stream: initial port of test262 tests

[benjamingr]

This adds some test262 tests from tc39/test262#2818 to Node's implementation of iterator-helpers + a few fixes.

I want to do this in batches since it will probably require a bunch of changes (this one just adds the ones for asIndexedPairs and drop as they make sense).

cc @nodejs/streams @ljharb @rwaldron (sorry for the no context ping Rick! thought I'd give you a heads up we're going to use all of these we can unless there is something else I should be aware of!)

[nodejs-github-bot]

Review requested:

• @nodejs/streams

[ljharb]

Why copy paste the tests instead of running test262 directly?

[benjamingr]

@ljharb well - few reasons:

• Node typically doesn't implement TC39 features so I'm not aware of infrastructure to do this. I don't expect this to be a common occurrence as anything that can come from the language directly (and v8) should.
• We're not actually implementing the spec de-jure here since the spec speaks of AsyncIterators and Iterators and we're adding this methods on Readable streams.
• A bunch of them aren't really relevant (e.g. stuff that isn't relevant to streams because of backpressure like the timing of exceptions when you subclass an AsyncIterator with a custom get).

Though this is mostly just my intuition and I recently started - it's possible there is a way to run test262 tests in Node I'm not aware of and to somehow tell it to use a different object with construction methods (like Readable.from instead of AsyncIterator.from) and exclude specific tests but that seemed like a lot more work than just porting them and checking every few months what changed and porting that.

[ljharb]

@benjamingr those are good points. i think it'd be useful if test262 allowed you to point the tests at an arbitrary object - but the only way to do it now would probably be to use vm and hack together a fake global, so you could exercise the tests. Copypasting seems fine then ¯\_(ツ)_/¯

[benjamingr]

Moving to draft to not trigger many github cis

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/42252/

[benjamingr]

@mcollina @ronag any chance this can get a review? It's just adding tests + some esoteric behavior changes (like the .length and .name properties of the methods) to match the spec

[benjamingr]

@nodejs/streams ping

[jasnell]

This arguably should be added to LICENSE instead with a comment here indicating that's where the relevant license info is located. But not blocking.

[nodejs-github-bot]

Landed in 662fb5f

[danielleadams]

@benjamingr when pulling in for the v16 for a patch release, this breaks the build. I am not sure if this is dependent on a semver minor change, or needs a backport - do you mind taking a look? Thank you.

[benjamingr]

@danielleadams it depends on a previous semver-major patch (adding these methods).

[danielleadams]

@benjamingr got it. thanks!