Incompatibility with npm5 when run yarn add file:FolderName

[brenordr]

Do you want to request a feature or report a bug?
bug

What is the current behavior?
Incompatibility with npm 5.

consider the following package.json (reduced for brevity)

{
  "name": "my-project",
  "description": "my project",
  "main": "index.js",
  "dependencies": {
      "my_local_lib": "file:LocalLib"
   }
}

with npm 5 the lib "my_local_lib" is installed as a symlink
but yarn install it as copy of the folder LocalLib

If the current behavior is a bug, please provide the steps to reproduce.

1. create a new project
2. create a sub project (folder named FolderX with a package.json)
3. yarn add FolderX
4. yarn install

What is the expected behavior?
create a symlink of FolderX

Please mention your node.js, yarn and operating system version.
node v8.4.0
yarn v0.27.5
macOS 10.12.6

[webmobiles]

why yarn need npm? if i do npm install -g [email protected] to downgrand from npm5 is ok? it's not yarn independent from npm?

[BYK]

Looks like this was an unannounced change: http://codetunnel.io/npm-5-changes-to-npm-link/

I'm not sure if changing the file: protocol's behavior to be link: is a good idea. Why do you need it?

[BYK]

@webmobiles I think your comment is misplaced?

[arcanis]

Yeah we decided against implementing this change at the time we started working on the link protocol. Even now I'm not sure we should follow it; if you actually want to copy the files you would have no way of doing it.

[arcanis]

The NPM issue: npm/npm#15900

[briandipalma]

This makes monorepos nicer to work with when using npm. With npm 4 and yarn a change to a local dependency means you have to reinstall. You can link but it's nice to get the same behaviour out of the box with all your dependencies.

[webmobiles]

@BYK when i install "yarn global create-react-native-app" and npm5 installed does not work to create projects, then i downgrade to v4:
npm install -g [email protected] , and then:
npm -g install create-react-native-app

but when i create the project:

create-react-native-app myproj

yarn is called, yarn works underhood npm version ? that is my question , about yarn and npm5 or npm4 together, thanks

[BYK]

We do not have plans for implementing this for now so closing the issue.

@webmobiles I cannot figure out what the issue might be from your comment but it doesn't sound related to this issue so feel free to file a new issue with more details about how to reproduce it.