Fixes #12956 - Improve cloneFixAttributes function

[markelog]

Events bounded via addEventListener will not be cloned in IE, events bounded via attachEvent will, but in IE9-10, jQuery does not use attachEvent method and even if it did, clear(merge)Attributes hack would not work for those events anyway.

So for new IE, there is no reason to use this hack.

Expando property is not cloned in IE9-10 and it might not exist at all, but removeAttribute method is expensive to use, it would be better to check for existence of expando before trying to remove it.

I would perform clear(merge)Attributes hack only if expando property is exist, but it would affect user events bounded via attachEvent, i'm wondering - is it a real issue?

/cc @dmethvin

[dmethvin]

This makes sense too. We only want to use the clearAttributes/mergeAttributes junk on oldIE.

[markelog]

@dmethvin

We only want to use the clearAttributes/mergeAttributes junk on oldIE

Do you?

From where i'm standing this is not true. If so, and this –

but it would affect user events bounded via attachEvent, i'm wondering - is it a real issue?

is not a problem, you can eliminate clear(merge)Attributes hack altogether, by using detachEvent,
which will speed up cloning process and solve #9646.

[dmethvin]

For IE9 and higher, we use addEventListener for our own needs, so we don't need it there. It's possible that someone is using attachEvent on their own elements in IE and then cloning the element, is that the case you were concerned about? That is really undefined territory. Anything attached directly with either attachEvent or addEventListener is basically something the user would need to worry about.

[rwaldron]

Two things... First, is there a ticket for this? Second, the patch needs to be rebased—Thanks! :)

[markelog]

@rwldrn

First

No, do you need one?

Second

Wait a bit, i will rebase shortly

[rwaldron]

No, do you need one?

We've been over this, yes, please make tickets for bugs/features/changes... everything

[markelog]

We've been over this, yes, please make tickets for bugs/features/changes... everything

Yeah, we did, many times, but i ask because your policy often changes, and sometimes, you push commits without tickets... So, as i understand – de jure i have to, but not de facto.

[markelog]

#12956

[rwaldron]

If you're referring to 4fed8eb, @Krinkle and I discussed this in person and the change itself is trivial.

This still needs to be rebased.

[markelog]

If you're referring to 4fed8eb, @Krinkle and I discussed this in person and the change itself is trivial.

By "you" i did not mean you specifically, i mean team does this – 1, 2, 3, 4...

This still needs to be rebased.

Before i do, i want to try couple of things with this code.

[rwaldron]

1. Doesn't change any jQuery source
2. Doesn't change any jQuery source
3. @dmethvin is the leader of the project and has more understanding of the entire code base then anyone else in the world.
4. I agree that this should've had a ticket.

[markelog]

Doesn't change any jQuery source

So?

@dmethvin is the leader of the project and has more understanding of the entire code base then anyone else in the world.

And?

These examples are not the only one, but never mind, i can create tickets if you like.

[markelog]

@rwldrn Although, if issue is purely with code it would be nice if it was discussed only at github, it's tediously to converse in different places

[rwaldron]

"Github Issues" is inadequate for our needs. I'm not interested in arguing about this any further.

[dmethvin]

I'm not sure what is being argued, but @Orkel has been working on some of these tickets for a while. They just got tangled up with some other pull requests in the same vicinity.

[markelog]

This still needs to be rebased.

done.

It's possible that someone is using attachEvent on their own elements in IE and then cloning the element, is that the case you were concerned about?

Yep.

Anything attached directly with either attachEvent or addEventListener is basically something the user would need to worry about.

OK, then let's try new approach, i added more tests, just in case.

[dmethvin]

So what should we do with gh-1036? Do you want to rebase that after this lands?

[markelog]

@dmethvin

Do you want to rebase that after this lands?

or vice-versa, whatever you decide...

[mikesherov]

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