We added this unstable feature a few years ago, as a way to opt out of
context updates, but it didn't prove useful in practice.
We have other proposals for how to address the same problem, like
context selectors.
Since it was prefixed with `unstable_`, we should be able to remove it
without consequence. The hook API already warned if you used it.
Even if someone is using it somewhere, it's meant to be an optimization
only, so if they are using the API properly, it should not have any
semantic impact.
* Remove react/unstable_cache
We're probably going to make it available via the dispatcher. Let's remove this for now.
* Add readContext() to the dispatcher
On the server, it will be per-request.
On the client, there will be some way to shadow it.
For now, I provide it on the server, and throw on the client.
* Use readContext() from react-fetch
This makes it work on the server (but not on the client until we implement it there.)
Updated the test to use Server Components. Now it passes.
* Fixture: Add fetch from a Server Component
* readCache -> getCacheForType<T>
* Add React.unstable_getCacheForType
* Add a feature flag
* Fix Flow
* Add react-suspense-test-utils and port tests
* Remove extra Map lookup
* Unroll async/await because build system
* Add some error coverage and retry
* Add unstable_getCacheForType to Flight entry
* Remove Blocks
* Remove Flight Server Runtime
There's no need for this now that the JSResource is part of the bundler
protocol. Might need something for Webpack plugin specifically later.
* Devtools
And `useDeferredValue`.
The options were already disabled in previous commits, so this doesn't
change any behavior. I upated type signatures and cleaned up the hook
implementation a bit — no longer have to wrap the `start` method with
`useCallback`, because its only remaining dependency is a `setState`
method, which never changes. Instead, we can store the `start` method
on a ref.
Now that the options in SuspenseConfig are no longer supported, the
only thing we use it for is to track whether an update is part of
a transition.
I've renamed `ReactCurrentBatchConfig.suspense` to
`ReactCurrentBatchConfig.transition`, and changed the type to a number.
The number is always either 0 or 1. I could have made it a boolean;
however, most likely this will eventually be either a Lane or an
incrementing identifier.
The `withSuspenseConfig` export still exists until we've removed
all the callers from www.
* Add "unstbale_" prefix to mutable source APIs
* DebugHooks no longer calls useMutableSource() on init
This was causing an observable behavioral difference between experimental DEV and PROD builds.
We don't initialize stack position for other composite hooks (e.g. useDeferredValue, useTransition, useOpaqueIdentifier). If we did, it would cause the same obesrvable behavioral difference.
Some of our internal reconciler types have leaked into other packages.
Usually, these types are treated as opaque; we don't read and write
to its fields. This is good.
However, the type is often passed back to a reconciler method. For
example, React DOM creates a FiberRoot with `createContainer`, then
passes that root to `updateContainer`. It doesn't do anything with the
root except pass it through, but because `updateContainer` expects a
full FiberRoot, React DOM is still coupled to all its fields.
I don't know if there's an idiomatic way to handle this in Flow. Opaque
types are simlar, but those only work within a single file. AFAIK,
there's no way to use a package as the boundary for opaqueness.
The immediate problem this presents is that the reconciler refactor will
involve changes to our internal data structures. I don't want to have to
fork every single package that happens to pass through a Fiber or
FiberRoot, or access any one of its fields. So my current plan is to
share the same Flow type across both forks. The shared type will be a
superset of each implementation's type, e.g. Fiber will have both an
`expirationTime` field and a `lanes` field. The implementations will
diverge, but not the types.
To do this, I lifted the type definitions into a separate module.
* Add useOpaqueIdentifier Hook
We currently use unique IDs in a lot of places. Examples are:
* `<label for="ID">`
* `aria-labelledby`
This can cause some issues:
1. If we server side render and then hydrate, this could cause an
hydration ID mismatch
2. If we server side render one part of the page and client side
render another part of the page, the ID for one part could be
different than the ID for another part even though they are
supposed to be the same
3. If we conditionally render something with an ID , this might also
cause an ID mismatch because the ID will be different on other
parts of the page
This PR creates a new hook `useUniqueId` that generates a different
unique ID based on whether the hook was called on the server or client.
If the hook is called during hydration, it generates an opaque object
that will rerender the hook so that the IDs match.
Co-authored-by: Andrew Clark <git@andrewclark.io>
* Enable prefer-const rule
Stylistically I don't like this but Closure Compiler takes advantage of
this information.
* Auto-fix lints
* Manually fix the remaining callsites
* Revert "ReactDOM.useEvent: enable on internal www and add inspection test (#18395)"
This reverts commit e0ab1a429d.
* Revert "ReactDOM.useEvent: Add support for experimental scopes API (#18375)"
This reverts commit a16b349745.
* ReactDOM.useEvent: Add support for experimental scopes API
* Rename lower case isomorphic default exports modules to upper case named exports
We're somewhat inconsistent here between e.g. ReactLazy and memo.
Let's pick one.
This also moves the responder, fundamental, scope creators from shared
since they're isomorphic and same as the other creators.
* Move some files that are specific to the react-reconciler from shared
Individual renderers are allowed to deep require into the reconciler.
* Move files specific to react-dom from shared
react-interactions is right now dom specific (it wasn't before) so we can
type check it together with other dom stuff. Avoids the need for
a shared ReactDOMTypes to be checked by RN for example.
* Move ReactWorkTags to the reconciler
* Move createPortal to export from reconciler
Otherwise Noop can't access it since it's not allowed deep requires.
useMutableSource hook
useMutableSource() enables React components to safely and efficiently read from a mutable external source in Concurrent Mode. The API will detect mutations that occur during a render to avoid tearing and it will automatically schedule updates when the source is mutated.
RFC: reactjs/rfcs#147
The useState hook has always composed the useReducer hook. 1:1 composition like this is fine.
But some more recent hooks (e.g. useTransition, useDeferredValue) compose multiple hooks internally. This breaks react-debug-tools because it causes off-by-N errors when the debug tools re-renders the function.
For example, if a component were to use the useTransition and useMemo hooks, the normal hooks dispatcher would create a list of first state, then callback, then memo hooks, but the debug tools package would expect a list of transition then memo. This can break user code and cause runtime errors in both the react-debug-tools package and in product code.
This PR fixes the currently broken hooks by updating debug tools to be aware of the composite hooks (how many times it should call nextHook essentially) and adds tests to make sure they don't get out of sync again. We'll need to add similar tests for future composite hooks (like useMutableSource #18000).
* Update Flow to 0.84
* Fix violations
* Use inexact object syntax in files from fbsource
* Fix warning extraction to use a modern parser
* Codemod inexact objects to new syntax
* Tighten types that can be exact
* Revert unintentional formatting changes from codemod
* Add feature flags
* Add Chunk type and constructor
* Wire up Chunk support in the reconciler
* Update reconciler to reconcile Chunks against the render method
This allows the query and args to be updated.
* Drop the ref. Chunks cannot have refs anyway.
* Add Chunk checks in more missing cases
* Rename secondArg
* Add test and fix lazy chunks
Not really a supported use case but for consistency I guess.
* Fix fragment test
* ReactDebugHooks identifies State and Reducer hooks as editable
* Inject overrideHookState() method to DevTools to support editing in DEV builds
* Added an integration test for React DevTools, react-debug-tools, and overrideHookState
* Restrict effect return type to a function or nothing
We already warn in dev if the wrong type is returned. This updates the
Flow type.
* Restrict return type further
* Assume Effect hook returns either a function or undefined
* Tweak warning message
* Improve Reducer Hook's lazy init API
* Use generic type for initilizer input
Still requires an `any` cast in the case where `init` function is
not provided.
* Move DEV-only function right above where it's used
I don't like looking at this top-level function #petty
* Use different dispatchers for functions & classes
Classes support readContext, but not any of the other dispatcher
methods. Function support all methods.
This is a more robust version of our previous strategy of checking
whether `currentlyRenderingFiber` is null.
As a next step, we can use a separate dispatcher for each phase of the
render cycle (mount versus update).
* Use separate dispatchers for mount and update
* Remove mount code from update path
Deletes mount-specific code from the update path, since it should be
unreachable. To continue supporting progressive enhancement (mounting
new hooks at the end of the list), we detect when there are no more
current hooks and switch back to the mount dispatcher. Progressive
enhancement isn't officially supported yet, so it will continue to warn.
* Factoring nits
* Fix Flow
Had to cheat more than I would like
* More Flow nits
* Switch back to using a special dispatcher for nested hooks in DEV
In order for this strategy to work, I had to revert progressive
enhancement support (appending hooks to the end). It was previously a
warning but now it results in an error. We'll reconsider later.
* Always pass args to updateState and updateReducer
Even though the extra args are only used on mount, to ensure
type consistency.
* react-debug-tools accepts currentDispatcher ref as param
* ReactDebugHooks injected dispatcher ref is optional
* Support custom values for custom hooks
* PR feedback:
1. Renamed useDebugValueLabel hook to useDebugValue
2. Wrapped useDebugValue internals in if-DEV so that it could be removed from production builds.
* PR feedback:
1. Fixed some minor typos
2. Added inline comment explaining the purpose of rollupDebugValues()
3. Refactored rollupDebugValues() to use a for loop rather than filter()
4. Improve check for useDebugValue hook to lessen the chance of a false positive
5. Added optional formatter function param to useDebugValue
* Nitpick renamed a method
useMutationEffect has problems (namely, refs aren't attached at the time that it runs) and we're not positive it's necessary. useLayoutEffect runs at the same time as componentDidMount/Update so it's sufficient for all existing use cases; it can be used in any case that useEffect happens too late. Until we figure out what we want to do, let's delete it.
* Add debug tools package
* Add basic implementation
* Implement inspection of the current state of hooks using the fiber tree
* Support useContext hooks inspection by backtracking from the Fiber
I'm not sure this is safe because the return fibers may not be current
but close enough and it's fast.
We use this to set up the current values of the providers.
* rm copypasta
* Use lastIndexOf
Just in case. I don't know of any scenario where this can happen.
* Support ForwardRef
* Add test for memo and custom hooks
* Support defaultProps resolution
