Cypress hangs due to xvfb permissions. More intuitive output needed.

[shauvik]

Problem:
On a mac, ./node_modules/cypress-cli/bin/cypress -v was hanging for a coworker.

By tracing, we found that xvfb that cypress uses internally didn't have permissions for creating /tmp/.X11-unix

~/src/mn/projects/fullstory xvfb
_XSERVTransmkdir: ERROR: euid != 0,directory /tmp/.X11-unix will not be created.
_XSERVTransSocketUNIXCreateListener: mkdir(/tmp/.X11-unix) failed, errno = 2
_XSERVTransMakeAllCOTSServerListeners: failed to create listener for local
(EE) 
Fatal server error:
(EE) Cannot establish any listening sockets - Make sure an X server isn't already running(EE) 

Manual Solution:
Run sudo xvfb one time, it will create /tmp/.X11-unix, and after that xvfb can run
And then ./node_modules/cypress-cli/bin/cypress --version doesn’t hang anymore

[jennifer-shehane]

The code for this is done, but this has yet to be released. We'll update the issue and reference the changelog when it's released.

[brian-mann]

Fixed in 0.20.0