Polyfill for btoa inconsistent with WebApi / Node about edge-runtime

[chetjan]

I think I may have confused the environment of the error. The inconsistency remains, but where it is wrong I got flipped. It seems to be wrong when running the development server locally.

Going with the examples above 'AQID' is produced locally, 'MSwyLDM=' is produced on the server. I don't think it is an issue solely with my development environment, but if others are not able to replicate feel free to close this.

Does the polyfill run locally? I am a bit confused as to why this would happen otherwise.

[Kikobeats]

@chetjan btoa expects a string as input; can you confirm to me it works fine if you do this instead?

btoa(new Uint8Array([1, 2, 3]).toString())

[chetjan]

@Kikobeats Yes, that works fine, but the main issue I'm trying to bring attention to is that the polyfill doesn't match the function it is polyfilling. This can cause unexpected behavior when deploying.

In terms of a test spec, what I would expect to pass would be:

import { btoa as btoaPolyfill } from '@edge-runtime/ponyfill'

test('btoa', async () => {
    const value = new Uint8Array([1, 2, 3])
    expect(btoaPolyfill(value)).toBe(btoa(value))
})

Which I suspect would not pass currently.

It may not be worth fixing, the core-js polyfill looks rather complicated. Alternatively, maybe just throw an error if the input is not a string (then it is clear to the developer that the function expects a string).

[Kikobeats]

@chetjan oh, I can see now your point 👍

How does this look to you? #646

[chetjan]

Looks good! Thanks.