This is similar to #28771 but for isomorphic. We need a make over for
these dispatchers anyway so this is the first step. Also helps flush out
some internals usage that will break anyway.
It flattens the inner mutable objects onto the ReactSharedInternals.
Currently updatePriority is tracked in the reconciler. `flushSync` is
going to be implemented reconciler agnostic soon and we need to move the
tracking of this state to the renderer and out of reconciler. This
change implements new renderer bin dings for getCurrentUpdatePriority
and setCurrentUpdatePriority.
I was originally going to have the getter also do the event priority
defaulting using window.event so we eliminate getCur rentEventPriority
but this makes all the callsites where we store the true current
updatePriority on the stack harder to work with so for now they remain
separate.
I also moved runWithPriority to the renderer since it really belongs
whereever the state is being managed and it is only currently exposed in
the DOM renderer.
Additionally the current update priority is not stored on
ReactDOMSharedInternals. While not particularly meaningful in this
change it opens the door to implementing `flushSync` outside of the
reconciler
This implements the concept of a DEV-only "owner" for Server Components.
The owner concept isn't really super useful. We barely use it anymore,
but we do have it as a concept in DevTools in a couple of cases so this
adds it for parity. However, this is mainly interesting because it could
be used to wire up future owner-based stacks.
I do this by outlining the DebugInfo for a Server Component
(ReactComponentInfo). Then I just rely on Flight deduping to refer to
that. I refer to the same thing by referential equality so that we can
associate a Server Component parent in DebugInfo with an owner.
If you suspend and replay a Server Component, we have to restore the
same owner. To do that, I did a little ugly hack and stashed it on the
thenable state object. Felt unnecessarily complicated to add a stateful
wrapper for this one dev-only case.
The owner could really be anything since it could be coming from a
different implementation. Because this is the first time we have an
owner other than Fiber, I have to fix up a bunch of places that assumes
Fiber. I mainly did the `typeof owner.tag === 'number'` to assume it's a
Fiber for now.
This also doesn't actually add it to DevTools / RN Inspector yet. I just
ignore them there for now.
Because Server Components can be async the owner isn't tracked after an
await. We need per-component AsyncLocalStorage for that. This can be
done in a follow up.
Saves some bytes and ensures that we're actually disabling it.
Turns out this flag wasn't disabling React Native/Fabric, React Noop and
React ART legacy modes so those are updated too.
Should be rebased on #28681.
Stacked on #28627.
This makes error logging configurable using these
`createRoot`/`hydrateRoot` options:
```
onUncaughtError(error: mixed, errorInfo: {componentStack?: ?string}) => void
onCaughtError(error: mixed, errorInfo: {componentStack?: ?string, errorBoundary?: ?React.Component<any, any>}) => void
onRecoverableError(error: mixed, errorInfo: {digest?: ?string, componentStack?: ?string}) => void
```
We already have the `onRecoverableError` option since before.
Overriding these can be used to implement custom error dialogs (with
access to the `componentStack`).
It can also be used to silence caught errors when testing an error
boundary or if you prefer not getting logs for caught errors that you've
already handled in an error boundary.
I currently expose the error boundary instance but I think we should
probably remove that since it doesn't make sense for non-class error
boundaries and isn't very useful anyway. It's also unclear what it
should do when an error is rethrown from one boundary to another.
Since these are public APIs now we can implement the
ReactFiberErrorDialog forks using these options at the roots of the
builds. So I unforked those files and instead passed a custom option for
the native and www builds.
To do this I had to fork the ReactDOMLegacy file into ReactDOMRootFB
which is a duplication but that will go away as soon as the FB fork is
the only legacy root.
Stacked on top of #28498 for test fixes.
### Don't Rethrow
When we started React it was 1:1 setState calls a series of renders and
if they error, it errors where the setState was called. Simple. However,
then batching came and the error actually got thrown somewhere else.
With concurrent mode, it's not even possible to get setState itself to
throw anymore.
In fact, all APIs that can rethrow out of React are executed either at
the root of the scheduler or inside a DOM event handler.
If you throw inside a React.startTransition callback that's sync, then
that will bubble out of the startTransition but if you throw inside an
async callback or a useTransition we now need to handle it at the hook
site. So in 19 we need to make all React.startTransition swallow the
error (and report them to reportError).
The only one remaining that can throw is flushSync but it doesn't really
make sense for it to throw at the callsite neither because batching.
Just because something rendered in this flush doesn't mean it was
rendered due to what was just scheduled and doesn't mean that it should
abort any of the remaining code afterwards. setState is fire and forget.
It's send an instruction elsewhere, it's not part of the current
imperative code.
Error boundaries never rethrow. Since you should really always have
error boundaries, most of the time, it wouldn't rethrow anyway.
Rethrowing also actually currently drops errors on the floor since we
can only rethrow the first error, so to avoid that we'd need to call
reportError anyway. This happens in RN events.
The other issue with rethrowing is that it logs an extra console.error.
Since we're not sure that user code will actually log it anywhere we
still log it too just like we do with errors inside error boundaries
which leads all of these to log twice.
The goal of this PR is to never rethrow out of React instead, errors
outside of error boundaries get logged to reportError. Event system
errors too.
### Breaking Changes
The main thing this affects is testing where you want to inspect the
errors thrown. To make it easier to port, if you're inside `act` we
track the error into act in an aggregate error and then rethrow it at
the root of `act`. Unlike before though, if you flush synchronously
inside of act it'll still continue until the end of act before
rethrowing.
I expect most user code breakages would be to migrate from `flushSync`
to `act` if you assert on throwing.
However, in the React repo we also have `internalAct` and the
`waitForThrow` helpers. Since these have to use public production
implementations we track these using the global onerror or process
uncaughtException. Unlike regular act, includes both event handler
errors and onRecoverableError by default too. Not just render/commit
errors. So I had to account for that in our tests.
We restore logging an extra log for uncaught errors after the main log
with the component stack in it. We use `console.warn`. This is not yet
ignorable if you preventDefault to the main error event. To avoid
confusion if you don't end up logging the error to console I just added
`An error occurred`.
### Polyfill
All browsers we support really supports `reportError` but not all test
and server environments do, so I implemented a polyfill for browser and
node in `shared/reportGlobalError`. I don't love that this is included
in all builds and gets duplicated into isomorphic even though it's not
actually needed in production. Maybe in the future we can require a
polyfill for this.
### Follow Ups
In a follow up, I'll make caught vs uncaught error handling be
configurable too.
---------
Co-authored-by: Ricky Hanlon <rickhanlonii@gmail.com>
## Summary
We want to enable the new event loop in React Native
(https://github.com/react-native-community/discussions-and-proposals/pull/744)
for all users in the new architecture (determined by the use of
bridgeless, not by the use of Fabric). In order to leverage that, we
need to also set the flag for the React reconciler to use microtasks for
scheduling (so we'll execute them at the right time in the new event
loop).
This migrates from the previous approach using a dynamic flag (to be
used at Meta) with the check of a global set by React Native. The reason
for doing this is:
1) We still need to determine this dynamically in OSS (based on
Bridgeless, not on Fabric).
2) We still need the ability to configure the behavior at Meta, and for
internal build system reasons we cannot access the flag that enables
microtasks in
[`ReactNativeFeatureFlags`](6c28c87c4d/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js (L121)).
## How did you test this change?
Manually synchronized the changes to React Native and ran all tests for
the new architecture on it. Also tested manually.
> [!NOTE]
> This change depends on
https://github.com/facebook/react-native/pull/43397 which has been
merged already
We broke the ability to "break on uncaught exceptions" by adding a
try/catch higher up in the scheduling. We're giving up on fixing that so
we can remove the replay trick inside an event handler.
The issue with that approach is that we end up double logging a lot of
errors in DEV since they get reported to the page.
It's also a lot of complexity around this feature.
This pattern is a petpeeve of mine. I don't consider this best practice
and so most don't have these prefixes. Very inconsistent.
At best this is useless and noisey that you have to parse because the
information is also in the stack trace.
At worse these are misleading because they're highlighting something
internal (like validateDOMNesting) which even suggests an internal bug.
Even the ones public to React aren't necessarily what you called because
you might be calling a wrapper around it.
That would be properly reflected in a stack trace - which can also
properly ignore list so that the first stack you see is your callsite,
Which might be like `render()` in react-testing-library rather than
`createRoot()` for example.
Along with all the places using it like the `_debugSource` on Fiber.
This still lets them be passed into `createElement` (and JSX dev
runtime) since those can still be used in existing already compiled code
and we don't want that to start spreading to DOM attributes.
We used to have a DEV mode that compiles the source location of JSX into
the compiled output. This was nice because we could get the actual call
site of the JSX (instead of just somewhere in the component). It had a
bunch of issues though:
- It only works with JSX.
- The way this source location is compiled is different in all the
pipelines along the way. It relies on this transform being first and the
source location we want to extract but it doesn't get preserved along
source maps and don't have a way to be connected to the source hosted by
the source maps. Ideally it should just use the mechanism other source
maps use.
- Since it's expensive it only works in DEV so if it's used for
component stacks it would vary between dev and prod.
- It only captures the callsite of the JSX and not the stack between the
component and that callsite. In the happy case it's in the component but
not always.
Instead, we have another zero-cost trick to extract the call site of
each component lazily only if it's needed. This ensures that component
stacks are the same in DEV and PROD. At the cost of worse line number
information.
The better way to get the JSX call site would be to get it from `new
Error()` or `console.createTask()` inside the JSX runtime which can
capture the whole stack in a consistent way with other source mappings.
We might explore that in the future.
This removes source location info from React DevTools and React Native
Inspector. The "jump to source code" feature or inspection can be made
lazy instead by invoking the lazy component stack frame generation. That
way it can be made to work in prod too. The filtering based on file path
is a bit trickier.
When redesigned this UI should ideally also account for more than one
stack frame.
With this change the DEV only Babel transforms are effectively
deprecated since they're not necessary for anything.
While inspecting the build artifacts for Fabric in
https://www.internalfb.com/diff/D51816108, I've noticed it has some
leaking implementation details from Paper, such as
`ReactNativeFiberHostComponent`.
The reason for it is the single implementation of
`isChildPublicInstance` in `ReactNativePublicCompat`, in which we were
using `instanceof ReactNativeFiberHostComponent`.
This new implementation removes the `ReactNativeFiberHostComponent`
leak, but decreases the Flow coverage.
Follow-up on https://github.com/facebook/react/pull/27783.
React Native is actually using `ReactNativeTypes`, which are synced from
this repo. In order to make `isChildPublicInstance` visible for
renderers inside React Native repository, we need to list it in
`ReactNativeTypes`.
Because of current circular dependency between React Native and React,
it is impossible to actually type it properly:
- Can't import any types in `ReactNativeTypes` from local files, because
it will break React Native, once synced.
- Implementations can't use real types in their definitions, because it
will break these checks:
223db40d5a/packages/react-native-renderer/fabric.js (L12-L13)223db40d5a/packages/react-native-renderer/index.js (L12-L14)
Adds `isChildPublicInstance` method to both renderers (Fabric and
Paper), which will receive 2 public instances and return if first
argument is an ancestor of the second, based on fibers.
This will be used as a fallback when DOM node APIs are not available:
for Paper renderer or for Fabric without DOM node APIs.
How it is going to be used: to determine which `AppContainer` component
in RN is responsible for highlighting an inspected element on the
screen.
Updates useFormState to allow a sync function to be passed as an action.
A form action is almost always async, because it needs to talk to the
server. But since we support client-side actions, too, there's no reason
we can't allow sync actions, too.
I originally chose not to allow them to keep the implementation simpler
but it's not really that much more complicated because we already
support this for actions passed to startTransition. So now it's
consistent: anywhere an action is accepted, a sync client function is a
valid input.
## Summary
When transpiling `react-native` with `swc` this file caused some trouble
as it mixes ESM and CJS import/export syntax. This PR addresses this by
converting CJS exports to ESM exports. As
`ReactNativeViewConfigRegistry` is synced from `react` to `react-native`
repository, it's required to make the change here. I've also aligned the
mock of `ReactNativeViewConfigRegistry` to reflect current
implementation.
Related PR in `react-native`:
https://github.com/facebook/react-native/pull/40787
## Summary
Currently when cloning nodes in Fabric, we reset a node's children on
each clone, and then repeatedly call appendChild to restore the previous
list of children (even if it was quasi-identical to before). This causes
unnecessary invalidation of the layout state in Fabric's ShadowNode data
(which in turn may require additional yoga clones) and extra JSI calls.
This PR adds a feature flag to pass in the children as part of the clone
call, so Fabric always has a complete view of the node that's being
mutated.
This feature flag requires matching changes in the react-native repo:
https://github.com/facebook/react-native/pull/39817
## How did you test this change?
Unit test added demonstrates the new behaviour
```
yarn test -r www-modern ReactFabric-test
yarn test ReactFabric-test.internal
```
Tested a manual sync into React Native and verified core surfaces render
correctly.
## Summary
This is part of an effort to align the event loop in React Native with
its behavior on the Web. In this case, we're going to test enabling
microtasks in React Native (Fabric) and we need React to schedule work
using microtasks if available there. This just adds a feature flag to
configure that behavior at runtime.
## How did you test this change?
* Reviewed the generated code, which looks ok.
* Did a manual sync of this PR to Meta's internal infra and tested it
with my changes to enable microtasks in RN/Hermes.
## Summary
This is required for the case when we have an instance and want to get
inspector data for it. Such case occurs when RN's application being
debugged via React DevTools.
React DevTools sends instance to RN, which then gets all auxiliary data
to highlight some elements. Having `getInspectorDataForInstance` method
exposed makes it possible to easily get current props from fiber, which
then can be used to display some margins & paddings for hovered element
(via props.style).
I see that `getInspectorDataForInstance` is being exported at the top
level of the renderer, but feels like this should also be inside
DevTools global hook, the same way we use it for
[`getInspectorDataForViewAtPoint`](e7d3662904/packages/react-native/Libraries/Inspector/getInspectorDataForViewAtPoint.js).
The bindings upstream in Relay has been removed so we don't need these
builds anymore. The idea is to revisit an FB integration of Flight but
it wouldn't use the Relay specific bindings. It's a bit unclear how it
would look but likely more like the OSS version so not worth keeping
these around.
The `dom-relay` name also included the FB specific Fizz implementation
of the streaming config so I renamed that to `dom-fb`. There's no Fizz
implementation for Native yet so I just removed `native-relay`.
We created a configurable fork for how to encode the output of Flight
and the Relay implementation encoded it as JSON objects instead of
strings/streams. The new implementation would likely be more stream-like
and just encode it directly as string/binary chunks. So I removed those
indirections so that this can just be declared inline in
ReactFlightServer/Client.
Just a small upgrade to keep us current and remove unused suppressions
(probably fixed by some upgrade since).
- `*` is no longer allowed and has been an alias for `any` for a while
now.
This hook reads the status of its ancestor form component, if it exists.
```js
const {pending, data, action, method} = useFormStatus();
```
It can be used to implement a loading indicator, for example. You can
think of it as a shortcut for implementing a loading state with the
useTransition hook.
For now, it's only available in the experimental channel. We'll share
docs once its closer to being stable. There are additional APIs that
will ship alongside it.
Internally it's implemented using startTransition + a context object.
That's a good way to think about its behavior, but the actual
implementation details may change in the future.
Because form elements cannot be nested, the implementation in the
reconciler does not bother to keep track of multiple nested "transition
providers". So although it's implemented using generic Fiber config
methods, it does currently make some assumptions based on React DOM's
requirements.
Stacked on #26557
Supporting Float methods such as ReactDOM.preload() are challenging for
flight because it does not have an easy means to convey direct
executions in other environments. Because the flight wire format is a
JSON-like serialization that is expected to be rendered it currently
only describes renderable elements. We need a way to convey a function
invocation that gets run in the context of the client environment
whether that is Fizz or Fiber.
Fiber is somewhat straightforward because the HostDispatcher is always
active and we can just have the FlightClient dispatch the serialized
directive.
Fizz is much more challenging becaue the dispatcher is always scoped but
the specific request the dispatch belongs to is not readily available.
Environments that support AsyncLocalStorage (or in the future
AsyncContext) we will use this to be able to resolve directives in Fizz
to the appropriate Request. For other environments directives will be
elided. Right now this is pragmatic and non-breaking because all
directives are opportunistic and non-critical. If this changes in the
future we will need to reconsider how widespread support for async
context tracking is.
For Flight, if AsyncLocalStorage is available Float methods can be
called before and after await points and be expected to work. If
AsyncLocalStorage is not available float methods called in the sync
phase of a component render will be captured but anything after an await
point will be a noop. If a float call is dropped in this manner a DEV
warning should help you realize your code may need to be modified.
This PR also introduces a way for resources (Fizz) and hints (Flight) to
flush even if there is not active task being worked on. This will help
when Float methods are called in between async points within a function
execution but the task is blocked on the entire function finishing.
This PR also introduces deduping of Hints in Flight using the same
resource keys used in Fizz. This will help shrink payload sizes when the
same hint is attempted to emit over and over again
Stacked on #26570
Previously we restricted Float methods to only being callable while
rendering. This allowed us to make associations between calls and their
position in the DOM tree, for instance hoisting preinitialized styles
into a ShadowRoot or an iframe Document.
When considering how we are going to support Flight support in Float
however it became clear that this restriction would lead to compromises
on the implementation because the Flight client does not execute within
the context of a client render. We want to be able to disaptch Float
directives coming from Flight as soon as possible and this requires
being able to call them outside of render.
this patch modifies Float so that its methods are callable anywhere. The
main consequence of this change is Float will always use the Document
the renderer script is running within as the HoistableRoot. This means
if you preinit as style inside a component render targeting a ShadowRoot
the style will load in the ownerDocument not the ShadowRoot. Practially
speaking it means that preinit is not useful inside ShadowRoots and
iframes.
This tradeoff was deemed acceptable because these methods are
optimistic, not critical. Additionally, the other methods, preconntect,
prefetchDNS, and preload, are not impacted because they already operated
at the level of the ownerDocument and really only interface with the
Network cache layer.
I added a couple additional fixes that were necessary for getting tests
to pass that are worth considering separately.
The first commit improves the diff for `waitForThrow` so it compares
strings if possible.
The second commit makes invokeGuardedCallback not use metaprogramming
pattern and swallows any novel errors produced from trying to run the
guarded callback. Swallowing may not be the best we can do but it at
least protects React against rapid failure when something causes the
dispatchEvent to throw.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn debug-test --watch TestName`, open
`chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
## Summary
Browsers restore state like forms and scroll position right after the
popstate event. To make sure the page work as expected on back or
forward button, we need to flush transitions scheduled in a popstate
synchronously, and only yields if it suspends.
This PR adds a new HostConfig method to check if `window.event ===
'popstate'`, and `scheduleMicrotask` if a transition is scheduled in a
`PopStateEvent`.
## How did you test this change?
yarn test
This removes the concept of `prepareUpdate()`, behind a flag.
React Native already does everything in the commit phase, but generates
a temporary update payload before applying it.
React Fabric does it both in the render phase. Now it just moves it to a
single host config.
For DOM I forked updateProperties into one that does diffing and
updating in one pass vs just applying a pre-diffed updatePayload.
There are a few downsides of this approach:
- If only "children" has changed, we end up scheduling an update to be
done in the commit phase. Since we traverse through it anyway, it's
probably not much extra.
- It does more work in the commit phase so for a large tree that is
mostly unchanged, it'll stall longer.
- It does some extra work for special cases since that work happens if
anything has changed. We no longer have a deep bailout.
- The special cases now have to each replicate the "clean up old props"
loop, leading to extra code.
The benefit is that this doesn't allocate temporary extra objects
(possibly multiple per element if the array has to resize). It's less
work overall. It also gives us an option to reuse this function for a
sync render optimization.
Another benefit is that if we do the loop in the commit phase I can do
further optimizations by reading all props that I need for special cases
in that loop instead of polymorphic reads from props. This is what I'd
like to do in future refactors that would be stacked on top of this
change.
part of https://github.com/facebook/react/pull/26571
merging separately to improve tracking of files renames in git
Rename HostConfig files to FiberConfig to clarify they are configs for
Fiber and not Fizz/Flight. This better conforms to the naming used in
Flight and now Fizz of `ReactFlightServerConfig` and `ReactFizzConfig`
## Summary
This adds the ability to create public instances for text nodes in
Fabric. The implementation for the public instances lives in React
Native (as it does for host components after #26437). The logic here
just handles their lazy instantiation when requested via
`getPublicInstanceFromInternalInstanceHandle`, which is called by Fabric
with information coming from the shadow tree.
It's important that the creation of public instances for text nodes is
done lazily to avoid regressing memory usage when unused. Instances for
text nodes are left intact if the public instance is never accessed.
This is necessary to implement access to text nodes in React Native as
explained in
https://github.com/react-native-community/discussions-and-proposals/pull/607
## How did you test this change?
Added unit tests (also fixed a test that was only testing the logic in a
mock :S).
Added an explicit type to all $FlowFixMe suppressions to reduce
over-suppressions of new errors that might be caused on the same lines.
Also removes suppressions that aren't used (e.g. in a `@noflow` file as
they're purely misleading)
Test Plan:
yarn flow-ci
## Summary
Now that React Native owns the definition for public instances in Fabric
and ReactNativePrivateInterface provides the methods to create instances
and access private fields (see
https://github.com/facebook/react-native/pull/36570), we can remove the
definitions from React.
After this PR, React Native public instances will be opaque types for
React and it will only handle their creation but not their definition.
This will make RN similar to DOM in how public instances are handled.
This is a new version of #26418 which was closed without merging.
## How did you test this change?
* Existing tests.
* Manually synced the changes in this PR to React Native and tested it
end to end in Meta's infra.
## Summary
This type was defined as `mixed` to avoid bringing the whole definition
from React to React Native, but its definition is visible to RN. This
type should be opaque to RN, so this makes it explicit.
## How did you test this change?
Applied the same changes in the React Native repository and could use
the type without issues.
When rendering a suspensey resource that we haven't seen before, it may
have loaded in the background while we were rendering. We should yield
to the main thread to see if the load event fires in an immediate task.
For example, if the resource for a link element has already loaded, its
load event will fire in a task right after React yields to the main
thread. Because the continuation task is not scheduled until right
before React yields, the load event will ping React before it resumes.
If this happens, we can resume rendering without showing a fallback.
I don't think this matters much for images, because the `completed`
property tells us whether the image has loaded, and during a non-urgent
render, we never block the main thread for more than 5ms at a time (for
now — we might increase this in the future). It matters more for
stylesheets because the only way to check if it has loaded is by
listening for the load event.
This is essentially the same trick that `use` does for userspace
promises, but a bit simpler because we don't need to replay the host
component's begin phase; the work-in-progress fiber already completed,
so we can just continue onto the next sibling without any additional
work.
As part of this change, I split the `shouldSuspendCommit` host config
method into separate `maySuspendCommit` and `preloadInstance` methods.
Previously `shouldSuspendCommit` was used for both.
This raised a question of whether we should preload resources during a
synchronous render. My initial instinct was that we shouldn't, because
we're going to synchronously block the main thread until the resource is
inserted into the DOM, anyway. But I wonder if the browser is able to
initiate the preload even while the main thread is blocked. It's
probably a micro-optimization either way because most resources will be
loaded during transitions, not urgent renders.
## Summary
We are going to move the definition of public instances from React to
React Native to have them together with the native methods in Fabric
that they invoke. This will allow us to have a better type safety
between them and iterate faster on the implementation of this proposal:
https://github.com/react-native-community/discussions-and-proposals/pull/607
The interface between React and React Native would look like this after
this change and a following PR (#26418):
React → React Native:
```javascript
ReactNativePrivateInterface.createPublicInstance // to provide via refs
ReactNativePrivateInterface.getNodeFromPublicInstance // for DevTools, commands, etc.
ReactNativePrivateInterface.getNativeTagFromPublicInstance // to implement `findNodeHandle`
```
React Native → React (ReactFabric):
```javascript
ReactFabric.getNodeFromInternalInstanceHandle // to get most recent node to call into native
ReactFabric.getPublicInstanceFromInternalInstanceHandle // to get public instances from results from native
```
## How did you test this change?
Flow
Existing unit tests
This adds a new capability for renderers (React DOM, React Native):
prevent a tree from being displayed until it is ready, showing a
fallback if necessary, but without blocking the React components from
being evaluated in the meantime.
A concrete example is CSS loading: React DOM can block a commit from
being applied until the stylesheet has loaded. This allows us to load
the CSS asynchronously, while also preventing a flash of unstyled
content. Images and fonts are some of the other use cases.
You can think of this as "Suspense for the commit phase". Traditional
Suspense, i.e. with `use`, blocking during the render phase: React
cannot proceed with rendering until the data is available. But in the
case of things like stylesheets, you don't need the CSS in order to
evaluate the component. It just needs to be loaded before the tree is
committed. Because React buffers its side effects and mutations, it can
do work in parallel while the stylesheets load in the background.
Like regular Suspense, a "suspensey" stylesheet or image will trigger
the nearest Suspense fallback if it hasn't loaded yet. For now, though,
we only do this for non-urgent updates, like with startTransition. If
you render a suspensey resource during an urgent update, it will revert
to today's behavior. (We may or may not add a way to suspend the commit
during an urgent update in the future.)
In this PR, I have implemented this capability in the reconciler via new
methods added to the host config. I've used our internal React "no-op"
renderer to write tests that demonstrate the feature. I have not yet
implemented Suspensey CSS, images, etc in React DOM. @gnoff and I will
work on that in subsequent PRs.
## Summary
We had to revert the last React sync to React Native because we saw
issues with Responder events using stale event handlers instead of
recent versions.
I reviewed the merged PRs and realized the problem was in the refactor I
did in #26321. In that PR, we moved `currentProps` from `canonical`,
which is a singleton referenced by all versions of the same fiber, to
the fiber itself. This is causing the staleness we observed in events.
This PR does a partial revert of the refactor in #26321, bringing back
the `canonical` object but moving `publicInstance` to one of its fields,
instead of being the `canonical` object itself.
## How did you test this change?
Existing unit tests continue working (I didn't manage to get a repro
using the test renderer).
I manually tested this change in Meta infra and saw the problem was
fixed.
## Summary
I refactored this code in #26290 but forgot to add guards when the fiber
or the state node where null, and this is typed as `any` so Flow didn't
catch it.
This restores the same logic to guard against null.
## How did you test this change?
Existing tests.
I'm trying to get rid of all meta programming in the module scope so
that closure can do a better job figuring out cyclic dependencies and
ability to reorder.
This is converting a lot of the patterns that assign functions
conditionally to using function declarations instead.
```
let fn;
if (__DEV__) {
fn = function() {
...
};
}
```
->
```
function fn() {
if (__DEV__) {
...
}
}
```
## Summary
The current definition of `Instance` in Fabric has 2 fields:
- `node`: reference to the native node in the shadow tree.
- `canonical`: public instance provided to users via refs + some
internal fields needed by Fabric.
We're currently using `canonical` not only as the public instance, but
also to store internal properties that Fabric needs to access in
different parts of the codebase. Those properties are, in fact,
available through refs as well, which breaks encapsulation.
This PR splits that into 2 separate fields, leaving the definition of
instance as:
- `node`: reference to the native node in the shadow tree.
- `publicInstance`: public instance provided to users via refs.
- Rest of internal fields needed by Fabric at the instance level.
This also migrates all the current usages of `canonical` to use the
right property depending on the use case.
To improve encapsulation (and in preparation for the implementation of
this [proposal to bring some DOM APIs to public instances in React
Native](https://github.com/react-native-community/discussions-and-proposals/pull/607)),
this also **moves the creation of and the access to the public instance
to separate modules** (`ReactFabricPublicInstance` and
`ReactFabricPublicInstanceUtils`). In a following diff, that module will
be moved into the `react-native` repository and we'll access it through
`ReactNativePrivateInterface`.
## How did you test this change?
Existing unit tests.
Manually synced the PR in Meta infra and tested in Catalyst + the
integration with DevTools. Everything is working normally.
The www builds include disableLegacyContext as a dynamic flag, so we
should be running the tests in that mode, too. Previously we were
overriding the flag during the test run. This strategy usually doesn't
work because the flags get compiled out in the final build, but we
happen to not test www in build mode, only source.
To get of this hacky override, I added a test gate to every test that
uses legacy context. When we eventually remove legacy context from the
codebase, this should make it slightly easier to find which tests are
affected. And removes one more hack from our hack-ridden test config.
Given that sometimes www has features enabled that aren't on in other
builds, we might want to consider testing its build artifacts in CI,
rather than just source. That would have forced this cleanup to happen
sooner. Currently we only test the public builds in CI.
Prior to #26347, our internal `act` API (not the public API) behaved
differently depending on whether the scope function returned a promise
(i.e. was an async function), for historical reasons that no longer
apply. Now that this is fixed, I've codemodded all async act scopes that
don't contain an await to be sync.
No pressing motivation other than it looks nicer and the codemod was
easy. Might help avoid confusion for new contributors who see async act
scopes with nothing async inside and infer it must be like that for a
reason.
This is not a public API. We only use it for our internal tests, the
ones in this repo. Let's move it to this private package. Practically
speaking this will also let us use async/await in the implementation.
## Summary
In #26283, I changed definition of `NativeMethods` from an object to an
interface. This is correct but introduces a lot of errors in React
Native, so this restores the original definition and exports the fixed
type as a separate type so we can gradually migrate in React Native.
## How did you test this change?
Manually applied this change in React Native and validated the errors
are gone.
Similar to the rationale for `waitFor` (see #26285), we should always
await the result of an `act` call so that microtasks have a chance to
fire.
This only affects the internal `act` that we use in our repo, for now.
In the public `act` API, we don't yet require this; however, we
effectively will for any update that triggers suspense once `use` lands.
So we likely will start warning in an upcoming minor.
