Deadlock building fresh dependencies caused by error looking up modules

[calavera]

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

This is a bug

What is the current behavior?

There is a deadlock building fresh dependencies when yarn fails to load modules. There are other similar reported errors, but I'm not sure if the cause is the same, so I opened a new issue:

#2142
#1981

I'm attaching a screenshot so you can see the state when Yarn is locked:

Steps to reproduce:

1. Clone a test repo I put together for you:

git clone https://github.com/calavera/test-yarn-scripts

2. Run the script script/test-build.sh:

script/test-build.sh https://github.com/netlify/netlify-cms "npm run build"

That script uses Docker to isolate what's downloading from the internet inside a container, but you can reproduce it without Docker, the code is pretty straightforward.

What is the expected behavior?

Dependencies to install, or Yarn to fail when there is an error 😸

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

The project downloaded with test-build uses Node 4.7.0, but I've seen similar behavior with 6.9.1. Yarn's version is 0.18.0. The container uses an Ubuntu 14.04 image.