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

Bug.

What is the current behavior?

An unlinked (but added) package is missing from node_modules and yarn will not install.

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

1. Link a random package

   git clone [email protected]:tj/co.git
   cd co && yarn link
   

   As a side note, yarn will not install the package's dependencies. The default npm client would do that. I'm not sure whether that's expected or not given that the linking process is slightly different already.

2. Create a new directory and use the linked package from there

   yarn link co
   

3. Add the package again but this time via add

   yarn add co
   

   The linked package is still used at this point (and that's consistent with the default client).

4. Unlink the package

   yarn unlink co
   

   This will remove the link from node_modules as expected.

5. Run yarn to get the added (locked) package back

   yarn
   yarn install v0.15.1
   warning No license field
   success Already up-to-date.
   Done in 0.13s.
   
   ls node_modules
   

   At this point, the package is not present in node_modules but yarn seems to be okay with that and won't install it. Doing yarn add co again will install it.

What is the expected behavior?

The package should be installed after unlinking it and running yarn.

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

Node.js 6.7.0
Yarn 0.15.1
Ubuntu 12.04