[RRFC] Add nohoist option for workspaces

Motivation ("The Why")

Yarn already supports this option. It makes it possible to work with tooling that expects certain modules to be located in inside the same package that consumes them.

Example

In order for a React Native app to build properly within a monorepo, some packages that react-native depends on must reside inside the node_modules folder within the app package. With yarn, I'm able to accomplish it with this configuration:

  "workspaces": {
    "packages": [
      "api",
      "app",
      "shared/*"
    ],
    "nohoist": [
      // my-app is the name of the package inside the app folder
      "my-app/**"
    ]
  }

How

See: https://classic.yarnpkg.com/blog/2018/02/15/nohoist/

References

• Related to: npm/cli#2036

Start with the workspace and nohoist example in this RFC, then read the linked Yarn no-hoist explanation and related npm/cli#2036 discussion. Define how the option should behave for workspace packages and React Native-style layouts before identifying the npm implementation and tests. Done means the proposal has an agreed design and verified behavior.