Backport input fix

[jquense]

cc @aweary

fixes#7211fixes#6822fixes#6614

we should make sure it doesn't break #3926 any worse (or works with #8438)

[jquense]

CI seems like not my fault :P

[gaearon]

If you added new tests please run ./scripts/fiber/record-tests and commit the result.
It’s how we keep track of Fiber regressions.

[aweary]

@gaearon these tests already exists in master, this PR is open against the 15-dev branch.

[gaearon]

Oops, I didn't realize that.

[jquense]

ping, anything I can do here? I'm not sure what the issue with CI is but it doesn't seem related.

[jquense]

If it helps, there are only a few lines of new code on top of #5746

https://github.com/facebook/react/pull/8575/files#diff-d7d43033e0c4300df2b535a9df27b8edR127

and

https://github.com/facebook/react/pull/8575/files#diff-5e825edec102e25dc133910960c7f37eR325

[aweary]

Sorry for the delay @jquense, I haven't had too much free time unfortunately. I reviewed it and it looks 👍 to me, but haven't actually pulled it down and tested how it might affect #3926 yet

[jquense]

no worries, just wanted to make sure it wasn't blocked by me :)

[gaearon]

@sebmarkbage You wanted to have another look at this?

[aweary]

@jquense Alright, I finally got a chance to verify behavior locally in regards to #3926. Without any changes it doesn't make the issue any worse (still fires before composition event finishes). But I cherry picked ae54338 from #8438 and after minimal changes (making sure nativeEvent was getting passed correctly at a few places) it seems to work. onChange doesn't fire until the composition event ends.

I tested with the native Pinyin keyboard provided by OS X (10.12.2).

I'll continue to look at it and verify that there are no regressions, but I think this looks good 👍

@gaearon@sebmarkbage if either of you want to give it a second review let me know and I can hold off on moving forward with this.

[gaearon]

Does this work with Fiber too?

[aweary]

I'm not super familiar with how Fiber interfaces with the existing event system, but I can switch on the flag and test it out.

[gaearon]

You can see ReactDOMComponent being forked as ReactDOMFiberComponent, the rest of the code is mostly reused. Let me know if you have any specific questions. Thanks!

We’d need Fiber parity to ship.

[aweary]

This change is already in master too btw, so you may have already been testing with it.

[gaearon]

Oooh. I didn’t realize this was against 15-dev, sorry.
Then Fiber parity doesn’t matter that much I guess.

In fact it’s impossible because we haven’t cherry-picked Fiber PRs there at all.

[jquense]

the meat of this is already in and functions with v16, so it should be ok?

If the event marshaling bit here (the code on top of #5746) is a problem for fiber we can remove it. It is convenient but not really needed except to prevent a small but technically breaking change in tests.

[gaearon]

I wonder why CI is failing. Could you rebase? Might be the old version of 15 branch.

[sebmarkbage]

Why is it important to have the getter/setter on the .value/.checked properties? Couldn't we just compare it to React's internal state of the prop?

Is it that you want to protect against manual mutation of the value? What scenario does that happen that is common enough to warrant this?

My concern is that the input value tracker code is:

• Rather big and we'll want to address file size by minimizing code of little used features.
• Complex so it's kind of difficult to follow along and be sure that everything is covered.
• There are attach/detach phases which is not great for Fiber because we explicitly don't have a clean up phase for DOM nodes in most cases and instead rely on GC.
• It can probably be slow to do all that object property descriptor stuff on critical paths like initialization.

I wonder if we could sacrifice one of the edge cases for a smaller solution that only compares to the internal state of the React prop?