to run, because it installed in /usr/local/gems, but when I try to run it, it couldn't be found. gem env showed that /usr/local was indeed in the Gem path, but if I did

$ruby -r rubygems -e "p Gem.path"

it wasn't. I fixed this by doing 'export GEM_PATH=/usr/local:$GEM_PATH'. However, I would prefer to know how gem figures out its paths, and why ruby has different paths.

After this, I tried to get the compass stylesheet stuff going. Similar problem, except compass, sass etc all installed in my ~/.gem area (why?!?!) and then could not be found when invoking it. I moved it manually to /usr/local/gems, and copied the /bin scripts to /usr/local/bin, but still no luck. Using bundler appears to have messed with the paths.

If I get a new bash shell, and do 'gem env', I get 4 paths:

     - /usr/local
     - /home/Thomas/.gem/ruby
     - /usr/share/gems
     - /usr/local/share/gems

If I then do 'compass compile' I get this:

/usr/share/rubygems/rubygems/core_ext/kernel_require.rb:54:in `require': cannot                                                                     load such file -- compass (LoadError)
        from /usr/share/rubygems/rubygems/core_ext/kernel_require.rb:54:in `require'
        from /usr/local/bin/compass:20:in `block in <main>'
        from /usr/local/bin/compass:8:in `fallback_load_path'
        from /usr/local/bin/compass:19:in `<main>'

Compare this to ruby's idea of the paths:

$ ruby -r rubygems -e "p Gem.path"
["/home/Thomas/.gem/ruby", "/usr/share/gems", "/usr/local/share/gems"]

... no /usr/local!

But if I do 'export GEM_PATH=/usr/local:$GEM_PATH', I end up with only /usr/local as the GEM path according to gem env....

As you might guess, this situation is pretty irritating for someone who is a non-ruby/gem user! I have been unable to locate anywhere online clear information about how these paths are set, and why 'gem' and 'ruby' have different ideas of these paths. I have seen a lot of other posts relating to similar problems however.

Is the ruby/gems world really so arcane?

any help appreciated...