Error: Cannot find module 'node-zlib-backport' from '.../node_modules/pngjs/lib'

[janusqa]

Current behavior:

Running test with a blink-diff import causes error

Error: Cannot find module 'node-zlib-backport' from '.../cypress-test-tiny-plugin-esm/node_modules/pngjs/lib'

Desired behavior:

Steps to reproduce: (app code and test code)

https://github.com/janusqa/cypress-test-tiny-plugin2-esm

Run test to see error.

Versions

chrome: Version 72.0.3626.121 (Official Build) (64-bit)
linux: Ubuntu 18.04.2 LTS
Cypress package version: 3.1.5
Cypress binary version: 3.1.5

[nym]

Also having this issue.

[jennifer-shehane]

I was able to reproduce the error with the repo provided with Cypress version 3.3.0.

This looks to be a problem from pngjs with browserify which has been fixed https://github.com/lukeapage/pngjs/issues?q=is%3Aissue+sort%3Aupdated-desc+node-zlib-backport+is%3Aclosed a long time ago toriningen/pngjs@9181129

pngjs is a dependency of blink-diff

[email protected] /Users/jennifer/Dev/cypress-test-tiny-plugin2-esm
└─┬ [email protected]
  └─┬ [email protected]
    └── [email protected]

There's a current issue to upgrade pngjs in blink-diff you may want to comment on: yahoo/blink-diff#32 But it looks like their still using the pngjs version from 2016, so not sure.

Someone also mentioned:

I believe you can tell browserify to ignore modules (null them out). Thats what another project using browserify with this package is doing.