Commit Graph
20872 Commits
Author SHA1 Message Date
Ricky 8a8e9a7edf move devtools notify to different channel (#34476) 2025-09-12 14:14:25 -04:00
RickyandSebastian Sebbie Silbermann 68f00c901c Release Activity in Canary (#34374)
## Overview

This PR ships `<Activity />` to the `react@canary` release channel for
final feedback and prepare for semver stable release.

## What this means

Shipping `<Activity />` to canary means it has gone through extensive
testing in production, we are confident in the stability of the feature,
and we are preparing to release it in a future semver stable version.

Libraries and frameworks following the [Canary
Workflow](https://react.dev/blog/2023/05/03/react-canaries) should begin
implementing and testing the feature.

## Why we follow the Canary Workflow

To prepare for semver stable, libraries should test canary features like
`<Activity>` with `react@canary` to confirm compatibility and prepare
for the next semver release in a myriad of environments and
configurations used throughout the React ecosystem. This provides
libraries with ample time to catch any issues we missed before slamming
them with problems in the wider semver release.

Since these features have already gone through extensive production
testing, and we are confident they are stable, frameworks following the
[Canary Workflow](https://react.dev/blog/2023/05/03/react-canaries) can
also begin adopting canary features like `<Activity />`.

This adoption is similar to how different Browsers implement new
proposed browser features before they are added to the standard. If a
frameworks adopts a canary feature, they are committing to stability for
their users by ensuring any API changes before a semver stable release
are opaque and non-breaking to their users.

Apps not using a framework are also free to adopt canary features like
Activity as long as they follow the [Canary
Workflow](https://react.dev/blog/2023/05/03/react-canaries), but we
generally recommend waiting for a semver stable release unless you have
the capacity to commit to following along with the canary changes and
debugging library compatibility issues.

Waiting for semver stable means you're able to benefit from libraries
testing and confirming support, and use semver as signal for which
version of a library you can use with support of the feature.

## Docs 

Check out the ["React Labs: View Transitions, Activity, and
more"](https://react.dev/blog/2025/04/23/react-labs-view-transitions-activity-and-more#activity)
blog post, and [the new docs for
`<Activity>`](https://react.dev/reference/react/Activity) for more info.

## TODO
- [x] Bump Activity docs to Canary
https://github.com/reactjs/react.dev/pull/7974

---------

Co-authored-by: Sebastian Sebbie Silbermann <sebastian.silbermann@vercel.com>
2025-09-12 12:47:40 -04:00
Sebastian Markbåge 93d7aa69b2 [Fiber] Add context for the display: inline warning (#34461)
This warning doesn't execute within any particular context so doesn't
have a stack.

Pick the fiber of the child if it exists, otherwise the parent.

<img width="846" height="316" alt="Screenshot 2025-09-10 at 12 38 28 PM"
src="https://github.com/user-attachments/assets/7ab283a9-6e11-428d-9def-38f80ca958ef"
/>
2025-09-12 11:55:25 -04:00
Sebastian Markbåge 20e5431747 [Flight][Fiber] Encode owner in the error payload in dev and use it as the Error's Task (#34460)
When we report an error we typically log the owner stack of the thing
that caught the error. Similarly we restore the `console.createTask`
scope of the catching component when we call `reportError` or
`console.error`.

We also have a special case if something throws during reconciliation
which uses the Server Component task as far as we got before we threw.


https://github.com/facebook/react/blob/main/packages/react-reconciler/src/ReactChildFiber.js#L1952-L1960

Chrome has since fixed it (on our request) that the Error constructor
snapshots the Task at the time the constructor was created and logs that
in `reportError`. This is a good thing since it means we get a coherent
stack. Unfortunately, it means that the fake Errors that we create in
Flight Client gets a snapshot of the task where they were created so
when they're reported in the console they get the root Task instead of
the Task of the handler of the error.

Ideally we'd transfer the Task from the server and restore it. However,
since we don't instrument the Error object to snapshot the owner and we
can't read the native Task (if it's even enabled on the server) we don't
actually have a correct snapshot to transfer for a Server Component
Error. However, we can use the parent's task for where the error was
observed by Flight Server and then encode that as a pseudo owner of the
Error.

Then we use this owner as the Task which the Error is created within.
Now the client snapshots that Task which is reported by `reportError` so
now we have an async stack for Server Component errors again. (Note that
this owner may differ from the one observed by `captureOwnerStack` which
gets the nearest Server Component from where it was caught. We could
attach the owner to the Error object and use that owner when calling
`onCaughtError`/`onUncaughtError`).

Before:

<img width="911" height="57" alt="Screenshot 2025-09-10 at 10 57 54 AM"
src="https://github.com/user-attachments/assets/0446ef96-fad9-4e17-8a9a-d89c334233ec"
/>

After:

<img width="910" height="128" alt="Screenshot 2025-09-10 at 11 06 20 AM"
src="https://github.com/user-attachments/assets/b30e5892-cf40-4246-a588-0f309575439b"
/>

Similarly, there are Errors and warnings created by ChildFiber itself.
Those execute in the scope of the general render of the parent Fiber.
They used to get the scope of the nearest client component parent (e.g.
div in this case) but that's the parent of the Server Component. It
would be too expensive to run every level of reconciliation in its own
task optimistically, so this does it only when we know that we'll throw
or log an error that needs this context. Unfortunately this doesn't
cover user space errors (such as if an iterable errors).

Before:

<img width="903" height="298" alt="Screenshot 2025-09-10 at 11 31 55 AM"
src="https://github.com/user-attachments/assets/cffc94da-8c14-4d6e-9a5b-bf0833b8b762"
/>

After:

<img width="1216" height="252" alt="Screenshot 2025-09-10 at 11 50
54 AM"
src="https://github.com/user-attachments/assets/f85f93cf-ab73-4046-af3d-dd93b73b3552"
/>

<img width="412" height="115" alt="Screenshot 2025-09-10 at 11 52 46 AM"
src="https://github.com/user-attachments/assets/a76cef7b-b162-4ecf-9b0a-68bf34afc239"
/>
2025-09-12 11:55:07 -04:00
Eugene Choi 1a27af3607 [playground] Update the playground UI (#34468)
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## Summary

Updated the UI of the React compiler playground. The config, Input, and
Output panels will now span the viewport width when "Show Internals" is
not toggled on. When "Show Internals" is toggled on, the old vertical
accordion tabs are still used. Going to add support for the "Applied
Configs" tabs underneath the "Config Overrides" tab next.

<!--
Explain the **motivation** for making this change. What existing problem
does the pull request solve?
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## How did you test this change?


https://github.com/user-attachments/assets/b8eab028-f58c-4cb9-a8b2-0f098f2cc262


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2025-09-12 11:43:04 -04:00
Ruslan Lesiutin 0e10ee906e [Reconciler] Set ProfileMode for Host Root Fiber by default in dev (#34432)
Requiring DevTools to be present for dev builds seems like an overkill,
let's enable the instrumentation by default.

Nothing changes for profiling or production artifacts.
2025-09-12 12:20:39 +01:00
Ruslan Lesiutin 0c813c528d [Tracks]: display method name and component name for updates in DEV (#34463)
For every "Update" entry we are going to add properties that will be
displayed when the user clicks on that entry: name of the method that
caused this first update and name of the component where this update
happened.

We could use the name of the component as a deeplink to React DevTools
components panel in the future, once we support stable identificators on
Fibers.

<img width="1444" height="530" alt="Screenshot 2025-09-10 at 18 31 10"
src="https://github.com/user-attachments/assets/7f9af037-2e7f-4e7b-9b7e-bf9f7d5a6e72"
/>
<img width="2088" height="530" alt="Screenshot 2025-09-10 at 18 24 21"
src="https://github.com/user-attachments/assets/f557a173-bd9b-43f7-9333-74066f433ced"
/>
<img width="2088" height="530" alt="Screenshot 2025-09-10 at 18 26 04"
src="https://github.com/user-attachments/assets/ff37d13f-bbe3-4f85-800e-81aa3aed7833"
/>
2025-09-12 11:34:41 +01:00
Sebastian "Sebbie" Silbermann a9ad64c852 [DevTools] Stop mounting empty roots (#34467) 2025-09-11 20:00:53 +02:00
Sebastian "Sebbie" Silbermann 7fc888dde2 [DevTools] Stop recording reorders in disconnected subtrees (#34464) 2025-09-11 19:13:14 +02:00
Sebastian "Sebbie" Silbermann 67415c8c4a [DevTools] Stop using native title for buttons/icons (#34379) 2025-09-11 18:49:35 +02:00
Hendrik Liebau f3a803617e [Flight] Ensure async info owners are outlined properly (#34465)
When we emit objects of type `ReactAsyncInfo`, we need to make sure that
their owners are outlined, using `outlineComponentInfo`. Otherwise we
would end up accidentally emitting stashed fields that are not part of
the transport protocol, specifically `debugStack`, `debugTask`, and
`debugLocation`. This would lead to runtime errors in the client, when
for example, the stack for a `debugLocation` is processed in
`buildFakeCallStack`, but the stack was actually omitted from the RSC
payload, because for those fields we don't ensure that the object limit
is increased by the length of the stack, as we do when we're emitting
the `stack` of a `ReactComponentInfo` object in `outlineComponentInfo`.
2025-09-11 18:10:25 +02:00
Eugene Choi fe84397e81 [compiler][playground] (4/N) Config override panel (#34436)
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  2. Run `yarn` in the repository root.
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4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
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open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
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  10. If you haven't already, complete the CLA.

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## Summary

Removed the old `OVERRIDE` pragma to make the source of truth for config
overrides in the left-hand pane. Now, it will automatically update the
output pane each time there is an edit to the config. The old pragma
format is still supported, but it will be overwritten by the config pane
if they are modifying the same flags. Removed the gating on the config
panel so now all users will automatically be able to view it, but it
will be initially collapsed.

<!--
Explain the **motivation** for making this change. What existing problem
does the pull request solve?
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## How did you test this change?


https://github.com/user-attachments/assets/9d4512b9-e203-4ce0-ae95-dd96ff03bbc1


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their output, screenshots / videos if the pull request changes the user
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How exactly did you verify that your PR solves the issue you wanted to
solve?
  If you leave this empty, your PR will very likely be closed.
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2025-09-11 11:51:32 -04:00
Sebastian "Sebbie" Silbermann b1c519f3d4 [DevTools] Only show boundaries with unique suspenders by default in the timeline (#34397) 2025-09-11 11:33:05 +02:00
Sebastian "Sebbie" Silbermann 8c1501452c [DevTools] Preserve Suspense lineage when clicking through breadcrumbs (#34422) 2025-09-11 10:54:25 +02:00
Joseph Savona bd9e6e0bed [compiler] More flexible/helpful lazy ref initialization (#34449)
Two small QoL improvements inspired by feedback:
* `if (ref.current === undefined) { ref.current = ... }` is now allowed.
* `if (!ref.current) { ref.current = ... }` is still disallowed, but we
emit an extra hint suggesting the `if (!ref.current == null)` pattern.

I was on the fence about the latter. We got feedback asking to allow `if
(!ref.current)` but if your ref stores a boolean value then this would
allow reading the ref in render. The unary form is also less precise in
general due to sketchy truthiness conversions. I figured a hint is a
good compromise.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34449).
* __->__ #34449
* #34424
2025-09-10 13:42:01 -07:00
lauren 835b00908b [compiler] Allow setStates in use{Layout,Insertion}Effect where the set value is derived from a ref (#34462)
@stipsan found this issue where the compiler would bailout on the
`useLayoutEffect` examples in the React docs. While setState in an
effect is typically an anti-pattern due to the fact that it hurts
performance through cascading renders, the one scenario where it _is_
allowed is if the value being set flows from a ref.
2025-09-10 14:56:04 -04:00
Ruslan Lesiutin e2ba45bb39 [DevTools] fix: keep search query in a local sync state (#34423)
When the search query changes, we kick off a transition that updates the
search query in a reducer for TreeContext. The search input is also
using this value for an `input` HTML element.

For a larger applications, sometimes there is a noticeable delay in
displaying the updated search query. This changes the approach to also
keep a local synchronous state that is being updated on a change
callback.
2025-09-10 18:38:47 +01:00
Sebastian Markbåge 886b3d36d7 [DevTools] Show suspended by subtree from Activity to next Suspense boundary (#34438)
Stacked on #34435.

This adds a method to get all suspended by filtered by a specific
Instance. The purpose of this is to power the feature when you filter by
Activity. This would show you the "root" within that Activity boundary.

This works by selecting the nearest Suspense boundary parent and then
filtering its data based on if all the instances for a given I/O info is
within the Activity instance. If something suspended within the Suspense
boundary but outside the Activity it's not included even if it's also
suspending inside the Activity since we assume it would've already been
loaded then.

Right now I wire this up to be a special case when you select an
Activity boundary same as when you select a Suspense boundary in the
Components tab but we could also only use this when you select the root
in the Suspense tab for example.
2025-09-10 09:44:51 -04:00
Sebastian Markbåge 288d428af1 [DevTools] Only show the highest end/byteSize I/O of RSC streams (#34435)
Stacked on #34425.

RSC stream info is split into one I/O entry per chunk. This means that
when a single instance or boundary depends on multiple chunks, it'll
show the same stream multiple times. This makes it so just the last one
is shown.

This is a special case for the name "RSC stream" but ideally we'd more
explicitly model the concept of awaiting only part of a stream.

<img width="667" height="427" alt="Screenshot 2025-09-09 at 2 09 43 PM"
src="https://github.com/user-attachments/assets/890f6f61-4657-4ca9-82fd-df55a696bacc"
/>

Another remaining issue is that it's possible for an intermediate chunk
to be depended on by just a child boundary. In that case that can be
considered a "unique suspender" even though the parent depends on a
later one. Ideally it would dedupe on everything below. Could also model
it as every Promise depends on its chunk and every previous chunk.
2025-09-10 09:08:36 -04:00
Sebastian Markbåge a34c5dff15 Ignore generic InvalidStateError in View Transitions (#34450)
Fixes #34098.

There's an issue in Chrome where the `InvalidStateError` always has the
same error message. The spec doesn't specify the error message to use
but it's more useful to have a specific one for each case like Safari
does.

One reason it's better to have a specific error message is because the
browser console is not the main surface that people look for errors.
Chrome relies on a separate log also in the console. Frameworks has
built-in error dialogs that pop up first and that's where you see the
error and that dialog can't show something specific. Additionally, these
errors can't log something specific to servers in production logging. So
this is a bad strategy.

It's not good to have those error dialogs pop up for non-actionable
errors like when it doesn't start because the document was hidden. Since
we don't have more specific information we have no choice but to hide
all of them. This includes actionable things like duplicate names
(although we also have a React specific warning for that in the common
case).
2025-09-10 09:07:11 -04:00
Sebastian Markbåge 3bf8ab430e Add missing Activity export to development mode (#34439)
This is exported in the prod version of ReactServer experimental but not
the development version so we can't use it in fixtures from Server
Components.
2025-09-09 21:30:37 -04:00
Joseph Savona acada3035f [compiler] Fix false positive hook return mutation error (#34424)
This was fun. We previously added the MaybeAlias effect in #33984 in
order to describe the semantic that an unknown function call _may_ alias
its return value in its result, but that we don't know this for sure. We
record mutations through MaybeAlias edges when walking backward in the
data flow graph, but downgrade them to conditional mutations. See the
original PR for full context.

That change was sufficient for the original case like

```js
const frozen = useContext();
useEffect(() => {
  frozen.method().property = true;
}, [...]);
```

But it wasn't sufficient for cases where the aliasing occured between
operands:

```js
const dispatch = useDispatch();
<div onClick={(e) => {
  dispatch(...e.target.value)
  e.target.value = ...;
}} />
```

Here we would record a `Capture dispatch <- e.target` effect. Then
during processing of the `event.target.value = ...` assignment we'd
eventually _forward_ from `event` to `dispatch` (along a MaybeAlias
edge). But in #33984 I missed that this forward walk also has to
downgrade to conditional.

In addition to that change, we also have to be a bit more precise about
which set of effects we create for alias/capture/maybe-alias. The new
logic is a bit clearer, I think:

* If the value is frozen, it's an ImmutableCapture edge
* If the values are mutable, it's a Capture
* If it's a context->context, context->mutable, or mutable->context,
count it as MaybeAlias.
2025-09-09 14:07:47 -07:00
Sebastian Markbåge 969a9790ad [Flight] Track I/O Entry for the RSC Stream itself (#34425)
One thing that can suspend is the downloading of the RSC stream itself.
This tracks an I/O entry for each Promise (`SomeChunk<T>`) that
represents the request to the RSC stream. As the value we use the
`Response` for `createFromFetch` (or the `ReadableStream` for
`createFromReadableStream`). The start time is when you called those.

Since we're not awaiting the whole stream, each I/O entry represents the
part of the stream up until it got unblocked. However, in a production
environment with TLS packets and buffering in practice the chunks
received by the client isn't exactly at the boundary of each row. It's a
bit longer into larger chunks. From testing, it seems like multiples of
16kb or 64kb uncompressed are common. To simulate a production
environment we group into roughly 64kb chunks if they happen in rapid
sequence. Note that this might be too small to give a good idea because
of the throttle many boundaries might be skipped anyway so this might
show too many.

The React DevTools will see each I/O entry as separate but dedupe if an
outer boundary already depends on the same chunk. This deduping makes it
so that small boundaries that are blocked on the same chunk, don't get
treated as having unique suspenders. If you have a boundary with large
content, then that content will likely be in a separate chunk which is
not in the parent and then it gets marked as.

This is all just an approximation. The goal of this is just to highlight
that very large boundaries will very likely suspend even if they don't
suspend on any I/O on the server. In practice, these boundaries can
float around a lot and it's really any Suspense boundary that might
suspend but some are more likely than others which this is meant to
highlight.

It also just lets you inspect how many bytes needs to be transferred
before you can show a particular part of the content, to give you an
idea that it's not just I/O on the server that might suspend.

If you don't use the debug channel it can be misleading since the data
in development mode stream will have a lot more data in it which leads
to more chunking.

Similarly to "client references" these I/O infos don't have an "env"
since it's the client that has the I/O and so those are excluded from
flushing in the Server performance tracks.

Note that currently the same Response can appear many times in the same
Instance of SuspenseNode in DevTools when there are multiple chunks. In
a follow up I'll show only the last one per Response at any given level.

Note that when a separate debugChannel is used it has its own I/O entry
that's on the `_debugInfo` for the debug chunks in that channel.
However, if everything works correctly these should never leak into the
DevTools UI since they should never be propagated from a debug chunk to
the values waited by the runtime. This is easy to break though.
2025-09-09 16:46:11 -04:00
Joseph Savona 665de2ed28 [compiler] Improve name hints for outlined functions (#34434)
The previous PR added name hints for anonymous functions, but didn't
handle the case of outlined functions. Here we do some cleanup around
function `id` and name hints:
* Make `HIRFunction.id` a ValidatedIdentifierName, which involved some
cleanup of the validation helpers
* Add `HIRFunction.nameHint: string` as a place to store the generated
name hints which are not valid identifiers
* Update Codegen to always use the `id` as the actual function name, and
only use nameHint as part of generating the object+property wrapper for
debug purposes.

This ensures we don't conflate synthesized hints with real function
names. Then, we also update OutlineFunctions to use the function name
_or_ the nameHint as the input to generating a unique identifier. This
isn't quite as nice as the object form since we lose our formatting, but
it's a simple step that gives more context to the developer than `_temp`
does.

Switching to output the object+property lookup form for outlined
functions is a bit more involved, let's do that in a follow-up.
2025-09-09 12:14:09 -07:00
mofeiZandJoe Savona eda778b8ae [compiler] Fix false positive memo validation (alternative) (#34319)
Alternative to #34276

---
(Summary taken from @josephsavona 's #34276)
Partial fix for #34262. Consider this example:

```js
function useInputValue(input) {
  const object = React.useMemo(() => {
    const {value} = transform(input);
    return {value};
  }, [input]);
  return object;
}
```

React Compiler breaks this code into two reactive scopes:
* One for `transform(input)`
* One for `{value}`

When we run ValidatePreserveExistingMemo, we see that the scope for
`{value}` has the dependency `value`, whereas the original memoization
had the dependency `input`, and throw an error that the dependencies
didn't match.

In other words, we're flagging the fact that memoized _better than the
user_ as a problem. The more complete solution would be to validate that
there is a subgraph of reactive scopes with a single input and output
node, where the input node has the same dependencies as the original
useMemo, and the output has the same outputs. That is true in this case,
with the subgraph being the two consecutive scopes mentioned above.

But that's complicated. As a shortcut, this PR checks for any
dependencies that are defined after the start of the original useMemo.
If we find one, we know that it's a case where we were able to memoize
more precisely than the original, and we don't report an error on the
dependency. We still check that the original _output_ value is able to
be memoized, though. So if the scope of `object` were extended, eg with
a call to `mutate(object)`, then we'd still correctly report an error
that we couldn't preserve memoization.

Co-authored-by: Joe Savona <joesavona@fb.com>
2025-09-09 14:26:52 -04:00
Jorge Cabiedes 1836b46fff [compiler] Have react-compiler eslint plugin return a RuleModule (#34421)
Eslint is expecting a map of [string] => RuleModule. Before we were
passing {rule: RuleModule, severity: ErrorSeverity} which was breaking
legacy Eslint configurations
2025-09-09 11:18:37 -07:00
Sebastian "Sebbie" Silbermann eec50b17b3 [Flight] Only use debug component info for parent stacks (#34431) 2025-09-09 19:58:02 +02:00
Joseph Savona a9410fb487 [compiler] Option to infer names for anonymous functions (#34410)
Adds a `@enableNameAnonymousFunctions` feature to infer helpful names
for anonymous functions within components and hooks. The logic is
inspired by a custom Next.js transform, flagged to us by @eps1lon, that
does something similar. Implementing this transform within React
Compiler means that all React (Compiler) users can benefit from more
helpful names when debugging.

The idea builds on the fact that JS engines try to infer helpful names
for anonymous functions (in stack traces) when those functions are
accessed through an object property lookup:

```js
({'a[xyz]': () => {
  throw new Error('hello!')
} }['a[xyz]'])()

// Stack trace:
Uncaught Error: hello!
    at a[xyz] (<anonymous>:1:26) // <-- note the name here
    at <anonymous>:1:60
```

The new NameAnonymousFunctions transform is gated by the above flag,
which is off by default. It attemps to infer names for functions as
follows:

First, determine a "local" name:
* Assigning a function to a named variable uses the variable name.
`const f = () => {}` gets the name "f".
* Passing the function as an argument to a function gets the name of the
function, ie `foo(() => ...)` get the name "foo()", `foo.bar(() => ...)`
gets the name "foo.bar()". Note the parenthesis to help understand that
it was part of a call.
* Passing the function to a known hook uses the name of the hook,
`useEffect(() => ...)` uses "useEffect()".
* Passing the function as a JSX prop uses the element and attr name, eg
`<div onClick={() => ...}` uses "<div>.onClick".

Second, the local name is combined with the name of the outer
component/hook, so the final names will be strings like `Component[f]`
or `useMyHook[useEffect()]`.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34410).
* #34434
* __->__ #34410
2025-09-09 10:22:19 -07:00
Sebastian "Sebbie" Silbermann 6b70072c4f [DevTools] Finalize heuristic for naming unnamed <Suspense> (#34428) 2025-09-09 17:56:26 +02:00
Ruslan Lesiutin b2cff47472 [DevTools] feat: propagate fetchFileWithCaching from initialization options for Fusebox (#34429)
Each integrator: browser extension, Chrome DevTools Frontend fork,
Electron shell must define and provide `fetchFileWithCaching` in order
for DevTools to be able to fetch application resources, such as scripts
or source maps.

More specifically, if this is available, React DevTools will be able to
symbolicate source locations for component frames, owner stacks,
"suspended by" Promises call frames.

This will be available with the next release of React DevTools.
2025-09-09 13:00:53 +01:00
Sebastian "Sebbie" Silbermann 8943025358 [DevTools] Fix handling of host roots on mount (#34400) 2025-09-08 22:53:02 +02:00
Eugene Choiandlauren 3d9d22cbdb [playground] Fix CompilerError mismatch (#34420)
The compiler playground was crashing at any small syntax errors in the
`Input` panel due to updating the `CompilerErrorDetailOptions` type in
#34401. Updated the option to take in a `ErrorCategory` instead.

---------

Co-authored-by: lauren <poteto@users.noreply.github.com>
2025-09-08 15:06:54 -04:00
Eugene Choi d4374b3ae3 [compiler] [playground] Show internals toggle (#34399)
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## Summary

Added a "Show Internals" toggle switch to either show only the Config,
Input, Output, and Source Map tabs, or these tabs + all the additional
compiler options. The open/close state of these tabs will be preserved
(unless on page refresh, which is the same as the currently
functionality).


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## How did you test this change?

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https://github.com/user-attachments/assets/8eb0f69e-360c-4e9b-9155-7aa185a0c018
2025-09-08 14:21:03 -04:00
Joseph Savona 3f2a42a5de [compiler] Handle empty list of eslint suppression rules (#34323)
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34323).
* #34276
* __->__ #34323
2025-09-08 10:33:10 -07:00
Sebastian Markbåge 294c33f34d [Flight] Always initialize a debug info array for each Chunk (#34419)
I'm about to add info for pretty much all of these anyway since they all
depend on the data stream itself.
2025-09-08 12:28:14 -04:00
Sebastian "Sebbie" Silbermann 3fb190f729 [DevTools] Avoid renders of stale Suspense store (#34396) 2025-09-08 11:42:03 +02:00
Joseph Savona f5e96b9740 [compiler] Add missing source locations to statements, expressions (#34406)
Adds missing locations to all the statement kinds that we produce in
codegenInstruction(), and adds generic handling of source locations for
the nodes produced by codegenInstructionValue(). There are definitely
some places where we are still missing a location, but this should
address some of the known issues we've seen such as missing location on
`throw`.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34406).
* #34394
* __->__ #34406
* #34346
2025-09-06 11:14:30 -07:00
lauren 78992521a8 [compiler] Filter out disabled errors from being reported (#34409)
This PR stops error details of severity `ErrorSeverity.Off` from being
reported.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34409).
* __->__ #34409
* #34404
2025-09-06 13:07:23 -04:00
lauren 80d7aa17ad [compiler] Fix error description inconsistency (#34404)
Small fix to make all descriptions consistently printed with a single
period at the end.

Ran `grep -rn "description:" packages/babel-plugin-react-compiler/src
--include="*.ts" --exclude-dir="__tests__" | grep '\.\s*["\`]'` to find
all descriptions ending in a period and manually fixed them.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34404).
* #34409
* __->__ #34404
2025-09-06 13:07:02 -04:00
lauren 474f25842a [compiler] Migrate CompilerError.invariant to new CompilerDiagnostic infra (#34403)
Mechanical PR to migrate existing invariants to use the new
CompilerDiagnostic infra @josephsavona added. Will tackle the others at
a later time.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34403).
* #34409
* #34404
* __->__ #34403
2025-09-06 12:58:08 -04:00
lauren 1fef581e1a [compiler] Deprecate CompilerErrorDetail (#34402)
Now that we have a new CompilerDiagnostic type (which the CompilerError
aggregate can hold), the old CompilerErrorDetail type can be marked as
deprecated. Eventually we should migrate everything to the new
CompilerDiagnostic type.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34402).
* #34409
* #34404
* #34403
* __->__ #34402
* #34401
2025-09-06 12:41:54 -04:00
lauren 60d9b9740d [compiler] Derive ErrorSeverity from ErrorCategory (#34401)
With #34176 we now have granular lint rules created for each compiler
ErrorCategory. However, we had remnants of our old error severities
still in use which makes reporting errors quite clunky. Previously you
would need to specify both a category and severity which often ended up
being the same.

This PR moves severity definition into our rules which are generated
from our categories. For now I decided to defer "upgrading" categories
from a simple string to a sum type since we are only using severities to
map errors to eslint severity.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34401).
* #34409
* #34404
* #34403
* #34402
* __->__ #34401
2025-09-06 12:41:29 -04:00
KimCookieYa c4e2508dad [react-devtools-shared] Fix URL construction when base URL is invalid (#34407)
### Problem
- Users encounter “Failed to construct 'URL': Invalid base URL” when
clicking the “View source” action in DevTools if the underlying base URL
is invalid.
- This exception originates from `new URL(relative, base)` and bubbles
up, interrupting the DevTools UI.
- Fixes GitHub issue
[#34317](https://github.com/facebook/react/issues/34317)

### Solution
- Wrap URL construction to:
  - First try `new URL(sourceMapAt, sourceURL)`.
  - If that fails, try `new URL(sourceMapAt)` as an absolute URL.
  - If both fail, return `null` (no symbolication) rather than throwing.
- This preserves normal behavior for valid bases and absolute URLs,
while avoiding crashes for invalid bases.

### Implementation details
- Updated `symbolicateSource` in
`packages/react-devtools-shared/src/symbolicateSource.js` to handle
invalid base URL scenarios without throwing.
- Added/verified tests in
`packages/react-devtools-shared/src/__tests__/utils-test.js`:
- “should not throw for invalid base URL with relative source map” →
resolves to `null`.
- “should resolve absolute source map even if base URL is invalid” →
still resolves correctly.

### Test plan
- Lint/format:
  - `yarn prettier-check`
  - `yarn linc`
- Type checking:
  - `yarn flow dom-node`
- Unit tests:
  - `yarn test --watchAll=false utils-test`
  - Optionally: `yarn test --watchAll=false utils-test inspectedElement`
- All of the above pass locally for experimental channel.

### Risks and rollout
- Risk: Low. Only affects cases where the base URL is invalid.
- Normal cases (valid base or absolute `sourceMappingURL`) are
unchanged.
- No user-facing API changes; DevTools UX becomes more resilient.

### Affected packages
- `react-devtools-shared`

### Related
- Fixes GitHub issue
[#34317](https://github.com/facebook/react/issues/34317)

### Checklist
- [x] Ran `yarn prettier-check`
- [x] Ran `yarn linc`
- [x] Ran `yarn flow dom-node`
- [x] Relevant unit tests passing
- [x] Linked issue and added a concise summary


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TestName` is helpful in development.
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## Summary

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does the pull request solve?
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## How did you test this change?

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2025-09-06 14:00:45 +01:00
Eugene Choi de5a1b203e [compiler][playground] (3/N) Config override panel (#34371)
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TestName` is helpful in development.
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6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
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-->

## Summary

Part 3 of adding a "Config Override" panel to the React compiler
playground. Added a button to apply config changes to the Input panel,
as well as making the tab collapsible. Added validation for the the
PluginOptions type (although comes with a bit more boilerplate) to make
it very obvious what the possible config errors could be. Added some
toasts for trying to apply broken configs.

<!--
Explain the **motivation** for making this change. What existing problem
does the pull request solve?
-->

## How did you test this change?


https://github.com/user-attachments/assets/63ab8636-396f-45ba-aaa5-4136e62ccccc


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2025-09-05 10:12:01 -04:00
Sebastian "Sebbie" Silbermann b9a045368b [DevTools] Allow inspecting root when navigating Suspense timeline (#34380) 2025-09-04 16:42:25 +02:00
Sebastian "Sebbie" Silbermann e2cc315a1b [DevTools] Don't suspend shell while retrieving original source for "open-in-editor" (#34381) 2025-09-04 16:39:07 +02:00
Sebastian "Sebbie" Silbermann 5a31758ed6 [DevTools] Allow inspection before streaming has finished in Chrome (#34360) 2025-09-04 12:21:06 +02:00
Sebastian "Sebbie" Silbermann ba6590dd7c [DevTools] Rerender boundaries when they unsuspend when advancing the timeline (#34359) 2025-09-04 10:49:16 +02:00
Joseph Savona 2710795a1e [compiler] Cleanup for @enablePreserveExistingMemoizationGuarantees (#34346)
I tried turning on `@enablePreserveExistingMemoizationGuarantees` by
default and cleaned up a couple small things:

* We emit freeze calls for StartMemoize deps but these had
ValueReason.Other so the message wasn't great. We now treat these like
other hook arguments.
* PruneNonEscapingScopes was being too aggressive in this mode and
memoizing even loads of globals. Switching to
MemoizationLevel.Conditional ensures we build a graph that connects
through to primitive-returning function calls, but doesn't unnecessarily
force memoization otherwise.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34346).
* #34347
* __->__ #34346
2025-09-03 21:30:52 -07:00
Joseph Savona 735e9ac54e [compiler] enablePreserveExistingMemo memoizes primitive-returning functions (#34343)
`@enablePreserveExistingMemoizationGuarantees` mode currently does not
guarantee memoization of primitive-returning functions. We're often able
to infer that a function returns a primitive based on how its result is
used, for example `foo() + 1` or `object[getIndex()]`, and by default we
do not currently memoize computation that produces a primitive. The
reasoning behind this is that the compiler is primarily focused on
stopping cascading updates — it's fine to recompute a primitive since we
can cheaply compare that primitive and avoid unnecessary downstream
recomputation. But we've gotten a lot of feedback that people find this
surprising, and that sometimes the computation can be expensive enough
that it should be memoized.

This PR changes `@enablePreserveExistingMemoizationGuarantees` mode to
ensure that primitive-returning functions get memoized. Other modes will
not memoize these functions. Separately from this we are considering
enabling this mode by default.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34343).
* #34347
* #34346
* __->__ #34343
* #34335
2025-09-03 17:45:17 -07:00