Named dependency groups

[sandstrom]

I'd suggest that NPM adopted named dependency groups.

It could work like this:

• dependencies -> production group [existing group]
• devDependencies -> dev group [existing group]
• lintingDependencies -> linting group [example]

The general pattern would be this:

{prefix}Dependencies -> {prefix} group

These groups could then be used with install, e.g. npm install only=linting or npm install only=dev,test.

Prior Art

Bundler (a Ruby package manager) has support for groups:
https://bundler.io/guides/groups.html

Use-case

A common problem today is that linting (in CI jobs) need to install a ton of dependencies that aren't needed. If we could have a linting group, we could install only select dependencies needed to run linting.

One can imagine similar groups for tests, deployment and staging.

Open-questions

• It could make sense to use dependencies as the default group (basically changing it's name), but that would be a breaking change.

Alternative solutions

One could also allow specifying an alternative package file when calling npm install, for example npm install --package-file=linting-package.json (prior art).

[Delapouite]

Hi. This issue seems closely related to this previous one about custom dependency lists: #360