Based on #28893.
For other streams we encode each chunk as a separate form field which is
a bit bloated. Especially for binary chunks since they also have an
indirection. We need some way to encode the chunks as separate anyway.
This way the streaming using busboy actually allows each chunk to stream
in over the network one at a time.
For binary streams the actual chunking is not important. The chunks can
be split and recombined in whatever size chunk makes sense.
Since we buffer the entire content anyway we can combine the chunks to
be consecutive. This PR does that with binary streams and also combine
them into a single Blob. That way there's no extra overhead when passing
through a binary stream.
Ideally, we'd be able to just use the stream from that one Blob but
Node.js doesn't return byob streams from Blob. Additionally, we don't
actually stream the content of Blobs due to the layering with busboy
atm. We could do that for binary streams in particular by replacing the
File layering with a stream and resolving each chunk as it comes in.
That could be a follow up.
If we stop buffering in the future, this set up still allows us to split
them and send other form fields in between while blocked since the
protocol is still the same.
Follow-up to https://github.com/facebook/react/pull/28813.
RDT is using `typeOf` from `react-is` to determine the element display
name, I've forked an implementation of this method, but will be using
legacy element symbol.
## Summary
Exposes the APIs needed by React Native DevTools (Fusebox) to implement
the "view element source" and "view attribute source" features.
## How did you test this change?
1. `yarn build` in `react-devtools-fusebox`
2. Copy artifacts to rn-chrome-devtools-frontend
3. Write some additional glue code to implement
`viewElementSourceFunction` in our CDT fork.
4. Test the feature manually.
https://github.com/facebook/react/assets/2246565/12667018-100a-4b3f-957a-06c07f2af41a
## Summary
This PR introduces Fabric-only version of
`ReactNativeAttributesPayload`. It is a copy-paste of
`ReactNativeAttributesPayload.js`, and is called
`ReactNativeAttributesPayloadFabric.js`.
The idea behind this change is that certain optimizations in prop
diffing may actually be a regression on the old architecture. For
example, removing custom diffing may result in larger updateProps
payloads. Which is, I guess, fine with JSI, but might be a problem with
the bridge.
## How did you test this change?
There should be no runtime effect of this change.
## Summary
Sets up dynamic feature flags for `disableStringRefs`, `enableFastJSX`,
and `enableRefAsProp` in React Native (at Meta).
## How did you test this change?
```
$ yarn test
$ yarn flow fabric
```
In order to integrate the `react-reconciler` build created in #28880
with third party libraries, we need to have matching
`react-reconciler/constants` to go with it.
Same as #28847 but in the other direction.
Like other promises, this doesn't actually stream in the outgoing
direction. It buffers until the stream is done. This is mainly due to
our protocol remains compatible with Safari's lack of outgoing streams
until recently.
However, the stream chunks are encoded as separate fields and so does
support the busboy streaming on the receiving side.
We currently don't test FormData / File dependent features in CI because
we use an old Node.js version in CI. We should probably upgrade to 18
since that's really the minimum version that supports all the features
out of the box.
JSDOM is not a faithful/compatible implementation of these APIs. The
recommended way to use Flight together with FormData/Blob/File in older
Node.js versions, is to polyfill using the `undici` library.
However, even in these versions the Blob implementation isn't quite
faithful so the Reply client needs a slight tweak for multi-byte typed
arrays.
Stacked on #28798.
Add another AsyncLocalStorage to the FlightServerConfig. This context
tracks data on a per component level. Currently the only thing we track
is the owner in DEV.
AsyncLocalStorage around each component comes with a performance cost so
we only do it DEV. It's not generally a particularly safe operation
because you can't necessarily associate side-effects with a component
based on execution scope. It can be a lazy initializer or cache():ed
code etc. We also don't support string refs anymore for a reason.
However, it's good enough for optional dev only information like the
owner.
Bundle config: inline internal hook wrapper
Instead of reading this wrapper from 2 files for "start" and "end" and
then string modifying the templates, just inline them like the other
wrappers in this file.
## Summary
Enables the inspected element context menu in React Native DevTools
(Fusebox).
## How did you test this change?
1. `yarn build` in `react-devtools-fusebox`
2. Copy artifacts to rn-chrome-devtools-frontend
3. Manually test the context menu
https://github.com/facebook/react/assets/2246565/b35cc20f-8d67-43b0-b863-7731e10fffac
NOTE: The serialised values sometimes expose React internals (e.g. Hook
data structures instead of just the values), but that seems to be a
problem equally on web, so I'm going for native<->web parity here.
Following #28768, add a path to testing Fast JSX on www.
We want to measure the impact of Fast JSX and enable a path to testing
before string refs are completely removed in www (which is a work in
progress).
Without `disableStringRefs`, we need to copy any object with a `ref` key
so we can pass it through `coerceStringRef()` and copy it into the
object. This de-opt path is what is gated behind
`enableFastJSXWithStringRefs`.
The additional checks should have no perf impact in OSS as the flags
remain true there and the build output is not changed. For www, I've
benchmarked the addition of the boolean checks with values cached at
module scope. There is no significant change observed from our
benchmarks and any latency will apply to test and control branches
evenly. This added experiment complexity is temporary. We should be able
to clean it up, along with the flag checks for `enableRefAsProp` and
`disableStringRefs` shortly.
## Summary
This PR introduces a faster version of the `addProperties` function.
This new function is basically the `diffProperties` with `prevProps` set
to `null`, propagated constants, and all the unreachable code paths
collapsed.
## How did you test this change?
I've tested this change with [the benchmark
app](https://github.com/react-native-community/RNNewArchitectureApp/tree/new-architecture-benchmarks)
and got ~4.4% improvement in the view creation time.
When a React PR is opened CI will report large size changes. But for
critical packages like react-dom it reports always. In React 19 we moved
the build for react-dom the client reconciler from react-dom to
react-dom/client
This change adds react-dom-client artifacts for stable and oss channels
since that is originally what was being tracked. But since
react-dom/client always imports react-dom I left the original react-dom
packages as critical as well. They are small but it would be good to
keep an eye on them
## Summary
I'm looking at cleaning up some unnecessary manual property flattening
in React Native and wanted to verify this behaviour is working as
expected, where properties from nested objects will always overwrite
properties from the base object.
## How did you test this change?
Unit tests
Rebasing and landing https://github.com/facebook/react/pull/28798
This PR was approved already but held back to give time for the sync.
Rebased and landing here without pushing to seb's remote to avoid
possibility of lost updates
---------
Co-authored-by: Sebastian Markbage <sebastian@calyptus.eu>
It turns out we already made refs writable in #25696, which has been in
canary for over a year. The approach in that PR also has the benefit of
being slightly more perf sensitive because it still uses a shared object
until the fiber is mounted. So let's just go back to that.
Add new reconciler methods since last breaking change to the README
based on usage and comments.
---------
Co-authored-by: Josh Story <josh.c.story@gmail.com>
This PR reorganizes the `react-dom` entrypoint to only pull in code that
is environment agnostic. Previously if you required anything from this
entrypoint in any environment the entire client reconciler was loaded.
In a prior release we added a server rendering stub which you could
alias in server environments to omit this unecessary code. After landing
this change this entrypoint should not load any environment specific
code.
While a few APIs are truly client (browser) only such as createRoot and
hydrateRoot many of the APIs you import from this package are only
useful in the browser but could concievably be imported in shared code
(components running in Fizz or shared components as part of an RSC app).
To avoid making these require opting into the client bundle we are
keeping them in the `react-dom` entrypoint and changing their
implementation so that in environments where they are not particularly
useful they do something benign and expected.
#### Removed APIs
The following APIs are being removed in the next major. Largely they
have all been deprecated already and are part of legacy rendering modes
where concurrent features of React are not available
* `render`
* `hydrate`
* `findDOMNode`
* `unmountComponentAtNode`
* `unstable_createEventHandle`
* `unstable_renderSubtreeIntoContainer`
* `unstable_runWithPrioirty`
#### moved Client APIs
These APIs were available on both `react-dom` (with a warning) and
`react-dom/client`. After this change they are only available on
`react-dom/client`
* `createRoot`
* `hydrateRoot`
#### retained APIs
These APIs still exist on the `react-dom` entrypoint but have normalized
behavior depending on which renderers are currently in scope
* `flushSync`: will execute the function (if provided) inside the
flushSync implemention of FlightServer, Fizz, and Fiber DOM renderers.
* `unstable_batchedUpdates`: This is a noop in concurrent mode because
it is now the only supported behavior because there is no legacy
rendering mode
* `createPortal`: This just produces an object. It can be called from
anywhere but since you will probably not have a handle on a DOM node to
pass to it it will likely warn in environments other than the browser
* preloading APIS such as `preload`: These methods will execute the
preload across all renderers currently in scope. Since we resolve the
Request object on the server using AsyncLocalStorage or the current
function stack in practice only one renderer should act upon the
preload.
In addition to these changes the server rendering stub now just rexports
everything from `react-dom`. In a future minor we will add a warning
when using the stub and in the next major we will remove the stub
altogether
This removes the automatic patching of the global `fetch` function in
Server Components environments to dedupe requests using `React.cache`, a
behavior that some RSC framework maintainers have objected to.
We may revisit this decision in the future, but for now it's not worth
the controversy.
Frameworks that have already shipped this behavior, like Next.js, can
reimplement it in userspace.
I considered keeping the implementation in the codebase and disabling it
by setting `enableFetchInstrumentation` to `false` everywhere, but since
that also disables the tests, it doesn't seem worth it because without
test coverage the behavior is likely to drift regardless. We can just
revert this PR later if desired.
Used this test scenario to clarify how callback refs work when detached
based on the availability of a cleanup function to update documentation
in https://github.com/reactjs/react.dev/pull/6770
Checking it in for additional test coverage and test-based documentation
Stacked on #28849, #28854, #28853. Behind a flag.
If you're following along from the side-lines. This is probably not what
you think it is.
It's NOT a way to get updates to a component over time. The
AsyncIterable works like an Iterable already works in React which is how
an Array works. I.e. it's a list of children - not the value of a child
over time.
It also doesn't actually render one component at a time. The way it
works is more like awaiting the entire list to become an array and then
it shows up. Before that it suspends the parent.
To actually get these to display one at a time, you have to opt-in with
`<SuspenseList>` to describe how they should appear. That's really the
interesting part and that not implemented yet.
Additionally, since these are effectively Async Functions and uncached
promises, they're not actually fully "supported" on the client yet for
the same reason rendering plain Promises and Async Functions aren't.
They warn. It's only really useful when paired with RSC that produces
instrumented versions of these. Ideally we'd published instrumented
helpers to help with map/filter style operations that yield new
instrumented AsyncIterables.
The way the implementation works basically just relies on unwrapThenable
and otherwise works like a plain Iterator.
There is one quirk with these that are different than just promises. We
ask for a new iterator each time we rerender. This means that upon retry
we kick off another iteration which itself might kick off new requests
that block iterating further. To solve this and make it actually
efficient enough to use on the client we'd need to stash something like
a buffer of the previous iteration and maybe iterator on the iterable so
that we can continue where we left off or synchronously iterate if we've
seen it before. Similar to our `.value` convention on Promises.
In Fizz, I had to do a special case because when we render an iterator
child we don't actually rerender the parent again like we do in Fiber.
However, it's more efficient to just continue on where we left off by
reusing the entries from the thenable state from before in that case.
We have changed the shape (and the runtime) of React Elements. To help
avoid precompiled or inlined JSX having subtle breakages or deopting
hidden classes, I renamed the symbol so that we can early error if
private implementation details are used or mismatching versions are
used.
Why "transitional"? Well, because this is not the last time we'll change
the shape. This is just a stepping stone to removing the `ref` field on
the elements in the next version so we'll likely have to do it again.
Stacked on #28853 and #28854.
React supports rendering `Iterable` and will soon support
`AsyncIterable`. As long as it's multi-shot since during an update we
may have to rerender with new inputs an loop over the iterable again.
Therefore the `Iterator` and `AsyncIterator` types are not supported
directly as a child of React - and really it shouldn't pass between
Hooks or components neither for this reason. For parity, that's also the
case when used in Server Components.
However, there is a special case when the component rendered itself is a
generator function. While it returns as a child an `Iterator`, the React
Element itself can act as an `Iterable` because we can re-evaluate the
function to create a new generator whenever we need to.
It's also very convenient to use generator functions over constructing
an `AsyncIterable`. So this is a proposal to special case the
`Generator`/`AsyncGenerator` returned by a (Async) Generator Function.
In Flight this means that when we render a Server Component we can
serialize this value as an `Iterable`/`AsyncIterable` since that's
effectively what rendering it on the server reduces down to. That way if
Fiber can receive the result in any position.
For SuspenseList this would also need another special case because the
children of SuspenseList represent "rows".
`<SuspenseList><Component /></SuspenseList>` currently is a single "row"
even if the component renders multiple children or is an iterator. This
is currently different if Component is a Server Component because it'll
reduce down to an array/AsyncIterable and therefore be treated as one
row per its child. This is different from `<SuspenseList><Component
/><Component /></SuspenseList>` since that has a wrapper array and so
this is always two rows.
It probably makes sense to special case a single-element child in
`SuspenseList` to represent a component that generates rows. That way
you can use an `AsyncGeneratorFunction` to do this.