Yarn: Yarn fails to install public scoped packages when _auth is defined in .npmrc

[AzGoalie]

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

What is the current behavior?
Yarn fails to find scoped packages when _auth is defined in .npmrc.

If the current behavior is a bug, please provide the steps to reproduce.
Sample repository located: https://github.com/AzGoalie/public-scope-yarn-install-failure
Create a project with a package.json and .npmrc
Add "@turf/turf": "3.4.1" to dependencies in package.json
Add always-auth=false and _auth=fake-auth-token to .npmrc
Run yarn install

What is the expected behavior?
Yarn should install the scoped package.

Please mention your node.js, yarn and operating system version.

Yarn version: 
  0.18.1

Node version: 
  7.4.0

Platform: 
  win32 x64

[enriquecaballero]

I have the exact same thing happening to me with the exact same package.

[enriquecaballero]

I was able to fix this by setting always-auth to true. Running yarn v0.21.3; installed via Homebrew. Nevermind. Once I set that to true it complained about babel-polyfill ...

[tautvilas]

I have same issue. If I have _auth token in .npmrc I can not successfully excecute create-react-native-app. yarn fails with 403 on expo dependencies/users.