* [Fizz/Float] Float for stylesheet resources
This commit implements Float in Fizz and on the Client. The initial set of supported APIs is roughly
1. Convert certain stylesheets into style Resources when opting in with precedence prop
2. Emit preloads for stylesheets and explicit preload tags
3. Dedupe all Resources by href
4. Implement ReactDOM.preload() to allow for imperative preloading
5. Implement ReactDOM.preinit() to allow for imperative preinitialization
Currently supports
1. style Resources (link rel "stylesheet")
2. font Resources (preload as "font")
later updates will include support for scripts and modules
* [Flight] Move from suspensey readRoot() to use(thenable)
* Update noop tests
These are no longer sync so they need some more significant updating.
Some of these tests are written in a non-idiomatic form too which is not
great.
* Update Relay tests
I kept these as sync for now and just assume a sync Promise.
* Updated the main tests
* Gate tests
* We need to cast through any because Thenable doesn't support unknown strings
add more accurate end time for transitions and update host configs with `requestPostPaintCallback` function and move post paint logic to another module and use it in the work loop
Implement basic support for "Resources". In the context of this commit, the only thing that is currently a Resource are
<link rel="stylesheet" precedence="some-value" ...>
Resources can be rendered anywhere in the react tree, even outside of normal parenting rules, for instance you can render a resource before you have rendered the <html><head> tags for your application. In the stream we reorder this so the browser always receives valid HTML and resources are emitted either in place (normal circumstances) or at the top of the <head> (when you render them above or before the <head> in your react tree)
On the client, resources opt into an entirely different hydration path. Instead of matching the location within the Document these resources are queried for in the entire document. It is an error to have more than one resource with the same href attribute.
The use of precedence here as an opt-in signal for resourcifying the link is in preparation for a more complete Resource implementation which will dedupe resource references (multiple will be valid), hoist to the appropriate container (body, head, or elsewhere), order (according to precedence) and Suspend boundaries that depend on them. More details will come in the coming weeks on this plan.
This feature is gated by an experimental flag and will only be made available in experimental builds until some future time.
We only really use this for the create APIs since the DOM requires it.
We could probably use the Host Context for this instead since they're
updated at the same time and the namespace is related to this concept.
* Always push updates to interleaved queue first
Interleaves updates (updates that are scheduled while another render
is already is progress) go into a special queue that isn't applied until
the end of the current render. They are transferred to the "real" queue
at the beginning of the next render.
Currently we check during `setState` whether an update should go
directly onto the real queue or onto the special interleaved queue. The
logic is subtle and it can lead to bugs if you mess it up, as in #24400.
Instead, this changes it to always go onto the interleaved queue. The
behavior is the same but the logic is simpler.
As a further step, we can also wait to update the `childLanes` until
the end of the current render. I'll do this in the next step.
* Move setState return path traversal to own call
A lot of the logic around scheduling an update needs access to the
fiber root. To obtain this reference, we must walk up the fiber return
path. We also do this to update `childLanes` on all the parent
nodes, so we can use the same traversal for both purposes.
The traversal currently happens inside `scheduleUpdateOnFiber`, but
sometimes we need to access it beyond that function, too.
So I've hoisted the traversal out of `scheduleUpdateOnFiber` into its
own function call that happens at the beginning of the
`setState` algorithm.
* Rename ReactInterleavedUpdates -> ReactFiberConcurrentUpdates
The scope of this module is expanding so I've renamed accordingly. No
behavioral changes.
* Enqueue and update childLanes in same function
During a setState, the childLanes are updated immediately, even if a
render is already in progress. This can lead to subtle concurrency bugs,
so the plan is to wait until the in-progress render has finished before
updating the childLanes, to prevent subtle concurrency bugs.
As a step toward that change, when scheduling an update, we should not
update the childLanes directly, but instead defer to the
ReactConcurrentUpdates module to do it at the appropriate time.
This makes markUpdateLaneFromFiberToRoot a private function that is
only called from the ReactConcurrentUpdates module.
* [FORKED] Don't update childLanes until after current render
(This is the riskiest commit in the stack. Only affects the "new"
reconciler fork.)
Updates that occur in a concurrent event while a render is already in
progress can't be processed during that render. This is tricky to get
right. Previously we solved this by adding concurrent updates to a
special `interleaved` queue, then transferring the `interleaved` queue
to the `pending` queue after the render phase had completed.
However, we would still mutate the `childLanes` along the parent path
immediately, which can lead to its own subtle data races.
Instead, we can queue the entire operation until after the render phase
has completed. This replaces the need for an `interleaved` field on
every fiber/hook queue.
The main motivation for this change, aside from simplifying the logic a
bit, is so we can read information about the current fiber while we're
walking up its return path, like whether it's inside a hidden tree.
(I haven't done anything like that in this commit, though.)
* Add 17691ac to forked revisions
* Implements useId hook for Flight server.
The approach for ids for Flight is different from Fizz/Client where there is a need for determinancy. Flight rendered elements will not be rendered on the client and as such the ids generated in a request only need to be unique. However since FLight does support refetching subtrees it is possible a client will need to patch up a part of the tree rather than replacing the entire thing so it is not safe to use a simple incrementing counter. To solve for this we allow the caller to specify a prefix. On an initial fetch it is likely this will be empty but on refetches or subtrees we expect to have a client `useId` provide the prefix since it will guaranteed be unique for that subtree and thus for the entire tree. It is also possible that we will automatically provide prefixes based on a client/Fizz useId on refetches
in addition to the core change I also modified the structure of options for renderToReadableStream where `onError`, `context`, and the new `identifierPrefix` are properties of an Options object argument to avoid the clumsiness of a growing list of optional function arguments.
* defend against useId call outside of rendering
* switch to S from F for Server Component ids
* default to empty string identifier prefix
* Add a test demonstrating that there is no warning when double rendering on the client a server component that used useId
* lints and gates
* use return from onError
* export getSuspenseInstanceFallbackError
* stringToChunk
* return string from onError in downstream type signatures
* 1 more type
* support encoding errors in html stream and escape user input
This commit adds another way to get errors to the suspense instance by encoding them as dataset properties of a template element at the head of the boundary. Previously if there was an error before the boundary flushed there was no way to stream the error to the client because there would never be a client render instruction.
Additionally the error is sent in 3 parts
1) error hash - this is always sent (dev or prod) if one is provided
2) error message - Dev only
3) error component stack - Dev only, this now captures the stack at the point of error
Another item addressed in this commit is the escaping of potentially unsafe data. all error components are escaped as test for browers when written into the html and as javascript strings when written into a client render instruction.
* nits
Co-authored-by: Marco Salazar <salazarm@fb.com>
* [Fizz] Improve text separator byte efficiency
Previously text separators were inserted following any Text node in Fizz. This increases bytes sent when streaming and in some cases such as title elements these separators are not interpreted as comment nodes and leak into the visual aspects of a page as escaped text.
The reason simple tracking on the last pushed type doesn't work is that Segments can be filled in asynchronously later and so you cannot know in a single pass whether the preceding content was a text node or not. This commit adds a concept of TextEmbedding which provides a best effort signal to Segments on whether they are embedded within text. This allows the later resolution of that Segment to add text separators when possibly necessary but avoid them when they are surely not.
The current implementation can only "peek" head if the segment is a the Root Segment or a Suspense Boundary Segment. In these cases we know there is no trailing text embedding and we can eliminate the separator at the end of the segment if the last emitted element was Text. In normal Segments we cannot peek and thus have to assume there might be a trailing text embedding and we issue a separator defensively. This should be rare in practice as it is assumed most components that will cause segment creation will also emit some markup at the edges.
* [Fizz] Improve separator efficiency when flushing delayed segments
The method by which we get segment markup into the DOM differs depending on when the Segment resolves.
If a Segment resolves before flushing begins for it's parent it will be emitted inline with the parent markup. In these cases separators may be necessary because they are how we clue the browser into breakup up text into distinct nodes that will later match up with what will be hydrated on the client.
If a Segment resolves after flushing has happened a script will be used to patch up the DOM in the client. when this happens if there are any text nodes on the boundary of the patch they won't be "merged" and thus will continue to have distinct representation as Nodes in the DOM. Thus we can avoid doing any separators at the boundaries in these cases.
After applying these changes the only time you will get text separators as follows
* in between serial text nodes that emit at the same time - these are necessary and cannot be eliminated unless we stop relying on the browser to automatically parse the correct text nodes when processing this HTML
* after a final text node in a non-boundary segment that resolves before it's parent has flushed - these are sometimes extraneous, like when the next emitted thing is a non-Text node.
In all other cases text separators should be omitted which means the general byte efficiency of this approach should be pretty good
On the server we have a similar translation map from the file path that the
loader uses to the refer to the original module and to the bundled module ID.
The Flight server is optimized to emit the smallest format for the client.
However during SSR, the same client component might go by a different
module ID since it's a different bundle than the client bundle.
This provides an option to add a translation map from client ID to SSR ID
when reading the Flight stream.
Ideally we should have a special SSR Flight Client that takes this option
but for now we only have one Client for both.
* Pass children to hydration root constructor
I already made this change for the concurrent root API in #23309. This
does the same thing for the legacy API.
Doesn't change any behavior, but I will use this in the next steps.
* Add isRootDehydrated function
Currently this does nothing except read a boolean field, but I'm about
to change this logic.
Since this is accessed by React DOM, too, I put the function in a
separate module that can be deep imported. Previously, it was accessing
the FiberRoot directly. The reason it's a separate module is to break a
circular dependency between React DOM and the reconciler.
* Allow updates at lower pri without forcing client render
Currently, if a root is updated before the shell has finished hydrating
(for example, due to a top-level navigation), we immediately revert to
client rendering. This is rare because the root is expected is finish
quickly, but not exceedingly rare because the root may be suspended.
This adds support for updating the root without forcing a client render
as long as the update has lower priority than the initial hydration,
i.e. if the update is wrapped in startTransition.
To implement this, I had to do some refactoring. The main idea here is
to make it closer to how we implement hydration in Suspense boundaries:
- I moved isDehydrated from the shared FiberRoot object to the
HostRoot's state object.
- In the begin phase, I check if the root has received an by comparing
the new children to the initial children. If they are different, we
revert to client rendering, and set isDehydrated to false using a
derived state update (a la getDerivedStateFromProps).
- There are a few places where we used to set root.isDehydrated to false
as a way to force a client render. Instead, I set the ForceClientRender
flag on the root work-in-progress fiber.
- Whenever we fall back to client rendering, I log a recoverable error.
The overall code structure is almost identical to the corresponding
logic for Suspense components.
The reason this works is because if the update has lower priority than
the initial hydration, it won't be processed during the hydration
render, so the children will be the same.
We can go even further and allow updates at _higher_ priority (though
not sync) by implementing selective hydration at the root, like we do
for Suspense boundaries: interrupt the current render, attempt hydration
at slightly higher priority than the update, then continue rendering the
update. I haven't implemented this yet, but I've structured the code in
anticipation of adding this later.
* Wrap useMutableSource logic in feature flag
I already made this change for the concurrent root API in #23309. This
does the same thing for the legacy API.
Doesn't change any behavior, but I will use this in the next steps.
* Flight side of server context
* 1 more test
* rm unused function
* flow+prettier
* flow again =)
* duplicate ReactServerContext across packages
* store default value when lazily initializing server context
* .
* better comment
* derp... missing import
* rm optional chaining
* missed feature flag
* React.__SECRET_INTERNALS_DO_NOT_USE_OR_YOU_WILL_BE_FIRED ??
* add warning if non ServerContext passed into useServerContext
* pass context in as array of arrays
* make importServerContext nott pollute the global context state
* merge main
* remove useServerContext
* dont rely on object getters in ReactServerContext and disallow JSX
* add symbols to devtools + rename globalServerContextRegistry to just ContextRegistry
* gate test case as experimental
* feedback
* remove unions
* Lint
* fix oopsies (tests/lint/mismatching arguments/signatures
* lint again
* replace-fork
* remove extraneous change
* rebase
* 1 more test
* rm unused function
* flow+prettier
* flow again =)
* duplicate ReactServerContext across packages
* store default value when lazily initializing server context
* .
* better comment
* derp... missing import
* rm optional chaining
* missed feature flag
* React.__SECRET_INTERNALS_DO_NOT_USE_OR_YOU_WILL_BE_FIRED ??
* add warning if non ServerContext passed into useServerContext
* pass context in as array of arrays
* make importServerContext nott pollute the global context state
* merge main
* remove useServerContext
* dont rely on object getters in ReactServerContext and disallow JSX
* add symbols to devtools + rename globalServerContextRegistry to just ContextRegistry
* gate test case as experimental
* feedback
* remove unions
* Lint
* fix oopsies (tests/lint/mismatching arguments/signatures
* lint again
* replace-fork
* remove extraneous change
* rebase
* reinline
* rebase
* add back changes lost due to rebase being hard
* emit chunk for provider
* remove case for React provider type
* update type for SomeChunk
* enable flag with experimental
* add missing types
* fix flow type
* missing type
* t: any
* revert extraneous type change
* better type
* better type
* feedback
* change import to type import
* test?
* test?
* remove react-dom
* remove react-native-renderer from react-server-native-relay/package.json
* gate change in FiberNewContext, getComponentNameFromType, use switch statement in FlightServer
* getComponentNameFromTpe: server context type gated and use displayName if available
* fallthrough
* lint....
* POP
* lint
* I forgot to call onFatalError
I can't figure out how to write a test for this because it only happens
when there is a bug in React itself which would then be fixed if we found
it.
We're also covered by the protection of ReadableStream which doesn't leak
other errors to us.
* Abort requests if the reader cancels
No need to continue computing at this point.
* Abort requests if node streams get destroyed
This is if the downstream cancels is for example.
* Rename Node APIs for Parity with allReady
The "Complete" terminology is a little misleading because not everything
has been written yet. It's just "Ready" to be written now.
onShellReady
onShellError
onAllReady
* 'close' should be enough
* 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.
This function was modeled after Node streams where write returns a boolean
whether to keep writing or not. I think we should probably switch this
up and read desired size explicitly in appropriate places.
However, in the meantime, we don't have to return a value where we're
not going to use it. So I split this so that we call writeChunkAndReturn
if we're going to return the boolean.
This should help with the compilation so that they can be inlined.
- Add the type of transition tracing callbacks
- Add transition tracing callbacks as an option to `createRoot`
- Add transition tracing callbacks on the root
- Add option to pass transition tracing callbacks to createReactNoop
Minor follow up to initial onRecoverableError PR.
When onRecoverableError is not provided to `createRoot`, the
renderer falls back to a default implementation. Originally I
implemented this with a host config method, but what we can do instead
is pass the default implementation the root constructor as if it were
a user provided one.
* Add .browser and .node explicit entry points
This can be useful when the automatic selection doesn't work properly.
* Remove react/index
I'm not sure why I added this in the first place. Perhaps due to how our
builds work somehow.
* Remove build-info.json from files field
* [RFC] Add onHydrationError option to hydrateRoot
This is not the final API but I'm pushing it for discussion purposes.
When an error is thrown during hydration, we fallback to client
rendering, without triggering an error boundary. This is good because,
in many cases, the UI will recover and the user won't even notice that
something has gone wrong behind the scenes.
However, we shouldn't recover from these errors silently, because the
underlying cause might be pretty serious. Server-client mismatches are
not supposed to happen, even if UI doesn't break from the users
perspective. Ignoring them could lead to worse problems later. De-opting
from server to client rendering could also be a significant performance
regression, depending on the scope of the UI it affects.
So we need a way to log when hydration errors occur.
This adds a new option for `hydrateRoot` called `onHydrationError`. It's
symmetrical to the server renderer's `onError` option, and serves the
same purpose.
When no option is provided, the default behavior is to schedule a
browser task and rethrow the error. This will trigger the normal browser
behavior for errors, including dispatching an error event. If the app
already has error monitoring, this likely will just work as expected
without additional configuration.
However, we can also expose additional metadata about these errors, like
which Suspense boundaries were affected by the de-opt to client
rendering. (I have not exposed any metadata in this commit; API needs
more design work.)
There are other situations besides hydration where we recover from an
error without surfacing it to the user, or notifying an error boundary.
For example, if an error occurs during a concurrent render, it could be
due to a data race, so we try again synchronously in case that fixes it.
We should probably expose a way to log these types of errors, too. (Also
not implemented in this commit.)
* Log all recoverable errors
This expands the scope of onHydrationError to include all errors that
are not surfaced to the UI (an error boundary). In addition to errors
that occur during hydration, this also includes errors that recoverable
by de-opting to synchronous rendering. Typically (or really, by
definition) these errors are the result of a concurrent data race;
blocking the main thread fixes them by prevents subsequent races.
The logic for de-opting to synchronous rendering already existed. The
only thing that has changed is that we now log the errors instead of
silently proceeding.
The logging API has been renamed from onHydrationError
to onRecoverableError.
* Don't log recoverable errors until commit phase
If the render is interrupted and restarts, we don't want to log the
errors multiple times.
This change only affects errors that are recovered by de-opting to
synchronous rendering; we'll have to do something else for errors
during hydration, since they use a different recovery path.
* Only log hydration error if client render succeeds
Similar to previous step.
When an error occurs during hydration, we only want to log it if falling
back to client rendering _succeeds_. If client rendering fails,
the error will get reported to the nearest error boundary, so there's
no need for a duplicate log.
To implement this, I added a list of errors to the hydration context.
If the Suspense boundary successfully completes, they are added to
the main recoverable errors queue (the one I added in the
previous step.)
* Log error with queueMicrotask instead of Scheduler
If onRecoverableError is not provided, we default to rethrowing the
error in a separate task. Originally, I scheduled the task with
idle priority, but @sebmarkbage made the good point that if there are
multiple errors logs, we want to preserve the original order. So I've
switched it to a microtask. The priority can be lowered in userspace
by scheduling an additional task inside onRecoverableError.
* Only use host config method for default behavior
Redefines the contract of the host config's logRecoverableError method
to be a default implementation for onRecoverableError if a user-provided
one is not provided when the root is created.
* Log with reportError instead of rethrowing
In modern browsers, reportError will dispatch an error event, emulating
an uncaught JavaScript error. We can do this instead of rethrowing
recoverable errors in a microtask, which is nice because it avoids any
subtle ordering issues.
In older browsers and test environments, we'll fall back
to console.error.
* Naming nits
queueRecoverableHydrationErrors -> upgradeHydrationErrorsToRecoverable
When an `identifierPrefix` option is given, React will add it to the
beginning of ids generated by `useId`.
The main use case is to avoid conflicts when there are multiple React
roots on a single page.
The server API already supported an `identifierPrefix` option. It's not
only used by `useId`, but also for React-generated ids that are used to
stitch together chunks of HTML, among other things. I added a
corresponding option to the client.
You must pass the same prefix option to both the server and client.
Eventually we may make this automatic by sending the prefix from the
server as part of the HTML stream.
* Add option to inject bootstrap scripts
These are emitted right after the shell as flushed.
* Update ssr fixtures to use bootstrapScripts instead of manual script tag
* Add option to FB renderer too
* Pass in Destination lazily in startFlowing instead of createRequest
* Delay fatal errors until we have a destination to forward them to
* Flow can now be inferred by whether there's a destination set
We can drop the destination when we're not flowing since there's nothing to
write to.
Fatal errors now close once flowing starts back up again.
* Defer fatal errors in Flight too
* Remove reentrant check from Fizz/Flight
* Make startFlowing explicit in Flight
This is already an explicit call in Fizz. This moves flowing to be explicit.
That way we can avoid calling it in start() for web streams and therefore
avoid the reentrant call.
* Add regression test
This test doesn't actually error due to the streams polyfill not behaving
like Chrome but rather according to spec.
* Update the Web Streams polyfill
Not that we need this but just in case there are differences that are fixed.
* Move flushSync warning to React DOM
When you call in `flushSync` from an effect, React fires a warning. I've
moved the implementation of this warning out of the reconciler and into
React DOM.
`flushSync` is a renderer API, not an isomorphic API, because it has
behavior that was designed specifically for the constraints of React
DOM. The equivalent API in a different renderer may not be the same.
For example, React Native has a different threading model than the
browser, so it might not make sense to expose a `flushSync` API to the
JavaScript thread.
* Make root.unmount() synchronous
When you unmount a root, the internal state that React stores on the
DOM node is immediately cleared. So, we should also synchronously
delete the React tree. You should be able to create a new root using
the same container.
* Revise ESLint rules for string coercion
Currently, react uses `'' + value` to coerce mixed values to strings.
This code will throw for Temporal objects or symbols.
To make string-coercion safer and to improve user-facing error messages,
This commit adds a new ESLint rule called `safe-string-coercion`.
This rule has two modes: a production mode and a non-production mode.
* If the `isProductionUserAppCode` option is true, then `'' + value`
coercions are allowed (because they're faster, although they may
throw) and `String(value)` coercions are disallowed. Exception:
when building error messages or running DEV-only code in prod
files, `String()` should be used because it won't throw.
* If the `isProductionUserAppCode` option is false, then `'' + value`
coercions are disallowed (because they may throw, and in non-prod
code it's not worth the risk) and `String(value)` are allowed.
Production mode is used for all files which will be bundled with
developers' userland apps. Non-prod mode is used for all other React
code: tests, DEV blocks, devtools extension, etc.
In production mode, in addiiton to flagging `String(value)` calls,
the rule will also flag `'' + value` or `value + ''` coercions that may
throw. The rule is smart enough to silence itself in the following
"will never throw" cases:
* When the coercion is wrapped in a `typeof` test that restricts to safe
(non-symbol, non-object) types. Example:
if (typeof value === 'string' || typeof value === 'number') {
thisWontReport('' + value);
}
* When what's being coerced is a unary function result, because unary
functions never return an object or a symbol.
* When the coerced value is a commonly-used numeric identifier:
`i`, `idx`, or `lineNumber`.
* When the statement immeidately before the coercion is a DEV-only
call to a function from shared/CheckStringCoercion.js. This call is a
no-op in production, but in DEV it will show a console error
explaining the problem, then will throw right after a long explanatory
code comment so that debugger users will have an idea what's going on.
The check function call must be in the following format:
if (__DEV__) {
checkXxxxxStringCoercion(value);
};
Manually disabling the rule is usually not necessary because almost all
prod use of the `'' + value` pattern falls into one of the categories
above. But in the rare cases where the rule isn't smart enough to detect
safe usage (e.g. when a coercion is inside a nested ternary operator),
manually disabling the rule will be needed.
The rule should also be manually disabled in prod error handling code
where `String(value)` should be used for coercions, because it'd be
bad to throw while building an error message or stack trace!
The prod and non-prod modes have differentiated error messages to
explain how to do a proper coercion in that mode.
If a production check call is needed but is missing or incorrect
(e.g. not in a DEV block or not immediately before the coercion), then
a context-sensitive error message will be reported so that developers
can figure out what's wrong and how to fix the problem.
Because string coercions are now handled by the `safe-string-coercion`
rule, the `no-primitive-constructor` rule no longer flags `String()`
usage. It still flags `new String(value)` because that usage is almost
always a bug.
* Add DEV-only string coercion check functions
This commit adds DEV-only functions to check whether coercing
values to strings using the `'' + value` pattern will throw. If it will
throw, these functions will:
1. Display a console error with a friendly error message describing
the problem and the developer can fix it.
2. Perform the coercion, which will throw. Right before the line where
the throwing happens, there's a long code comment that will help
debugger users (or others looking at the exception call stack) figure
out what happened and how to fix the problem.
One of these check functions should be called before all string coercion
of user-provided values, except when the the coercion is guaranteed not
to throw, e.g.
* if inside a typeof check like `if (typeof value === 'string')`
* if coercing the result of a unary function like `+value` or `value++`
* if coercing a variable named in a whitelist of numeric identifiers:
`i`, `idx`, or `lineNumber`.
The new `safe-string-coercion` internal ESLint rule enforces that
these check functions are called when they are required.
Only use these check functions in production code that will be bundled
with user apps. For non-prod code (and for production error-handling
code), use `String(value)` instead which may be a little slower but will
never throw.
* Add failing tests for string coercion
Added failing tests to verify:
* That input, select, and textarea elements with value and defaultValue
set to Temporal-like objects which will throw when coerced to string
using the `'' + value` pattern.
* That text elements will throw for Temporal-like objects
* That dangerouslySetInnerHTML will *not* throw for Temporal-like
objects because this value is not cast to a string before passing to
the DOM.
* That keys that are Temporal-like objects will throw
All tests above validate the friendly error messages thrown.
* Use `String(value)` for coercion in non-prod files
This commit switches non-production code from `'' + value` (which
throws for Temporal objects and symbols) to instead use `String(value)`
which won't throw for these or other future plus-phobic types.
"Non-produciton code" includes anything not bundled into user apps:
* Tests and test utilities. Note that I didn't change legacy React
test fixtures because I assumed it was good for those files to
act just like old React, including coercion behavior.
* Build scripts
* Dev tools package - In addition to switching to `String`, I also
removed special-case code for coercing symbols which is now
unnecessary.
* Add DEV-only string coercion checks to prod files
This commit adds DEV-only function calls to to check if string coercion
using `'' + value` will throw, which it will if the value is a Temporal
object or a symbol because those types can't be added with `+`.
If it will throw, then in DEV these checks will show a console error
to help the user undertsand what went wrong and how to fix the
problem. After emitting the console error, the check functions will
retry the coercion which will throw with a call stack that's easy (or
at least easier!) to troubleshoot because the exception happens right
after a long comment explaining the issue. So whether the user is in
a debugger, looking at the browser console, or viewing the in-browser
DEV call stack, it should be easy to understand and fix the problem.
In most cases, the safe-string-coercion ESLint rule is smart enough to
detect when a coercion is safe. But in rare cases (e.g. when a coercion
is inside a ternary) this rule will have to be manually disabled.
This commit also switches error-handling code to use `String(value)`
for coercion, because it's bad to crash when you're trying to build
an error message or a call stack! Because `String()` is usually
disallowed by the `safe-string-coercion` ESLint rule in production
code, the rule must be disabled when `String()` is used.
* Remove pushEmpty
This is only used to support the assignID mechanism.
* Remove assignID mechanism
This effectively isn't used anyway because we always insert a dummy tag
into the fallback.
* Emit the template tag with an ID directly in pending boundaries
This ensures that assigning the ID is deterministic since it's done during
writing.
This also avoids emitting it for client rendered boundaries that start as
client rendered since we never need to refer to them.
* Move lazy ID initialization to the core implementation
We never need an ID before we write a pending boundary. This also ensures
that ID generation is deterministic by moving it to the write phase.
* Simplify the inserted scripts
We can assume that there are no text nodes before the template tag so this
simplifies the script that finds the comment node. It should be the direct
previous child.
* Re-add old Fabric Offscreen impl behind flag
There's a chance that #21960 will affect layout in a way that we don't
expect, so I'm adding back the old implementation so we can toggle the
feature with a flag.
The flag should read from the ReactNativeFeatureFlags shim so that we
can change it at runtime. I'll do that separately.
* Import dynamic RN flags from external module
Internal feature flags that we wish to control with a GK can now be
imported from an external module, which I've called
"ReactNativeInternalFeatureFlags".
We'll need to add this module to the downstream repo.
We can't yet use this in our tests, because we don't have a test
configuration that runs against the React Native feature flags fork. We
should set up that up the same way we did for www.
* Add reparenting invariant to React Noop
Fabric does not allow nodes to be reparented, so I added the equivalent
invariant to React Noop's so we can catch regressions.
This causes some tests to fail, which I'll fix in the next step.
* Fix: Use getOffscreenContainerProps
The type of these props is different per renderer. An oversight
from #21960. Unfortunately wasn't caught by Flow because fiber props
are `any`-typed.
* [Fabric] Fix reparenting in legacy Suspense mount
Fixes a weird case during legacy Suspense mount where the offscreen host
container of a tree that suspends during initial mount is recreated
instead of cloned, since there's no current fiber to clone from.
Fabric considers this a reparent even though the parent from the first
pass never committed.
Instead we can override the props from the first pass before the
container completes. It's a bit of a hack, but no more so than the rest
of the legacy root Suspense implementation — the hacks are designed
to make it usable by non-strict mode-compliant trees.
* Fix type of Offscreen props argument
Fixes an oversight from a previous refactor. The fiber that wraps
a Suspense component's children used to be a Fragment but now it's on
Offscreen fiber, so its props type has changed. There's a special
hydration path where I forgot to update this. This isn't observable
because we don't ever end up rendering this particular fiber (because
the Suspense boundary is in its fallback state) but we should fix it
anyway to avoid a potential regression in the future.
* Extract createOffscreenFromFiber logic
...into a new method called `createWorkInProgressOffscreenFiber`. Just
for symmetry with `updateWorkInProgressOffscreenFiber`. Doesn't change
any behavior.
* [Fabric] Use container node to hide/show tree
This changes how we hide and show the contents of Offscreen boundaries
in the React Fabric renderer (persistent mode), and also Suspense
boundaries which use the same feature.=
The way it used to work was that when a boundary is hidden, in the
complete phase, instead of calling the normal `cloneInstance` method
inside `appendAllChildren`, we would call a forked method called
`cloneHiddenInstance` for each of the nearest host nodes within the
subtree. This design was largely based on how it works in React DOM
(mutation mode), where instead of cloning the nearest host nodes, we
mutate their `style.display` property.
The motivation for doing it this way in React DOM was because there's no
built-in browser API for hiding a collection of DOM nodes without
affecting their layout.
In Fabric, however, there is no such limitation, so we can instead wrap
in an extra host node and apply a hidden style.
The immediate motivation for this change is that Fabric on Android has a
view pooling mechanism for instances that relies on the assumption that
a current Fiber that is cloned and replaced by a new Fiber will never
appear in a future commit. When this assumption is broken, it may cause
crashes. In the current implementation, that can indeed happen when a
node that was previously hidden is toggled back to visible. Although
this change sidesteps the issue, we may introduce in other features in
the future that would benefit from being able to revert back to an older
node without cloning it again, such as animations.
The way I've implemented this is to insert an additional HostComponent
fiber as the child of each OffscreenComponent. The extra fiber is not
ideal — the way I'd prefer to do it is to attach the host instance to
the OffscreenComponent. However, the native Fabric implementation
currently expects a 1:1 correspondence between HostComponents and host
instances, so I've deferred that optimization to a future PR to derisk
fixing the Fabric pooling crash. I left a TODO in the host config with a
description of the remaining steps, but this alone should be sufficient
to unblock.
* Re-land recent flushSync changes
Adds back #21776 and #21775, which were removed due to an internal
e2e test failure.
Will attempt to fix in subsequent commits.
* Failing test: Legacy mode sync passive effects
In concurrent roots, if a render is synchronous, we flush its passive
effects synchronously. In legacy roots, we don't do this because all
updates are synchronous — so we need to flush at the beginning of the
next event. This is how `discreteUpdates` worked.
* Flush legacy passive effects at beginning of event
Fixes test added in previous commit.
There's a weird quirk leftover from the old Stack (pre-Fiber)
implementation where the initial mount of a leagcy (ReactDOM.render)
root is flushed synchronously even inside `batchedUpdates`.
The original workaround for this was an internal method called
`unbatchedUpdates`. We've since added another API that works almost the
same way, `flushSync`.
The only difference is that `unbatchedUpdates` would not cause other
pending updates to flush too, only the newly mounted root. `flushSync`
flushes all pending sync work across all roots. This was to preserve
the exact behavior of the Stack implementation.
But since it's close enough, let's just use `flushSync`. It's unlikely
anyone's app accidentally relies on this subtle difference, and the
legacy API is deprecated in 18, anyway.
* Replace flushDiscreteUpdates with flushSync
flushDiscreteUpdates is almost the same as flushSync. It forces passive
effects to fire, because of an outdated heuristic, which isn't ideal but
not that important.
Besides that, the only remaining difference between flushDiscreteUpdates
and flushSync is that flushDiscreteUpdates does not warn if you call it
from inside an effect/lifecycle. This is because it might get triggered
by a nested event dispatch, like `el.focus()`.
So I added a new method, flushSyncWithWarningIfAlreadyRendering, which
is used for the public flushSync API. It includes the warning. And I
removed the warning from flushSync, so the event system can call that
one. In production, flushSyncWithWarningIfAlreadyRendering gets inlined
to flushSync, so the behavior is identical.
Another way of thinking about this PR is that I renamed flushSync to
flushSyncWithWarningIfAlreadyRendering and flushDiscreteUpdates to
flushSync (and fixed the passive effects thing). The point is to prevent
these from subtly diverging in the future.
* Invert so the one with the warning is the default one
To make Seb happy
* Move internal version of act to shared module
No reason to have three different copies of this anymore.
I've left the the renderer-specific `act` entry points because legacy
mode tests need to also be wrapped in `batchedUpdates`. Next, I'll update
the tests to use `batchedUpdates` manually when needed.
* Migrates tests to use internal module directly
Instead of the `unstable_concurrentAct` exports. Now we can drop those
from the public builds.
I put it in the jest-react package since that's where we put our other
testing utilities (like `toFlushAndYield`). Not so much so it can be
consumed publicly (nobody uses that package except us), but so it works
with our build tests.
* Remove unused internal fields
These were used by the old act implementation. No longer needed.
Currently, in a React 18 root, `act` only works if you mock the
Scheduler package. This was because we didn't want to add additional
checks at runtime.
But now that the `act` testing API is dev-only, we can simplify its
implementation.
Now when an update is wrapped with `act`, React will bypass Scheduler
entirely and push its tasks onto a special internal queue. Then, when
the outermost `act` scope exists, we'll flush that queue.
I also removed the "wrong act" warning, because the plan is to move
`act` to an isomorphic entry point, simlar to `startTransition`. That's
not directly related to this PR, but I didn't want to bother
re-implementing that warning only to immediately remove it.
I'll add the isomorphic API in a follow up.
Note that the internal version of `act` that we use in our own tests
still depends on mocking the Scheduler package, because it needs to work
in production. I'm planning to move that implementation to a shared
(internal) module, too.
* Wire up DOM legacy build
* Hack to filter extra comments for testing purposes
* Use string concat in renderToString
I think this might be faster. We could probably use a combination of this
technique in the stream too to lower the overhead.
* Error if we can't complete the root synchronously
Maybe this should always error but in the async forms we can just delay
the stream until it resolves so it does have some useful semantics.
In the synchronous form it's never useful though. I'm mostly adding the
error because we're testing this behavior for renderToString specifically.
* Gate memory leak tests of internals
These tests don't translate as is to the new implementation and have been
ported to the Fizz tests separately.
* Enable Fizz legacy mode in stable
* Add wrapper around the ServerFormatConfig for legacy mode
This ensures that we can inject custom overrides without negatively
affecting the new implementation.
This adds another field for static mark up for example.
* Wrap pushTextInstance to avoid emitting comments for text in static markup
* Don't emit static mark up for completed suspense boundaries
Completed and client rendered boundaries are only marked for the client
to take over.
Pending boundaries are still supported in case you stream non-hydratable
mark up.
* Wire up generateStaticMarkup to static API entry points
* Mark as renderer for stable
This shouldn't affect the FB one ideally but it's done with the same build
so let's hope this works.
