Support for nvm aliases

[AdrieanKhisbe]

Support nvm aliases (including lts/aliases, stable, personal ones, indirections and cycle protection)

Hey @ehmicky 🙂, here is the rework of https://github.com/AdrieanKhisbe/normalize-node-version/commits/support-nvm-aliases--original prototype when #1 was still in building 🏗️. I adapted it to the refactors you made to the project after #1 merge.

Proposed changes:

• Problem addressed: use nvm aliases along with nve
• Related Prs: None
• Solution proposed
  • if NVM_DIR is configured, try to resolve theses aliases.
  • Note: this relies on nvm directory structured, and version files, rather than relying on nvm bash scripts
• Checklist
  • I have read the contribution guidelines.
  • I have added tests (we are enforcing 100% test coverage).
  • I have added documentation in the README.md, the docs directory (if
    any) and the examples directory (if any).
  • The status checks are successful (continuous integration).

[ehmicky]

Thanks a lot for this PR @AdrieanKhisbe!

To keep normalize-node-version focused on Node.js version resolution (and not alias), I created two new projects:

• node-version-alias: resolves any alias from any Node.js version manager
• preferred-node-version: finds the closest .nvmrc, etc. and resolves it using node-version-alias

The dependency chain is now get-node -> preferred-node-version -> node-version-alias -> normalize-node-version -> all-node-versions.

I have integrated all the changes from this PR into those respective projects and credited your changes: nvm custom aliases, LTS named aliases, stable, node, latest.

I have renamed . to now and added the following new features:

• also look into home directory for version files
• supports .n-node-version (used by n version manager)
• supports .nodeenvrc (used by nodeenv version manager)
• supports NODE_VERSION environment variable (used by Netlify)
• supports NODIST_NODE_VERSION environment variable (used by Netlify)
• supports lts and lts/* to target the latest LTS version
• supports lts/-2, lts/-3, etc. to target the n-th latest LTS version (this is a new alias from nvm)
• supports current alias, used by some version managers instead of latest
• supports system, iojs and unstable alias which are some builtin aliases with nvm

The now alias should be able to handle any Node.js version manager file and aliases. However, in order to keep nve simple, only a limited amount of aliases are now allowed in the nve {version} CLI call itself: latest, lts and now. I think this should take care of 99% of use cases and will keep the interface uncomplicated.

Note that the LTS versions are retrieved using nodejs.org/dist/index.json and checking for the lts field instead of looking up the nvm alias directory. This is because:

• the user might not have nvm
• we already retrieve that file for other reasons, so this is cached and faster
• nvm actually does the same under the hood
• this avoids having to specify a NVM_DIR option

Thanks for getting all this progress kicked in!

[AdrieanKhisbe]

Awesome @ehmicky ! =)
and I see nve@11 is out! 🚀

About LTS you're right, it's far better not to rely on nvm for them.

Just one suggestion though,
I would have rather replaced . with here, as "here in the current project".
I feel now does more sound like _, the process current node version.

[ehmicky]

You're absolutely right, here makes more sense than now. I have renamed it in nve@12.