Andrew Clark
9d67847f7b
* Minor test refactor: `resolveText`
Adds a `resolveText` method as an alternative to using timers. Also
removes dependency on react-cache (for just this one test file; can do
the others later).
Timer option is still there if you provide a `ms` prop.
* Bugfix: Dropped updates in suspended tree
When there are multiple updates at different priority levels inside
a suspended subtree, all but the highest priority one is dropped after
the highest one suspends.
We do have tests that cover this for updates that originate outside of
the Suspense boundary, but not for updates that originate inside.
I'm surprised it's taken us this long to find this issue, but it makes
sense in that transition updates usually originate outside the boundary
or "seam" of the part of the UI that is transitioning.
* Bugfix: Suspense fragment skipped by setState
Fixes a bug where updates inside a suspended tree are dropped because
the fragment fiber we insert to wrap the hidden children is not part of
the return path, so it doesn't get marked during setState.
As a workaround, I recompute `childExpirationTime` right before deciding
to bail out by bubbling it up from the next level of children.
This is something we should consider addressing when we refactor the
Fiber data structure.
* Add back `lastPendingTime` field
This reverts commit 9a541139df.
I want to use this so we can check if there might be any lower priority
updates in a suspended tree.
We can remove it again during the expiration times refactor.
* Use `lastPendingTime` instead of Idle
We don't currently have an mechanism to check if there are lower
priority updates in a subtree, but we can check if there are any in the
whole root. This still isn't perfect but it's better than using Idle,
which frequently leads to redundant re-renders.
When we refactor `expirationTime` to be a bitmask, this will no longer
be necessary because we'll know exactly which "task bits" remain.
* Add a test for updating the fallback
React · 
React is a JavaScript library for building user interfaces.
- Declarative: React makes it painless to create interactive UIs. Design simple views for each state in your application, and React will efficiently update and render just the right components when your data changes. Declarative views make your code more predictable, simpler to understand, and easier to debug.
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Examples
We have several examples on the website. Here is the first one to get you started:
function HelloMessage({ name }) {
return <div>Hello {name}</div>;
}
ReactDOM.render(
<HelloMessage name="Taylor" />,
document.getElementById('container')
);
This example will render "Hello Taylor" into a container on the page.
You'll notice that we used an HTML-like syntax; we call it JSX. JSX is not required to use React, but it makes code more readable, and writing it feels like writing HTML. If you're using React as a <script> tag, read this section on integrating JSX; otherwise, the recommended JavaScript toolchains handle it automatically.
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Good First Issues
To help you get your feet wet and get you familiar with our contribution process, we have a list of good first issues that contain bugs which have a relatively limited scope. This is a great place to get started.
License
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