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
In React 19 React will finally stop publishing UMD builds. This is
motivated primarily by the lack of use of UMD format and the added
complexity of maintaining build infra for these releases. Additionally
with ESM becoming more prevalent in browsers and services like esm.sh
which can host React as an ESM module there are other options for doing
script tag based react loading.
This PR removes all the UMD build configs and forks.
There are some fixtures that still have references to UMD builds however
many of them already do not work (for instance they are using legacy
features like ReactDOM.render) and rather than block the removal on
these fixtures being brought up to date we'll just move forward and fix
or removes fixtures as necessary in the future.
We have a different set of dispatchers that Flight uses. This also
includes the `jsx-runtime` which must also be aliased to use the right
version.
To ensure the right versions are used together we rename the export of
the SharedInternals from 'react' and alias it in relevant bundles.
Stacked on #28751
ReactDOMSharedInternals uses properties of considerable length to model
mutuable state. These properties are not mangled during minification and
contribute a not insigificant amount to the uncompressed bundle size and
to a lesser degree compressed bundle size.
This change rewrites the DOMInternals in a way that shortens property
names so we can have smaller builds.
It also treats the entire object as a mutable container rather than
having different mutable sub objects.
The same treatment should be given to ReactSharedInternals
Make it more clear that these flags aren't used in RN OSS.
- Rename
`packages/shared/forks/ReactFeatureFlags.test-renderer.native.js` to
`packages/shared/forks/ReactFeatureFlags.test-renderer.native-fb.js`
- Remove RN OSS build cases consuming the feature flags since there is
no RN OSS RTR build.
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.
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.
The idea here is that host dispatchers are not bound to renders so we
need to be able to dispatch to them at any time. This updates the
implementation to chain these dispatchers so that each renderer can
respond to the dispatch. Semantically we don't always want every
renderer to do this for instance if Fizz handles a float method we don't
want Fiber to as well so each dispatcher implementation can decide if it
makes sense to forward the call or not. For float methods server
disaptchers will handle the call if they can resolve a Request otherwise
they will forward. For client dispatchers they will handle the call and
always forward. The choice needs to be made for each dispatcher method
and may have implications on correct renderer import order. For now we
just live with the restriction that if you want to use server and client
together (such as renderToString in the browser) you need to import the
server renderer after the client renderer.
The internal file ReactSharedSubset is what the `react` module resolves
to when imported from a Server Component environment. We gave it this
name because, originally, the idea was that Server Components can access
a subset of the APIs available on the client.
However, since then, we've also added APIs that can _only_ by accessed
on the server and not the client. In other words, it's no longer a
subset, it's a slightly different overlapping set.
So this commit renames ReactSharedSubet to ReactServer and updates all
the references. This does not affect the public API, only our internal
implementation.
## Summary
Follow up from #27717 based on feedback to rename the fork module itself
## How did you test this change?
- `yarn build`
- `yarn test
packages/scheduler/src/__tests__/SchedulerUMDBundle-test.internal.js`
Co-authored-by: Jack Pope <jackpope@meta.com>
This PR adds a new FB-specific configuration of Flight. We also need to
bundle a version of ReactSharedSubset that will be used for running
Flight on the server.
This initial implementation does not support server actions yet.
The FB-Flight still uses the text protocol on the server (the flag
`enableBinaryFlight` is set to false). It looks like we need some
changes in Hermes to properly support this binary format.
## Summary
After changes in https://github.com/facebook/react/pull/27436, UMD
builds no longer expose Scheduler from ReactSharedInternals. This module
is forked in rollup for UMD builds and the path no longer matches. This
PR updates the path name to match the new module:
ReactSharedInternalsClient.
## How did you test this change?
- `yarn build`
- Inspect `react.development.js` UMD build, observe `Scheduler:
Scheduler` is set in `ReactSharedInternals`, matching
[18.2.0](https://unpkg.com/react@18.2.0/umd/react.development.js)
- ran attribute-behavior fixture app
- Observe no more error `Uncaught (in promise) TypeError: Cannot read
properties of undefined (reading 'unstable_cancelCallback')`
Co-authored-by: Jack Pope <jackpope@meta.com>
I do this by simply renaming the secret export name in the "subset"
bundle and this renamed version is what the FlightServer uses.
This requires us to be more diligent about always using the correct
instance of "react" in our tests so there's a bunch of clean up for
that.
Adds a separate entry point for the react-dom package when it's accessed
from a Server Component environment, using the "react-server" export
condition.
When you're inside a Server Component module, you won't be able to
import client-only APIs like useState. This applies to almost all React
DOM exports, except for Float ones like preload.
Search for more generic fork files if an exact match does not exist. If
`forks/MyFile.dom.js` exists but `forks/MyFile.dom-node.js` does not
then use it when trying to resolve forks for the `"dom-node"` renderer
in flow, tests, and build
consolidate certain fork files that were identical and make semantic
sense to be generalized
add `dom-browser-esm` bundle and use it for
`react-server-dom-esm/client.browser` build
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`
This doesn't need its own set of flags. We use things like `__PROFILE__`
in the regular feature flags file to fork for the `react-dom/profiling`
build so we can do the same here if needed but I don't think we actually
need to fork this anywhere as far as I can tell.
This isn't the right way to do this, but internally we have some
restrictions so we need to add an indirection. Let's land this now so we
can catch up our sync and then fix forward from there.
Co-authored-by: Jan Kassens <jkassens@meta.com>
We've heard from multiple contributors that the Reconciler forking
mechanism was confusing and/or annoying to deal with. Since it's
currently unused and there's no immediate plans to start using it again,
this removes the forking.
Fully removing the fork is split into 2 steps to preserve file history:
**This PR**
- remove `enableNewReconciler` feature flag.
- remove `unstable_isNewReconciler` export
- remove eslint rules for cross fork imports
- remove `*.new.js` files and update imports
- merge non-suffixed files into `*.old` files where both exist
(sometimes types were defined there)
**#25775**
- rename `*.old` files
* Missing Hooks
* Remove www forks. These can use __SECRET... instead.
* Move cache to separate dispatcher
These will be available in more contexts than just render.
Publish an aliasable entry for `react-dom` top level package exports for use in server environments. This is a stub containing only the exports that we expect to retain in the top level once 19 is released
* Remove object-assign polyfill
We really rely on a more modern environment where this is typically
polyfilled anyway and we don't officially support IE with more extensive
polyfilling anyway. So all environments should have the native version
by now.
* Use shared/assign instead of Object.assign in code
This is so that we have one cached local instance in the bundle.
Ideally we should have a compile do this for us but we already follow
this pattern with hasOwnProperty, isArray, Object.is etc.
* Transform Object.assign to now use shared/assign
We need this to use the shared instance when Object.spread is used.
The unstable-shared-subset.js file is not a public module — it's a
private module that the "react" package maps to when it's accessed from
the "react-server" package.
We originally added it because it was required to make our Rollup
configuration work, because at the time only "public" modules could act
as the entry point for a build artifact — that's why it's prefixed with
"unstable". We've since updated our Rollup config to support private
entry points, so we can remove the extra indirection.
Alternative to #23254
Our build script has a custom plugin to resolve internal module forks.
Currently, it uses require.resolve to resolve the path to a real file
on disk.
Instead, I've updated all the forked module paths to match their
location on disk, relative to the project root, to remove the need to
resolve them in the build script's runtime.
The main motivation is because require.resolve doesn't work with ESM
modules, but aside from that, hardcoding the relative paths is more
predictable — the Node module resolution algorithm is complicated, and
we don't really need its features for this purpose.
* Use consistent naming for unstable_testing entry point
* Exclude the testing build from non-experimental builds except at FB
* FB builds shouldn't contribute to whether we include the npm files
* Exclude exports fields if we delete the files entry
* Move test to no longer be internal so we can test against the build
* Update the bundle artifact names since they've now changed
* Gate import since it doesn't exist
* Move useSyncExternalStore shim to a nested entrypoint
Also renames `useSyncExternalStoreExtra` to
`useSyncExternalStoreWithSelector`.
- 'use-sync-external-store/shim' -> A shim for `useSyncExternalStore`
that works in React 16 and 17 (any release that supports hooks). The
module will first check if the built-in React API exists, before
falling back to the shim.
- 'use-sync-external-store/with-selector' -> An extended version of
`useSyncExternalStore` that also supports `selector` and `isEqual`
options. It does _not_ shim `use-sync-external-store`; it composes the
built-in React API. **Use this if you only support 18+.**
- 'use-sync-external-store/shim/with-selector' -> Same API, but it
composes `use-sync-external-store/shim` instead. **Use this for
compatibility with 16 and 17.**
- 'use-sync-external-store' -> Re-exports React's built-in API. Not
meant to be used. It will warn and direct users to either the shim or
the built-in API.
* Upgrade useSyncExternalStore to alpha channel
The event priority constants exports by the reconciler package are
meant to be used by the reconciler (host config) itself. So it doesn't
make sense to export them from a module that requires them.
To break the cycle, we can move them to a separate module and import
that. This looks like a "deep import" of an internal module, which we
try to avoid, but conceptually these are part of the public interface
of the reconciler module. So, no different than importing from the main
`react-reconciler`.
We do need to be careful about not mixing these types of imports with
implementation details. Those are the ones to really avoid.
An unintended benefit of the reconciler fork infra is that it makes
deep imports harder. Any module that we treat as "public", like this
one, needs to account for the `enableNewReconciler` flag and forward
to the correct implementation.
This configures the Flight fixture to use the "react-server" environment.
This allows the package.json exports field to specify a different resolution
in this environment.
I use this in the "react" package to resolve to a new bundle that excludes
the Hooks that aren't relevant in this environment like useState and useEffect.
This allows us to error early if these names are imported. If we actually
published ESM, it would we a static error. Now it's a runtime error.
You can test this by importing useState in Container.js which is used
by the client and server.
This updates the experimental Scheduler postTask build to call postTask
directly, instead of managing our own custom queue and work loop.
We still use a deadline 5ms mechanism to implement `shouldYield`.
The main thing that postTask is currently missing is the continuation
feature — when yielding to the main thread, the yielding task is sent
to the back of the queue, instead of maintaining its position.
While this would be nice to have, even without it, postTask may be good
enough to replace our userspace implementation.
We'll run some tests to see.
* Move unsubscribe fork to EventListener
That way we can statically compile out more of these indirections.
* Don't use the EventListener fork for Modern WWW builds
This PR adds the jsx-runtime and jsx-dev-runtime modules for the JSX Babel Plugin. WWW still relies on jsx/jsxs/jsxDEV from the "react" module, so once we refactor the code to point to the runtime modules we will remove jsx/jsxs/jsxDEV from the "react" module.
