Remove .then wrap from return value of Cypress.Blob.base64StringToBlob

[chrisbreiding]

Current behavior:

We added a .then method to the return value of Cypress.Blob.base64StringToBlob so we could improve the error message when a user attempts to use its old promise-returning API (see this comment). This causes methods like Promise.resolve and Promise.try to think the return value is a thenable, invoking the .then and throwing our error. This makes it difficult to add backwards compatibility without an ugly hack.

Desired behavior:

We shouldn't add on the .then method so that the return value is not mistaken for a promise-returning value. This may just result in a .then is not a function error when using the old API, but that might not be so bad.

Test code to reproduce

it('uses Cypress.Blob.base64StringToBlob', () => {
  return Cypress.Promise.resolve(Cypress.Blob.base64StringToBlob(btoa('foo')))
})

Versions

Cypress 5.0.0

[cypress-bot]

The code for this is done in cypress-io/cypress#8366, but has yet to be released.
We'll update this issue and reference the changelog when it's released.

[cypress-bot]

Released in 5.1.0.

This comment thread has been locked. If you are still experiencing this issue after upgrading to
Cypress v5.1.0, please open a new issue.