fix: buffer check for jest

[timsuchanek]

Closes #318

[ronag]

Could you add a isBuffer in util instead?

function isBuffer (buffer) {
  // See, https://github.com/mcollina/undici/pull/319
  return buffer instanceof Uint8Array || Buffer.isBuffer(buffer)
}

and replace all occurrences of instanceof Uint8Array with it?

[timsuchanek]

Yep will do

[timsuchanek]

Done

[mcollina]

I'm totally lost on why Buffer.isBuffer would work, but hey.

[ronag]

Related? jestjs/jest#9983

[ronag]

jestjs/jest#9993

[ronag]

https://github.com/facebook/jest/blob/4bd3d4a05999170f423f7050d4e0537648499e88/packages/jest-environment-jsdom/src/index.ts#L49

[jimmywarting]

Shouldn't it be enough to do instanceof Uint8Array?
Buffer is a instanceof Uint8Array after all...

[mcollina]

lgtm