npm - Why are my Yeoman generators installing in the wrong place?

Question

I have a problem with Yeoman generators. They install just fine if I run "npm install [generator-name] -g". However when I try to run "yo [generator-name] yeoman can't seem to find the generator. Neither is it listed among my other generators if I just run "yo". I've tried a bunch of generators and the result is always the same.

After a bit of bit of investigation I found that the downloaded generator is placed in

/usr/local/lib/node_modules/

But my other generators are placed in

/usr/local/lib/share/npm/lib/node_modules/

Here is an image of how it looks on my machine http://i.imgur.com/DxWTYHb.png, I'm running OSX in case that matters. Looks like something is wrong to me - but I cannot figure it out.

Not sure if this helps, but brew doctor and $NODE_PATH return nothing while $PATH returns:

-bash: 
/usr/local/share/npm/bin:
/Users/marcus/.rvm/gems/ruby-2.0.0-p247/bin:
/Users/marcus/.rvm/gems/ruby-2.0.0-p247@global/bin:
/Users/marcus/.rvm/rubies/ruby-2.0.0-p247/bin:
/Users/marcus/.rvm/bin:
/usr/bin:
/bin:
/usr/sbin:
/sbin:
/usr/local/bin:
/usr/local/git/bin: No such file or directory

UPDATE

---

I tried what Eddie Monge Jr suggested and now my angular generator works fine. However when I installed another generator (chrome-extension) yeoman insists that it's not installed/found.

When I run ls $(npm config get prefix)/lib/node_modules I get this:

bower                      generator-mocha
generator-angular          grunt-cli
generator-chrome-extension npm
generator-karma            yo

And npm list -g returns this (I cut out a lot of generic stuff)

/usr/local/lib
├─┬ bower@1.2.3
├─┬ generator-angular@0.4.0
│ └─┬ yeoman-generator@0.13.3
├─┬ generator-chrome-extension@0.2.3
│ └─┬ yeoman-generator@0.12.3
├─┬ generator-karma@0.5.0
│ └─┬ yeoman-generator@0.13.3
├─┬ generator-mocha@0.1.1
│ └─┬ yeoman-generator@0.10.5
├─┬ grunt-cli@0.1.9
├─┬ npm@1.3.5
└─┬ yo@1.0.0

The strange part for me is if I run yo --help I get a strange list of generators

[?] What would you like to do?
  [ ] Run the Angular generator
  [ ] Run the Foundation generator
  [ ] Run the H5bp generator
  [X] Run the Mocha generator
  [ ] Run the Webapp generator
  [ ] Run the Karma generator
  [ ] Update your generators
  [ ] Install a generator
  [ ] Find some help
  [ ] Get me out of here!

Answer 1

I tried installing Yeoman on an Ubuntu precise32 vagrant vm. I ran into the same problem: Yeoman did not find the generators I installed, although there were no errors during the installation of these generators. Files were in place and permissions seemed alright.

The above solutions didn't work for me.

I ran

yo doctor

to see what was wrong, and as it turned out, the following was the problem:

[Yeoman Doctor] Uh oh, I found potential errors on your machine
---------------

[Error] NPM root value is not in your NODE_PATH
  [info]
    NODE_PATH = /usr/lib/nodejs:/usr/lib/node_modules:/usr/share/javascript
    NPM root  = /home/vagrant/npm/lib/node_modules

  [Fix] Append the NPM root value to your NODE_PATH variable
    Add this line to your .bashrc
      export NODE_PATH=$NODE_PATH:/home/vagrant/npm/lib/node_modules
    Or run this command
      echo "export NODE_PATH=$NODE_PATH:/home/vagrant/npm/lib/node_modules" >> ~/.bashrc && source ~/.bashrc

The fix suggested by the Yeoman Doctor worked as advertised.