Using tests from test262

[juandopazo]

Hi!

Here are some changes based on the latest spec changes:

• Array operations no longer use ToUint32. Instead, they use ToLength which makes much more sense.
• Uncallable predicates must throw even when the array is empty.

[ljharb]

s/Lose/Loose?

[ljharb]

Can the test262 tests not be brought in as an npm dependency rather than a hardcoded file?

Also, please feel free to look at the es6-shim implementation and verify if it needs any corrections, since you're freshly informed on it.

[juandopazo]

@ljharb I wish we could! Test262 is not based on Mocha. I just wrote a thin wrapper and modified a couple of tests to make it work in Mocha+Node.

[ljharb]

Should this just be length <= 0 to optimize the negative length case?

Also, instead of return undefined;, can this just be return;?

[juandopazo]

Actually, now that the typeof test is done before we could even remove this early exit.

[ljharb]

Sure, it'd be functionally equivalent, but it's nice to optimize for code paths when it's easy :-)

[juandopazo]

Fair enough.

[ljharb]

ping @bterlson @smikes for another use case for npm-runnable test262 tests :-)

[bterlson]

What is needed from bterlson/test262-harness to make it work for this project?

[JakeChampion]

The changes to the implementation have been applied in master:

Array operations no longer use ToUint32. Instead, they use ToLength which makes much more sense.
-- https://github.com/paulmillr/Array.prototype.find/blob/master/implementation.js#L8
Uncallable predicates must throw even when the array is empty.
-- https://github.com/paulmillr/Array.prototype.find/blob/master/implementation.js#L9

[ljharb]

@juandopazo would you mind freshly rebasing this on top of master so it can be reconsidered?