Uncaught SyntaxError: Invalid or unexpected token happening out of nowhere in CI/CD

Current behavior:

All of a sudden, out of nowhere, all of my Cypress tests are failing when run in CircleCI, with the following:

Uncaught SyntaxError: Invalid or unexpected token

This error originated from your application code, not from Cypress.

When Cypress detects uncaught errors originating from your application it will automatically fail the current test.

This behavior is configurable, and you can choose to turn this off by listening to the 'uncaught:exception' event.

https://on.cypress.io/uncaught-exception-from-application

Because this error occurred during a 'before each' hook we are skipping the remaining tests in the current suite: 'Coupons'

This is happening across multiple Angular projects. I have no idea where to begin to even pinpoint the issue - when I run Cypress via cypress open, all of my tests run fine.

I’m suspicious it’s one of the npm packages I updated in between deploys, so here’s the package.json DIFF:

Desired behavior:

The builds should run properly both in headless mode in CircleCI and locally. If that doesn’t work, at least give me more info so I can chase down the issue.

Steps to reproduce: (app code and test code)

• I check in my code
• CircleCI picks up the change and runs it
• I get the aforementioned error in the Cypress dashboard

This just started today.

Versions

Cypress 3.4.1, Chrome 65

[mitschmidt]

Encountered the same issue and solved it by using this approach: https://github.com/cypress-io/cypress/issues/4042#issuecomment-487562075

[andrewryan1906]

" But, there’s no evidence that this is an issue with Cypress,"

Guys; if Cypress works for weeks at a time, and then all of a sudden starts spitting out this error, ONLY in CircleCI, and with no other information that can help me understand what the problem is or begin to troubleshoot, then it is BY DEFINITION an issue with Cypress. At the very least, I think it reasonable for the tool to provide helpful information that would allow me to start to locate the issue.

And - the fact that I cannot reproduce it locally is highly suspect.

Perhaps you’ve encountered this before? Or some hints or where it could be? I have about 200 packages… removing them 1 at a time to get to the bottom of this is not an ideal solution.