cp... permission denied errors for /usr/local/lib/node_modules/npm

[mikestopcontinues]

Describe issue...

On OSX 10.13.1, with n 2.1.7 and base node 9.2.0, when I run n [version], I get a list of cp errors for the entirety of the npm directory.

The new node version is implemented, though the npm version remains at 5.5.1.

cp: /usr/local/lib/node_modules/npm/doc/cli/npm.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-config.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-run-script.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-init.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-completion.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-help.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-logout.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-token.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-bundle.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-prefix.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-profile.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-update.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/cli/npm-root.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/files/npm-shrinkwrap.json.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/files/package.json.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/files/npmrc.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/files/npm-package-locks.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/files/npm-folders.md: Permission denied
cp: /usr/local/lib/node_modules/npm/doc/files/package-lock.json.md: Permission denied
cp: /usr/local/lib/node_modules/npm/.mailmap: Permission denied
cp: /usr/local/lib/node_modules/npm/.travis.yml: Permission denied

Steps to reproduce issue...

1. n latest

Describe the results you expected

Ideally, I always want the most recent version of npm that supports the version of node selected. That said, I mostly just want to stop the errors from appearing.

[shadowspawn]

The default install location on OS X is to a system folder where a normal user does not have write permissions by default. You can strike the same sort of issue when using npm to install global modules. You have three main options:

1. put sudo in front of the command to run as super user
2. change the ownership of the relevant directories to yourself
3. tell n to use a custom location where you do have write permissions (see N_PREFIX)

I prefer option 2 myself.

Some relevant links:
https://docs.npmjs.com/getting-started/fixing-npm-permissions
https://pawelgrzybek.com/fix-priviliges-and-never-again-use-sudo-with-npm/

[mikestopcontinues]

Interesting, @JohnRGee. I'd set NPM_PACKAGES in my .bash_profile (years ago now) to solve the same problem, but it looks like NPM_CONFIG_PREFIX is the new and more robust replacement. I agree though, chowning is the way to go!

Thanks!

[shadowspawn]

I opened a PR to expand the permission coverage in the README based on the above comment: #790