Why not auto-detect NPM registry from .npmrc?

I see in discussion from #16 that the OP wanted to install dependencies in a package from a private registry, and the subsequent support for that through the --registry option.

My question is, why does install-peerdeps not work alongside npm (or yarn) by using settings that are already set in ~/.npmrc (or ~/.yarnrc), especially with respect to use of a private NPM registry.

For example, I have published eslint-config-myconfig in my private registry, the URL of which I’ve configured in my ~/.npmrc file. So, if I run this command to query the package’s peer dependencies:

$ npm info eslint-config-myconfig peerDependencies --json
{
  "@typescript-eslint/eslint-plugin": ">=2.21 <3",
  "@typescript-eslint/parser": ">=2.21 <3",
  "eslint": ">=6.8 <7",
  "eslint-config-airbnb-typescript": ">=7 <8",
  "eslint-config-prettier": ">=6.10 <7",
  "eslint-plugin-import": ">=2.20 <3",
  "eslint-plugin-prettier": ">=3.1 <4",
  "eslint-plugin-security": ">=1.4 <2",
  "prettier": ">=1.19 <2",
  "typescript": ">=3.8 <4"
}

It just works!

The same should be true when it comes to installing those peer dependencies. When spawning a child process to run npm (or yarn), just let the underlying package manager read its own configuration file.

[amclin]

I’ll take a look at branching this and see what I come up.

[ljharb]

It could certainly shell out to npm config get registry.