Proposal: insert fixes for basic errors right from the Test Runner

[bahmutov]

Background

I have shown Cypress Test Runner at a company where my friend works, and then had to wait in their office for an hour until the end of the work day. While sitting at one of the desks, I have noticed a person next to me writing a Cypress test - trying it out on their website. He is a front end developer, who loved the demo and immediately wanted to replace a few existing tests.

Their site polyfills fetch which caused Cypress test to crash due to XMLHttpRequest property missing (when we try to wrap it for XHR stubbing). I saw his reaction - he clicked on the link in the error message https://on.cypress.io/uncaught-exception-from-application which took him to this doc

He did NOT follow the link. I was next to him so I jumped into the situation, clicking on the link and explaining to him what happens. The first event on the page shows the workaround

Without me there observing it, he would be blocked. After we added the workaround, he wrote several tests, absolutely happy as a clam

Proposal

We know the spec, we know the place with cy.visit, we show the specific error message. We could add a button to the error message with something like "Add workaround". When the user clicks it, we can add our handler to the spec file.

Cypress.on('uncaught:exception', (err, runnable) => {
  // returning false here prevents Cypress from
  // failing the test due to uncaught exceptions from the production code
  return false
})

We could even target the handler by only handling that specific error

The purpose is not to create a universal solution, but to avoid people being blocked 100% when they try writing their first "hello Cypress" test. We could probably insert typical solution for

• uncaught exception from the website under test
• chrome security: false
• ignore missing content type or non-200 response from the server

Related

I think this work can only happen after the in progress error improvements land (issue #3762, pull request #3930)

[mccataldo]

@bahmutov I think this error also could apply:

CypressError: Invalid alias: 'someAlias'.
You forgot the '@'. It should be written as: '@someAlias'

[bahmutov]

Yeah that’s a good candidate!

…

Sent from my iPhone

On Jun 26, 2019, at 13:21, mike cataldo ***@***.***> wrote: @bahmutov I think this error also could apply: CypressError: Invalid alias: 'someAlias'. You forgot the '@'. It should be written as: ***@***.***' — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.