This wires up the use of `async_hooks` in the Node build (as well as the
Edge build when a global is available) in DEV mode only. This will be
used to track debug info about what suspended during an RSC pass.
Enabled behind a flag for now.
Postponing in a promise that is being serialized to the client from the
server should be possible however prior to this change Flight treated
this case like an error rather than a postpone. This fix adds support
for postponing in this position and adds a test asserting you can
successfully prerender the root if you unwrap this promise inside a
suspense boundary.
Now that we no longer support Server Context, we can now deduplicate
objects. It's not completely safe for useId but only in the same way as
it's not safe if you reuse elements on the client, so it's not a new
issue.
This also solves cyclic object references.
The issue is that we prefer to inline objects into a plain JSON format
when an object is not going to get reused. In this case the object
doesn't have an id. We could potentially serialize a reference to an
existing model + a path to it but it bloats the format and complicates
the client.
In a smarter flush phase like we have in Fizz we could choose to inline
or outline depending on what we've discovered so far before a flush. We
can't do that here since we use native stringify. However, even in that
solution you might not know that you're going to discover the same
object later so it's not perfect deduping anyway.
Instead, I use a heuristic where I mark previously seen objects and if I
ever see that object again, then I'll outline it. The idea is that most
objects are just going to be emitted once and if it's more than once
it's fairly likely you have a shared reference to it somewhere and it
might be more than two.
The third object gets deduplicated (or "detriplicated").
It's not a perfect heuristic because when we write the second object we
will have already visited all the nested objects inside of it, which
causes us to outline every nested object too even those weren't
reference more than by that parent. Not sure how to solve for that.
If we for some other reason outline an object such as if it suspends,
then it's truly deduplicated since it already has an id.
We only allow plain objects that can be faithfully serialized and
deserialized through JSON to pass through the serialization boundary.
It's a bit too expensive to do all the possible checks in production so
we do most checks in DEV, so it's still possible to pass an object in
production by mistake. This is currently exaggerated by frameworks
because the logs on the server aren't visible enough. Even so, it's
possible to do a mistake without testing it in DEV or just testing a
conditional branch. That might have security implications if that object
wasn't supposed to be passed.
We can't rely on only checking if the prototype is `Object.prototype`
because that wouldn't work with cross-realm objects which is
unfortunate. However, if it isn't, we can check wether it has exactly
one prototype on the chain which would catch the common error of passing
a class instance.
The jsx-runtime uses the ReactCurrentDispatcher from shared internals.
Recently this was moved to ReactServerSharedInternals which broke
jsx-runtime. This change moves it back to ReactSharedInternals until we
can come up with a new forking mechanism.
This lets a registered object or value be "tainted", which we block from
crossing the serialization boundary. It's only allowed to stay
in-memory.
This is an extra layer of protection against mistakes of transferring
data from a data access layer to a client. It doesn't provide perfect
protection, because it doesn't trace through derived values and
substrings. So it shouldn't be used as the only security layer but more
layers are better.
`taintObjectReference` is for specific object instances, not any nested
objects or values inside that object. It's useful to avoid specific
objects from getting passed as is. It ensures that you don't
accidentally leak values in a specific context. It can be for security
reasons like tokens, privacy reasons like personal data or performance
reasons like avoiding passing large objects over the wire.
It might be privacy violation to leak the age of a specific user, but
the number itself isn't blocked in any other context. As soon as the
value is extracted and passed specifically without the object, it can
therefore leak.
`taintUniqueValue` is useful for high entropy values such as hashes,
tokens or crypto keys that are very unique values. In that case it can
be useful to taint the actual primitive values themselves. These can be
encoded as a string, bigint or typed array. We don't currently check for
this value in a substring or inside other typed arrays.
Since values can be created from different sources they don't just
follow garbage collection. In this case an additional object must be
provided that defines the life time of this value for how long it should
be blocked. It can be `globalThis` for essentially forever, but that
risks leaking memory for ever when you're dealing with dynamic values
like reading a token from a database. So in that case the idea is that
you pass the object that might end up in cache.
A request is the only thing that is expected to do any work. The
principle is that you can derive values from out of a tainted
entry during a request. Including stashing it in a per request cache.
What you can't do is store a derived value in a global module level
cache. At least not without also tainting the object.
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.
We currently abort a stream either it's explicitly told to abort (e.g.
by an abortsignal). In this case we still finish writing what we have as
well as instructions for the client about what happened so it can
trigger fallback cases and log appropriately.
We also abort a request if the stream itself cancels. E.g. if you can't
write anymore. In this case we should not write anything to the outgoing
stream since it's supposed to be closed already now. However, we should
still abort the request so that more work isn't performed and so that we
can log the reason for it to the onError callback.
We should also not do any work after aborting.
There we need to stop the "flow" of bytes - so I call stopFlowing in the
cancel case before aborting.
The tests were testing this case but we had changed the implementation
to only start flowing at initial read (pull) instead of start like we
used to. As a result, it was no longer covering this case. We have to
call reader.read() in the tests to start the flow so that we need to
cancel it.
We also were missing a final assertion on the error logs and since we
were tracking them explicitly the extra error was silenced.
When Float was first developed the internal implementation and external
interface were the same. This is problematic for a few reasons. One, the
public interface is typed but it is also untrusted and we should not
assume that it is actually respected. Two, the internal implementations
can get called from places other than the the public interface and
having to construct an options argument that ends up being destructured
to process the request is computationally wasteful and may limit JIT
optimizations to some degree. Lastly, the wire format was not as
compressed as it could be and it was untyped.
This refactor aims to address that by separating the public interface
from the internal implementations so we can solve these challenges and
also make it easier to change Float in the future
* The internal dispatcher method preinit is now preinitStyle and
preinitScript.
* The internal dispatcher method preinitModule is now
preinitModuleScript in anticipation of different implementations for
other module types in the future.
* The wire format is explicitly typed and only includes options if they
are actually used omitting undefined and nulls.
* Some function arguments are not options even if they are optional. For
instance precedence can be null/undefined because we deafult it to
'default' however we don't cosnider this an option because it is not
something we transparently apply as props to the underlying instance.
* Fixes a problem with keying images in flight where srcset and sizes
were not being taken into account.
* Moves argument validation into the ReactDOMFloat file where it is
shared with all runtimes that expose these methods
* Fixes crossOrigin serialization to use empty string except when
'use-credentials'
Just moving some internal code around again.
I originally encoded what type of work using startRender vs
startPrerender. I had intended to do more forking of the work loop but
we've decided not to go with that strategy. It also turns out that
forking when we start working is actually too late because of a subtle
thing where you can call abort before work begins. Therefore it's
important that starting the work comes later.
This is basically the implementation for the prerender pass.
Instead of forking basically the whole implementation for prerender, I
just add a conditional field on the request. If it's `null` it behaves
like before. If it's non-`null` then instead of triggering client
rendered boundaries it triggers those into a "postponed" state which is
basically just a variant of "pending". It's supposed to be filled in
later.
It also builds up a serializable tree of which path can be followed to
find the holes. This is basically a reverse `KeyPath` tree.
It is unfortunate that this approach adds more code to the regular Fizz
builds but in practice. It seems like this side is not going to add much
code and we might instead just want to merge the builds so that it's
smaller when you have `prerender` and `resume` in the same bundle -
which I think will be common in practice.
This just implements the prerender side, and not the resume side, which
is why the tests have a TODO. That's in a follow up PR.
This adds an experimental `unstable_postpone(reason)` API.
Currently we don't have a way to model effectively an Infinite Promise.
I.e. something that suspends but never resolves. The reason this is
useful is because you might have something else that unblocks it later.
E.g. by updating in place later, or by client rendering.
On the client this works to model as an Infinite Promise (in fact,
that's what this implementation does). However, in Fizz and Flight that
doesn't work because the stream needs to end at some point. We don't
have any way of knowing that we're suspended on infinite promises. It's
not enough to tag the promises because you could await those and thus
creating new promises. The only way we really have to signal this
through a series of indirections like async functions, is by throwing.
It's not 100% safe because these values can be caught but it's the best
we can do.
Effectively `postpone(reason)` behaves like a built-in [Catch
Boundary](https://github.com/facebook/react/pull/26854). It's like
`raise(Postpone, reason)` except it's built-in so it needs to be able to
be encoded and caught by Suspense boundaries.
In Flight and Fizz these behave pretty much the same as errors. Flight
just forwards it to retrigger on the client. In Fizz they just trigger
client rendering which itself might just postpone again or fill in the
value. The difference is how they get logged.
In Flight and Fizz they log to `onPostpone(reason)` instead of
`onError(error)`. This log is meant to help find deopts on the server
like finding places where you fall back to client rendering. The reason
that you pass in is for that purpose to help the reason for any deopts.
I do track the stack trace in DEV but I don't currently expose it to
`onPostpone`. This seems like a limitation. It might be better to expose
the Postpone object which is an Error object but that's more of an
implementation detail. I could also pass it as a second argument.
On the client after hydration they don't get passed to
`onRecoverableError`. There's no global `onPostpone` API to capture
postponed things on the client just like there's no `onError`. At that
point it's just assumed to be intentional. It doesn't have any `digest`
or reason passed to the client since it's not logged.
There are some hacky solutions that currently just tries to reuse as
much of the existing code as possible but should be more properly
implemented.
- Fiber is currently just converting it to a fake Promise object so that
it behaves like an infinite Promise.
- Fizz is encoding the magic digest string `"POSTPONE"` in the HTML so
we know to ignore it but it should probably just be something neater
that doesn't share namespace with digests.
Next I plan on using this in the `/static` entry points for additional
features.
Why "postpone"? It's basically a synonym to "defer" but we plan on using
"defer" for other purposes and it's overloaded anyway.
Since we no longer have externally configured "process" methods, I just
inlined all of those.
The main thing in this refactor is that I just inlined all the error
branches into just `emitErrorChunk`. I'm not sure why it was split up an
repeated before but this seems simpler. I need it since I'm going to be
doing similar copies of this.
This uses the same mechanism as [large
strings](https://github.com/facebook/react/pull/26932) to encode chunks
of length based binary data in the RSC payload behind a flag.
I introduce a new BinaryChunk type that's specific to each stream and
ways to convert into it. That's because we sometimes need all chunks to
be Uint8Array for the output, even if the source is another array buffer
view, and sometimes we need to clone it before transferring.
Each type of typed array is its own row tag. This lets us ensure that
the instance is directly in the right format in the cached entry instead
of creating a wrapper at each reference. Ideally this is also how
Map/Set should work but those are lazy which complicates that approach a
bit.
We assume both server and client use little-endian for now. If we want
to support other modes, we'd convert it to/from little-endian so that
the transfer protocol is always little-endian. That way the common
clients can be the fastest possible.
So far this only implements Server to Client. Still need to implement
Client to Server for parity.
NOTE: This is the first time we make RSC effectively a binary format.
This is not compatible with existing SSR techniques which serialize the
stream as unicode in the HTML. To be compatible, those implementations
would have to use base64 or something like that. Which is what we'll do
when we move this technique to be built-in to Fizz.
We already support these in the sense that they're Iterable so they just
get serialized as arrays. However, these are part of the Structured
Clone algorithm [and should be
supported](https://github.com/facebook/react/issues/25687).
The encoding is simply the same form as the Iterable, which is
conveniently the same as the constructor argument. The difference is
that now there's a separate reference to it.
It's a bit awkward because for multiple reference to the same value,
it'd be a new Map/Set instance for each reference. So to encode sharing,
it needs one level of indirection with its own ID. That's not really a
big deal for other types since they're inline anyway - but since this
needs to be outlined it creates possibly two ids where there only needs
to be one or zero.
One variant would be to encode this in the row type. Another variant
would be something like what we do for React Elements where they're
arrays but tagged with a symbol. For simplicity I stick with the simple
outlining for now.
This introduces a Text row (T) which is essentially a string blob and
refactors the parsing to now happen at the binary level.
```
RowID + ":" + "T" + ByteLengthInHex + "," + Text
```
Today, we encode all row data in JSON, which conveniently never has
newline characters and so we use newline as the line terminator. We
can't do that if we pass arbitrary unicode without escaping it. Instead,
we pass the byte length (in hexadecimal) in the leading header for this
row tag followed by a comma.
We could be clever and use fixed or variable-length binary integers for
the row id and length but it's not worth the more difficult
debuggability so we keep these human readable in text.
Before this PR, we used to decode the binary stream into UTF-8 strings
before parsing them. This is inefficient because sometimes the slices
end up having to be copied so it's better to decode it directly into the
format. The follow up to this is also to add support for binary data and
then we can't assume the entire payload is UTF-8 anyway. So this
refactors the parser to parse the rows in binary and then decode the
result into UTF-8. It does add some overhead to decoding on a per row
basis though.
Since we do this, we need to encode the byte length that we want decode
- not the string length. Therefore, this requires clients to receive
binary data and why I had to delete the string option.
It also means that I had to add a way to get the byteLength from a chunk
since they're not always binary. For Web streams it's easy since they're
always typed arrays. For Node streams it's trickier so we use the
byteLength helper which may not be very efficient. Might be worth
eagerly encoding them to UTF8 - perhaps only for this case.
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.
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
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
This adds `encodeReply` to the Flight Client and `decodeReply` to the
Flight Server.
Basically, it's a reverse Flight. It serializes values passed from the
client to the server. I call this a "Reply". The tradeoffs and
implementation details are a bit different so it requires its own
implementation but is basically a clone of the Flight Server/Client but
in reverse. Either through callServer or ServerContext.
The goal of this project is to provide the equivalent serialization as
passing props through RSC to client. Except React Elements and
Components and such. So that you can pass a value to the client and back
and it should have the same serialization constraints so when we add
features in one direction we should mostly add it in the other.
Browser support for streaming request bodies are currently very limited
in that only Chrome supports it. So this doesn't produce a
ReadableStream. Instead `encodeReply` produces either a JSON string or
FormData. It uses a JSON string if it's a simple enough payload. For
advanced features it uses FormData. This will also let the browser
stream things like File objects (even though they're not yet supported
since it follows the same rules as the other Flight).
On the server side, you can either consume this by blocking on
generating a FormData object or you can stream in the
`multipart/form-data`. Even if the client isn't streaming data, the
network does. On Node.js busboy seems to be the canonical library for
this, so I exposed a `decodeReplyFromBusboy` in the Node build. However,
if there's ever a web-standard way to stream form data, or if a library
wins in that space we can support it. We can also just build a multipart
parser that takes a ReadableStream built-in.
On the server, server references passed as arguments are loaded from
Node or Webpack just like the client or SSR does. This means that you
can create higher order functions on the client or server. This can be
tokenized when done from a server components but this is a security
implication as it might be tempting to think that these are not fungible
but you can swap one function for another on the client. So you have to
basically treat an incoming argument as insecure, even if it's a
function.
I'm not too happy with the naming parity:
Encode `server.renderToReadableStream` Decode: `client.createFromFetch`
Decode `client.encodeReply` Decode: `server.decodeReply`
This is mainly an implementation details of frameworks but it's annoying
nonetheless. This comes from that `renderToReadableStream` does do some
"rendering" by unwrapping server components etc. The `create` part comes
from the parity with Fizz/Fiber where you `render` on the server and
`create` a root on the client.
Open to bike-shedding this some more.
---------
Co-authored-by: Josh Story <josh.c.story@gmail.com>
## Summary
Adds support for returning `undefined` from Server Components.
Also fixes a bug where rendering an empty fragment would throw the same
error as returning undefined.
## How did you test this change?
- [x] test failed with same error message I got when returning undefined
from Server Components in a Next.js app
- [x] test passes after adding encoding for `undefined`
This is just moving some stuff around and renaming things.
This tuple is opaque to the Flight implementation and we should probably
encode it separately as a single string instead of a model object.
The term "Metadata" isn't the same as when used for ClientReferences so
it's not really the right term anyway.
I also made it optional since a bound function with no arguments bound
is technically different than a raw instance of that function (it's a
clone).
I also renamed the type ReactModel to ReactClientValue. This is the
generic serializable type for something that can pass through the
serializable boundary from server to client. There will be another one
for client to server.
I also filled in missing classes and ensure the serializable sub-types
are explicit. E.g. Array and Thenable.
We support any super type of anything that we can serialize. Meaning
that as long as the Type that's passed through is less precise, it means
that we can encoded it as any subtype and therefore the incoming type
doesn't have to be the subtype in that case. Basically, as long as
you're only passing through an `Iterable<T>` in TypeScript, then you can
pass any `Iterable<T>` and we'll treat it as an array.
For example we support Promises *and* Thenables but both are encoded as
Promises.
We support Arrays and since Arrays are also Iterables, we can support
Iterables.
For @wongmjane
Previously when a called server reference function was rejected, the
emitted error chunk was not flushed, and the request was not properly
closed.
Co-authored-by: Sebastian Markbage <sebastian@calyptus.eu>
We always look up these references in a map so it doesn't matter what
their value is. It could be a hash for example.
The loaders now encode a single $$id instead of filepath + name.
This changes the react-client-manifest to have a single level. The value
inside the map is still split into module id + export name because
that's what gets looked up in webpack.
The react-ssr-manifest is still two levels because that's a reverse
lookup.
This is the first of a series of PRs, that let you pass functions, by
reference, to the client and back. E.g. through Server Context. It's
like client references but they're opaque on the client and resolved on
the server.
To do this, for security, you must opt-in to exposing these functions to
the client using the `"use server"` directive. The `"use client"`
directive lets you enter the client from the server. The `"use server"`
directive lets you enter the server from the client.
This works by tagging those functions as Server References. We could
potentially expand this to other non-serializable or stateful objects
too like classes.
This only implements server->server CJS imports and server->server ESM
imports. We really should add a loader to the webpack plug-in for
client->server imports too. I'll leave closures as an exercise for
integrators.
You can't "call" a client reference on the server, however, you can
"call" a server reference on the client. This invokes a callback on the
Flight client options called `callServer`. This lets a router implement
calling back to the server. Effectively creating an RPC. This is using
JSON for serializing those arguments but more utils coming from
client->server serialization.
This lets you pass Promises from server components to client components
and `use()` them there.
We still don't support Promises as children on the client, so we need to
support both. This will be a lot simpler when we remove the need to
encode children as lazy since we don't need the lazy encoding anymore
then.
I noticed that this test failed because we don't synchronously resolve
instrumented Promises if they're lazy. The second fix calls `.then()`
early to ensure that this lazy initialization can happen eagerly. ~It
felt silly to do this with an empty function or something, so I just did
the attachment of ping listeners early here. It's also a little silly
since they will ping the currently running render for no reason if it's
synchronously available.~ EDIT: That didn't work because a ping might
interrupt the current render. Probably need a bigger refactor.
We could add another extension but we've already taken a lot of
liberties with the Promise protocol. At least this is one that doesn't
need extension of the protocol as much. Any sub-class of promises could
do this.
This is just shifting around some encoding strategies for Flight in
preparation for more types.
```
S1:"react.suspense"
J2:["$", "$1", {children: "@3"}]
J3:"Hello"
```
```
1:"$Sreact.suspense"
2:["$", "$1", {children: "$L3"}]
3:"Hello"
```
The old version of prettier we were using didn't support the Flow syntax
to access properties in a type using `SomeType['prop']`. This updates
`prettier` and `rollup-plugin-prettier` to the latest versions.
I added the prettier config `arrowParens: "avoid"` to reduce the diff
size as the default has changed in Prettier 2.0. The largest amount of
changes comes from function expressions now having a space. This doesn't
have an option to preserve the old behavior, so we have to update this.
This renames Module References to Client References, since they are in
the server->client direction.
I also changed the Proxies exposed from the `node-register` loader to
provide better error messages. Ideally, some of this should be
replicated in the ESM loader too but neither are the source of truth.
We'll replicate this in the static form in the Next.js loaders. cc
@huozhi @shuding
- All references are now functions so that when you call them on the
server, we can yield a better error message.
- References that are themselves already referring to an export name are
now proxies that error when you dot into them.
- `use(...)` can now be used on a client reference to unwrap it server
side and then pass a reference to the awaited value.
These suppressions are no longer required.
Generated using:
```sh
flow/tool update-suppressions .
```
followed by adding back 1 or 2 suppressions that were only triggered in
some configurations.
This enables the "exact_empty_objects" setting for Flow which makes
empty objects exact instead of building up the type as properties are
added in code below. This is in preparation to Flow 191 which makes this
the default and removes the config.
More about the change in the Flow blog
[here](https://medium.com/flow-type/improved-handling-of-the-empty-object-in-flow-ead91887e40c).
This setting is an incremental path to the next Flow version enforcing
type annotations on most functions (except some inline callbacks).
Used
```
node_modules/.bin/flow codemod annotate-functions-and-classes --write .
```
to add a majority of the types with some hand cleanup when for large
inferred objects that should just be `Fiber` or weird constructs
including `any`.
Suppressed the remaining issues.
Builds on #25918
The old (unstable) mechanism for suspending was to throw a promise. The
purpose of throwing is to interrupt the component's execution, and also
to signal to React that the interruption was caused by Suspense as
opposed to some other error.
A flaw is that throwing is meant to be an implementation detail — if
code in userspace catches the promise, it can lead to unexpected
behavior.
With `use`, userspace code does not throw promises directly, but `use`
itself still needs to throw something to interrupt the component and
unwind the stack.
The solution is to throw an internal error. In development, we can
detect whether the error was caught by a userspace try/catch block and
log a warning — though it's not foolproof, since a clever user could
catch the object and rethrow it later.
The error message includes advice to move `use` outside of the try/catch
block.
I did not yet implement the warning in Flight.
Same as #25537 but for Flight.
I was going to wait to do this later because the temporary
implementation of async components uses some of the same code that
non-used wakables do, but it's not so bad. I just had to inline one bit
of code, which we'll remove when we unify the implementation with `use`.
This extends the scope of the cache and fetch instrumentation using
AsyncLocalStorage for microtasks. This is an intermediate step. It sets
up the dispatcher only once. This is unique to RSC because it uses the
react.shared-subset module for its shared state.
Ideally we should support multiple renderers. We should also have this
take over from an outer SSR's instrumented fetch. We should also be able
to have a fallback to global state per request where AsyncLocalStorage
doesn't exist and then the whole client-side solutions. I'm still
figuring out the right wiring for that so this is a temporary hack.
To derisk the rollout of `use`, and simplify the implementation, this
reverts the yield-to-microtasks behavior for promises that are thrown
directly (as opposed to being unwrapped by `use`).
We may add this back later. However, the plan is to deprecate throwing a
promise directly and migrate all existing Suspense code to `use`, so the
extra code probably isn't worth it.
* Facebook -> Meta in copyright
rg --files | xargs sed -i 's#Copyright (c) Facebook, Inc. and its affiliates.#Copyright (c) Meta Platforms, Inc. and affiliates.#g'
* Manual tweaks
* Print built-in specific error message for toJSON
This is a better message for Date.
Also, format the message to highlight the affected prop.
* Describe error messages using JSX elements in DEV
We don't have access to the grand parent objects on the stack so we stash
them on weakmaps so we can access them while printing error messages.
Might be a bit slow.
* Capitalize Server/Client Component
* Special case errror messages for children of host components
These are likely meant to be text content if they're not a supported object.
* Update error messages
This is a temporary step until we allow Promises everywhere.
Currently this serializes to a Lazy which can then be consumed in this same
slot by the client.
* 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.
- method unbinding is no longer supported in Flow for soundness, this added a bunch of suppressions
- Flow now prevents objects to be supertypes of interfaces/classes
ghstack-source-id: d7749cbad8
Pull Request resolved: https://github.com/facebook/react/pull/25412
Sebastian Markbåge
Josh Story
Jan Kassens
Sophie Alpert
Sebastian Silbermann
Hendrik Liebau
Andrew Clark