june-30.md

July 4, 2016 · View on GitHub

June 30 (discuss)

If you missed what Fiber is, look here.
Not very exciting.. but it can render a <div>!
Basically this is all that Sebastian showed us so far.
You can find the demo here but you’d need to compile React DOM to point to the fiber version.

We are moving towards not using createClass in the internal Facebook components.
Keyan is working on an open source codemod to automate the transition.
The codemod converts createClass calls to ES classes with experimental property initializers proposal and Flow.
We don’t officially recommend this yet because the proposal has not advanced yet but we want to dogfood it internally.
There are more things to figure out with Flow (e.g. we might need to annotate state properties).
Dan ran the codemod that removes one very common mixin we had, so now we have more convertible classes.
It is essential that we add some version of PureComponent to React because a lot of components use PureRenderMixin.

#### Naming

We’ve been assuming we’d call it React.PureComponent.
However “pure” really means something different in computer science.
What we try to express is that component props are immutable so the output is safe to memoize.
Other suggestions: MemoizedComponent, MemoizableComponent.
It’s hard to spell!
We don’t want people to use it everywhere so more complicated name might be fine.
We can bikeshed on this forever.

It seems that proposed heuristic generated a lot of confusion and potential issues.
We can drop the heuristic from the proposal and just get the class in. Then decide later.

After the internal createClass deprecation, can we drop the addons?
We haven’t been maintaining ReactTransitionGroup and other addons well.
We should transfer ownership to folks that are actually relying on them.
Almost everything can be decoupled except Perf and TestUtils.
This should happen before flat bundling.
Should we move React.createFragment into React?
- No, this was an upgrade path, shouldn’t need to use it anymore.
- It could have been the way you specify render methods without a single return value but we didn’t implement this.
Paul and Dan will come up with a plan for each addon.

It is popular in the community but the last stable version doesn’t work with functional components.
There is a new version that solves these problems but it isn’t quite stable yet.
Dan will take a week to fix a few issues and release a stable version with docs.

Paul planned to release today.
Dan noticed it would be better to deduplicate the new DOM unknown attribute warning.
We will let the community fix it and then cut 15.2.0.
Jim wrote about the reasons and the strategies for fixing this warning in the related gist.
Some useful discussions about this change: erikras/redux-form#1249, Hacker0x01/react-datepicker#517.
We won’t do a blog post about this release (and about most patch and minor releases in general).
Instead, you can find changes in the changelog.

Please feel free to discuss these notes in the corresponding pull request.