Check 'end' and 'error' events in fromStream()

[novemberborn]

Remove access to private _readableState, which may be missing from third-party stream implementations.

Assumes non-ended streams are passed, in paused mode, in which case end is emitted after read() is called.

Fixes #1.

I realize the commit messages are not in the expected format, but I reckon you can fix that in a squash merge 😉

[reconbot]

Oh sweet, I’ll check it out as soon as I can but it reads really well.

[reconbot]

I don't like this for one reason

Assumes non-ended streams

The reason is no other iterators have this restriction, and I'd rather special case the various kinds of streams than force a different model.

For example

function* numbers () {
  yield 1
  yield 2
  yield 3
}

const nums = numbers()

for (const num of nums) {
  console.log('should print', num)
}

for (const num of nums) {
  console.log(`shouldn't print`, num)
}

However you left the test iterates empty streams and it still passes? It looks like I have to setup CI since the repo moved.

[reconbot]

rebase/merge master and you'll have CI

[novemberborn]

I don't like this for one reason

Assumes non-ended streams

The reason is no other iterators have this restriction, and I'd rather special case the various kinds of streams than force a different model.

Before Node.js 12.9.0 there was no sanctioned API for determining whether a stream had ended. Happy to add that as a check, though this assumption would still apply to non-conformant streams. We could retain the previous check as well, though with some guards to avoid crashes.

I don't see how this relates to other iterators.

you left the test iterates empty streams and it still passes?

That just happens to be how pass-through streams work. The end event isn't actually emitted until you call read(), which we do after hooking up the listener.

[novemberborn]

I've rebased but I'm not sure if GitHub is picking up the CI run. Maybe because this PR predates it. It may work if you push these commits to the main repo.

[reconbot]

Hey sorry this drifted a bit since you opened it. I wasn’t able to reason about it at the time and I’m not sure I like the assumption it requires. So I’m going to close it for now.