fix: set explicit screen when spawning own xvfb

[isnotgood]

• Closes Cypress verify command failing #6184

User facing changelog

Fixes cypress verify crash on some systems caused by not defined -screen.

Additional details

cypress verify crashes in a docker image with this environment:

root@6c2f9da07ecd:/app# uname -a 
Linux 6c2f9da07ecd 4.9.184-linuxkit #1 SMP Tue Jul 2 22:58:16 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
root@6c2f9da07ecd:/app# cat /etc/lsb-release 
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=18.04
DISTRIB_CODENAME=bionic
DISTRIB_DESCRIPTION="Ubuntu 18.04.3 LTS"
root@6c2f9da07ecd:/app# apt list xvfb 
Listing... Done
xvfb/bionic-updates,now 2:1.19.6-1ubuntu4.3 amd64 [installed]
N: There are 2 additional versions. Please use the '-a' switch to see them.
root@6c2f9da07ecd:/app# node -v 
v10.14.2
root@6c2f9da07ecd:/app# ./node_modules/.bin/cypress -v 
Cypress package version: 3.8.2
Cypress binary version: 3.8.2
root@6c2f9da07ecd:/app# file /root/.cache/Cypress/3.8.2/Cypress/Cypress 
/root/.cache/Cypress/3.8.2/Cypress/Cypress: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/l, for GNU/Linux 3.2.0, BuildID[sha1]=5b4fa88bff30493405377c54ef4308de9e5db705, stripped

When I run it with ELECTRON_ENABLE_STACK_DUMPING I get this:

root@6c2f9da07ecd:/app# ELECTRON_ENABLE_STACK_DUMPING=1 ./node_modules/.bin/cypress verify 
It looks like this is your first time using Cypress: 3.8.2

 ✖  Verifying Cypress can run /root/.cache/Cypress/3.8.2/Cypress
   → Cypress Version: 3.8.2
Cypress failed to start.

This is usually caused by a missing library or dependency.

The error below should indicate which dependency is missing.

https://on.cypress.io/required-dependencies

If you are using Docker, we provide containers with all required dependencies installed.

----------

Received signal 11 SEGV_MAPERR fffff4109b7ba15a
#0 0x55720269a3d9 (/root/.cache/Cypress/3.8.2/Cypress/Cypress+0x35d13d8)
r8: 0000000000000000  r9: 00007ffc516aaa30 r10: 00007ffc516aa988 r11: 000000000000000e
r12: 00007ffc516aaadc r13: 00007fa6dfe4f720 r14: fffff4109b7ba12a r15: 00007fa6e1448200
di: 0000000000000000  si: 0000000000000020  bp: 0000000000000000  bx: 00000bedcf1caf20
dx: 0000000000000001  ax: 0000000000000030  cx: 0000000000000001  sp: 00007ffc516aaab0
ip: 00007fa6e142c2dd efl: 0000000000010246 cgf: 002b000000000033 erf: 0000000000000005
trp: 000000000000000e msk: 0000000000000000 cr2: fffff4109b7ba15a
[end of stack trace]
Calling _exit(1). Core file will not be generated.

----------

Platform: linux (Ubuntu Linux - 18.04)
Cypress Version: 3.8.2

Directly running Xvfb and invoking cypress binary from node works well:

root@6c2f9da07ecd:/app# Xvfb :1 -screen 0 1280x800x24 &
[1] 9546
root@6c2f9da07ecd:/app# node -e "require('child_process').spawnSync('/root/.cache/Cypress/3.8.2/Cypress/Cypress', ['--no-sandbox', '--smoke-test', '--ping=89'], { env: { DISPLAY: ':1' }, stdio: 'inherit' });"
It looks like you are running the Cypress binary directly.

This is not the recommended approach, and Cypress may not work correctly.

Please install the 'cypress' NPM package and follow the instructions here:

https://on.cypress.io/installing-cypress
89

Even checked with xwd what is in the framebuffer and all fine.

So I got suspicious Xvfb is not working and added ps aux before and after smoke test is executed and turned out that Xvfb is missing -screen. Not sure if this should not be handled in @cypress/xvfb, up to maintainers.

Feel free to cancel if you already have fix elsewhere.

How has the user experience changed?

Before

After

PR Tasks

• Have tests been added/updated?

[cypress-bot]

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User Experience

• The feature/bugfix is self-documenting from within the product.
• The change provides the end user with a way to fix their problem (no dead ends).

Functionality

• The code works and performs its intended function with the correct logic.
• Performance has been factored in (for example, the code cleans up after itself to not cause memory leaks).
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Internal

• The original issue has been tagged with a release in ZenHub.

[claassistantio]

All committers have signed the CLA.

[isnotgood]

I took this value from freedesktop/xorg-xserver but there has to be something rotten with ubuntu's xvfb, because it's mentioned in man as well as in code that -screen is default to 1280x1024x24 🤔

[isnotgood]

Actually ubuntu uses this packag bionic/xvfb which contains older version with:

#define VFB_DEFAULT_WIDTH      1280
#define VFB_DEFAULT_HEIGHT     1024
#define VFB_DEFAULT_DEPTH         8

So I thought that Electron is freaking out because of the bit depth, but when I start Xvbf with 8bits electron is still fine with that even without -screen at all 🤷‍♂

[isnotgood]

So latest development indicates that it could be problem somewhere else and this is just red herring:

[2031:0121/105922.460578:FATAL:memory.cc(22)] Out of memory. size=65536
We detected that the Chromium Renderer process just crashed.

This is the equivalent to seeing the 'sad face' when Chrome dies.
(...)

Not sure if related thou, because some of our tests pass. Definitely not related, it was /dev/shm set to 16MB

[bahmutov]

I have built cypress/base:ubuntu18-node12.14.1 in cypress-io/cypress-docker-images#211 and verified that this fix solves the problem. Also this fix still works in previous image cypress/base:13.6.0 for example.

[bahmutov]

looks good and solves the problem from my testing

[bahmutov]

Added small unit test in 9ac5fe3

[isnotgood]

Awesome, thank you @bahmutov 🙇