This converts some of our test suite to use the `waitFor` test pattern,
instead of the `expect(Scheduler).toFlushAndYield` pattern. Most of
these changes are automated with jscodeshift, with some slight manual
cleanup in certain cases.
See #26285 for full context.
There is a problem with <style> as resource. For css-in-js libs there
may be an very large number of these hoistables being created. The
number of style tags can grow quickly and to help reduce the prevalence
of this FIzz now aggregates all style tags for a given precedence into a
single tag. The client can 'hydrate' against these compound tags but
currently on the client insertions are done individually.
additionally drops the implementation where style tags are embedding in
a template for one where `media="not all"` is set. The idea is to have
the browser construct the underlying stylesheet eagerly which does not
happen if the tag is embedded in a template
Key Decision:
One choice made in this PR is that we flush style tags eagerly even if a
boundary is blocked that is the only thing that depends on that style
rule. The reason we are starting with this implementation is that it
allows a very condensed representation of the style resources. If we
tracked which rules were used in which boundaries we would need a style
resource for every rendered <style> tag. This could be problematic for
css-in-js libs that might render hundreds or thousands of style tags.
The tradeoff here is we slightly delay content reveal in some cases (we
send extra bytes) but we have fewer DOM tags and faster SSR runtime
The codemod I used in #26288 accidentally caused some comments to be
deleted. Because not all affected lines included comments, I didn't
notice until after landing.
This adds the comments back.
## Summary
When looking into the compiled code of `installHook.js` of the extension
build, I noticed that it actually includes the large `attach` function
(from renderer.js). I don't think it was expected.
This is because `hook.js` imports from `backend/console.js` which
imports from `backend/renderer.js` for `getInternalReactConstants`
A straightforward way is to extract function
`getInternalReactConstants`. However, I think it's more simplified to
just merge these two files and save the 361K renderer.js from the
extension build since we have always been loading this code anyways.
I changed the execution check from `__REACT_DEVTOOLS_ATTACH__ ` to the
session storage.
## How did you test this change?
Everything works normal in my local build.
## Summary
A few methods in `ReactFiberReconciler` are supposed to return
`PublicInstance` values, but they return the `stateNode` from the fiber
directly. This assumes that the `stateNode` always matches the public
instance (which it does on Web) but that's not the case in React Native,
where the public instance is a field in that object.
This hasn't caused issues because everywhere where we use that method in
React Native we actually extract the real public instance from this
"fake" public instance.
This PR fixes the inconsistency and cleans up some code.
## How did you test this change?
Existing tests.
This converts some of our test suite to use the `waitFor` test pattern,
instead of the `expect(Scheduler).toFlushAndYield` pattern. Most of
these changes are automated with jscodeshift, with some slight manual
cleanup in certain cases.
See #26285 for full context.
Over the years, we've gradually aligned on a set of best practices for
for testing concurrent React features in this repo. The default in most
cases is to use `act`, the same as you would do when testing a real
React app. However, because we're testing React itself, as opposed to an
app that uses React, our internal tests sometimes need to make
assertions on intermediate states that `act` intentionally disallows.
For those cases, we built a custom set of Jest assertion matchers that
provide greater control over the concurrent work queue. It works by
mocking the Scheduler package. (When we eventually migrate to using
native postTask, it would probably work by stubbing that instead.)
A problem with these helpers that we recently discovered is, because
they are synchronous function calls, they aren't sufficient if the work
you need to flush is scheduled in a microtask — we don't control the
microtask queue, and can't mock it.
`act` addresses this problem by encouraging you to await the result of
the `act` call. (It's not currently required to await, but in future
versions of React it likely will be.) It will then continue flushing
work until both the microtask queue and the Scheduler queue is
exhausted.
We can follow a similar strategy for our custom test helpers, by
replacing the current set of synchronous helpers with a corresponding
set of async ones:
- `expect(Scheduler).toFlushAndYield(log)` -> `await waitForAll(log)`
- `expect(Scheduler).toFlushAndYieldThrough(log)` -> `await
waitFor(log)`
- `expect(Scheduler).toFlushUntilNextPaint(log)` -> `await
waitForPaint(log)`
These APIs are inspired by the existing best practice for writing e2e
React tests. Rather than mock all task queues, in an e2e test you set up
a timer loop and wait for the UI to match an expecte condition. Although
we are mocking _some_ of the task queues in our tests, the general
principle still holds: it makes it less likely that our tests will
diverge from real world behavior in an actual browser.
In this commit, I've implemented the new testing helpers and converted
one of the Suspense tests to use them. In subsequent steps, I'll codemod
the rest of our test suite.
## Summary
I'm going to start implementing parts of this proposal
https://github.com/react-native-community/discussions-and-proposals/pull/607
As part of that implementation I'm going to refactor a few parts of the
interface between React and React Native. One of the main problems we
have right now is that we have private parts used by React and React
Native in the public instance exported by refs. I want to properly
separate that.
I saw that a few methods to attach event handlers imperatively on refs
were also exposing some things in the public instance (the
`_eventListeners`). I checked and these methods are unused, so we can
just clean them up instead of having to refactor them too. Adding
support for imperative event listeners is in the roadmap after this
proposal, and its implementation might differ after this refactor.
This is essentially a manual revert of #23386.
I'll submit more PRs after this for the rest of the refactor.
## How did you test this change?
Existing jest tests. Will test a React sync internally at Meta.
Selective hydration is implemented by suspending the current render
using a special internal opaque object. This is conceptually similar to
suspending with a thenable in userspace, but the opaque object should
not leak outside of the reconciler.
We were accidentally passing this object to DevTool's
markComponentSuspended function, which expects an actual thenable. This
happens in the error handling path (handleThrow).
The fix is to check for the exception reason before calling
markComponentSuspended. There was already a naive check in place, but it
didn't account for all possible enum values of the exception reason.
Builds on #26257.
To do this we need access to a manifest for which scripts and CSS are
used for each "page" (entrypoint).
The initial script to bootstrap the app is inserted with
`bootstrapScripts`. Subsequent content are loaded using the chunks
mechanism built-in.
The stylesheets for each pages are prepended to each RSC payload and
rendered using Float. This doesn't yet support styles imported in
components that are also SSR:ed nor imported through Server Components.
That's more complex and not implemented in the node loader.
HMR doesn't work after reloads right now because the SSR renderer isn't
hot reloaded because there's no idiomatic way to hot reload ESM modules
in Node.js yet. Without killing the HMR server. This leads to hydration
mismatches when reloading the page after a hot reload.
Notably this doesn't show serializing the stream through the HTML like
real implementations do. This will lead to possible hydration mismatches
based on the data. However, manually serializing the stream as a string
isn't exactly correct due to binary data. It's not the idiomatic way
this is supposed to work. This will all be built-in which will make this
automatic in the future.
This proxies requests through the global server instead of requesting
RSC responses from the regional server. This is a bit closer to
idiomatic, and closer to SSR.
This also wires up HMR using the Middleware technique instead of server.
This will be an important part of RSC compatibility because there will
be a `react-refresh` aspect to the integration.
This convention uses `Accept` header to branch a URL between HTML/RSC
but it could be anything really. Special headers, URLs etc. We might be
more opinionated about this in the future but now it's up to the router.
Some fixes for Node 16/17 support in the loader and fetch polyfill.
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## Summary
Adding `preconnect` and `prefetchDNS` to rendering-stub build
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preloads often need to come with a type attribute which allows browsers
to decide if they support the preloading resource's type. If the type is
unsupported the preload will not be fetched by the Browser. This change
adds support for `type` in `ReactDOM.preload()` as a string option.
Adds two new ReactDOM methods
### `ReactDOM.prefetchDNS(href: string)`
In SSR this method will cause a `<link rel="dns-prefetch" href="..." />`
to flush before most other content both on intial flush (Shell) and late
flushes. It will only emit one link per href.
On the client, this method will case the same kind of link to be
inserted into the document immediately (when called during render, not
during commit) if there is not already a matching element in the
document.
### `ReactDOM.preconnect(href: string, options?: { crossOrigin?: string
})`
In SSR this method will cause a `<link rel="dns-prefetch" href="..."
[corssorigin="..."] />` to flush before most other content both on
intial flush (Shell) and late flushes. It will only emit one link per
href + crossorigin combo.
On the client, this method will case the same kind of link to be
inserted into the document immediately (when called during render, not
during commit) if there is not already a matching element in the
document.
Fixes https://github.com/facebook/react/issues/25924 for React DevTools
specifically.
## Summary
If we remove the script after it's loaded, it creates a race condition
with other code. If some other code is searching for the first script
tag or first element of the document, this might broke it.
## How did you test this change?
I've tested in my local build that even if we remove the script tag
immediately, the code is still correctly executed.
When resuming a suspended render, there may be more Hooks to be called
that weren't seen the previous time through. Make sure to switch to the
mount dispatcher when calling use() if the next Hook call should be
treated as a mount.
Fixes#25964.
We encode strings 2048 UTF-8 bytes at a time. If the string we are
encoding crosses to the next chunk but the current chunk doesn't fit an
integral number of characters, we need to make sure not to send the
whole buffer, only the bytes that are actually meaningful.
Fixes#24985. I was able to verify that this fixes the repro shared in
the issue (be careful when testing because the null bytes do not show
when printed to my terminal, at least). However, I don't see a clear way
to add a test for this that will be resilient to small changes in how we
encode the markup (since it depends on where specific multibyte
characters fall against the 2048-byte boundaries).
## Summary
We had this as a temporary fix for #24626. Now that Chrome team decides
to turn the flag on again (with good reasons explained in
https://bugs.chromium.org/p/chromium/issues/detail?id=1241986#c31), we
will turn it into a long term solution.
In the future, we want to explore whether we can render React elements
on panel.html instead, as `requestAnimationFrame` produces higher
quality animation.
## How did you test this change?
Tested on local build with "Throttle non-visible cross-origin iframes"
flag enabled.
`eventTime` is a vestigial field that can be cleaned up. It was
originally used as part of the starvation mechanism but it's since been
replaced by a per-lane field on the root.
This is a part of a series of smaller refactors I'm doing to
simplify/speed up the `setState` path, related to the Sync Unification
project that @tyao1 has been working on.
This splits out the Edge and Node implementations of Flight Client into
their own implementations. The Node implementation now takes a Node
Stream as input.
I removed the bundler config from the Browser variant because you're
never supposed to use that in the browser since it's only for SSR.
Similarly, it's required on the server. This also enables generating a
SSR manifest from the Webpack plugin. This is necessary for SSR so that
you can reverse look up what a client module is called on the server.
I also removed the option to pass a callServer from the server. We might
want to add it back in the future but basically, we don't recommend
calling Server Functions from render for initial render because if that
happened client-side it would be a client-side waterfall. If it's never
called in initial render, then it also shouldn't ever happen during SSR.
This might be considered too restrictive.
~This also compiles the unbundled packages as ESM. This isn't strictly
necessary because we only need access to dynamic import to load the
modules but we don't have any other build options that leave
`import(...)` intact, and seems appropriate that this would also be an
ESM module.~ Went with `import(...)` in CJS instead.
> All notifications of mutations that have already been detected, but
not yet reported to the observer, are discarded. To hold on to and
handle the detected but unreported mutations, use the takeRecords()
method.
> -- ([Mozilla docs for disconnect](
https://developer.mozilla.org/en-US/docs/Web/API/MutationObserver/disconnect))
Fizz external runtime needs to process mutation records (representing
potential Fizz instructions) before calling `disconnect()`. We currently
do not do this (and might drop some instructions).
We should never use any logic beyond declarations in the module scope,
including conditions, because in a cycle that can lead to problems.
More importantly, the compiler can't safely reorder statements between
these points which limits the optimizations we can do.
We currently have an awkward set up because the server can be used in
two ways. Either you can have the server code prebundled using Webpack
(what Next.js does in practice) or you can use an unbundled Node.js
server (what the reference implementation does).
The `/client` part of RSC is actually also available on the server when
it's used as a consumer for SSR. This should also be specialized
depending on if that server is Node or Edge and if it's bundled or
unbundled.
Currently we still assume Edge will always be bundled since we don't
have an interceptor for modules there.
I don't think we'll want to support this many combinations of setups for
every bundler but this might be ok for the reference implementation.
This PR doesn't actually change anything yet. It just updates the
plumbing and the entry points that are built and exposed. In follow ups
I'll fork the implementation and add more features.
---------
Co-authored-by: dan <dan.abramov@me.com>
## Summary
CSS has a new property called `scale` (`scale: 2` is a shorthand for
`transform: scale(2)`).
In vanilla JavaScript, we can do the following:
```js
document.querySelector('div').scale = 2;
```
which will make the `<div>` twice as big. So in JavaScript, it is
possible to pass a plain number.
However, in React, the following does not work currently:
```js
<div style={{scale: 2}}>
```
because `scale` is not in the list of unitless properties. This PR adds
`scale` to the list.
## How did you test this change?
I built `react` and `react-dom` from source and copied it into the
node_modules of my project and verified that now `<div style={{scale:
2}}>` does indeed work whereas before it did not.
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## Summary
This TODO mentions an issue with JSDOM that [seems to have been
resolved](https://github.com/jsdom/jsdom/pull/2996).
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## How did you test this change?
- Ensured that the `document.activeElement` is no longer `node` after
`node.blur` is called.
- Verified that the tests still pass.
- Looked for [a merged PR that fixes the
issue](https://github.com/jsdom/jsdom/pull/2996).
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## Summary
Fixes "ReferenceError: You are trying to access a property or method of
the Jest environment after it has been torn down." in
`ReactIncrementalErrorHandling-test.internal.js`
Alternatives:
1. Additional `await act(cb)` call where `cb` makes sure we can flush
until next paint without throwing
```js
// Ensure test isn't exited with pending work
await act(async () => {
root.render(<App shouldThrow={false} />);
});
```
1. Use `toFlushAndThrow`
```diff
- let error;
- try {
- await act(async () => {
- root.render(<App shouldThrow={true} />);
- });
- } catch (e) {
- error = e;
- }
+ root.render(<App shouldThrow={true} />);
- expect(error.message).toBe('Oops!');
+ expect(Scheduler).toFlushAndThrow('Oops!');
expect(numberOfThrows < 100).toBe(true);
```
But then it still wouldn't make sense to pass `resolve` and `reject` to
the next `flushActWork`. Even if the next `flushActWork` would flush
until next paint without throwing, we couldn't resolve or reject because
we already did reject.
## How did you test this change?
- `yarn test --watch
packages/react-reconciler/src/__tests__/ReactIncrementalErrorHandling-test.internal.js`
produces no more errors after the test finishes.
I forgot to guard the `getRootNode` call in #26106 and it fails in IE8
and old jsdom. I consolidated the implementation a bit and removed the
unguarded call
When we have a key we read displayName eagerly for future warnings.
In general, React should be inspecting if something is a client
reference before dotting into it. However, we use displayName a lot and
it kind of has defined meaning for debugging everywhere it's used so
seems fine to treat this as undefined.
## Hoistables
In the original implementation of Float, all hoisted elements were
treated like Resources. They had deduplication semantics and hydrated
based on a key. This made certain kinds of hoists very challenging such
as sequences of meta tags for `og:image:...` metadata. The reason is
each tag along is not dedupable based on only it's intrinsic properties.
two identical tags may need to be included and hoisted together with
preceding meta tags that describe a semantic object with a linear set of
html nodes.
It was clear that the concept of Browser Resources (stylesheets /
scripts / preloads) did not extend universally to all hositable tags
(title, meta, other links, etc...)
Additionally while Resources benefit from deduping they suffer an
inability to update because while we may have multiple rendered elements
that refer to a single Resource it isn't unambiguous which element owns
the props on the underlying resource. We could try merging props, but
that is still really hard to reason about for authors. Instead we
restrict Resource semantics to freezing the props at the time the
Resource is first constructed and warn if you attempt to render the same
Resource with different props via another rendered element or by
updating an existing element for that Resource.
This lack of updating restriction is however way more extreme than
necessary for instances that get hoisted but otherwise do not dedupe;
where there is a well defined DOM instance for each rendered element. We
should be able to update props on these instances.
Hoistable is a generalization of what Float tries to model for hoisting.
Instead of assuming every hoistable element is a Resource we now have
two distinct categories, hoistable elements and hoistable resources. As
one might guess the former has semantics that match regular Host
Components except the placement of the node is usually in the <head>.
The latter continues to behave how the original implementation of
HostResource behaved with the first iteration of Float
### Hoistable Element
On the server hoistable elements render just like regular tags except
the output is stored in special queues that can be emitted in the stream
earlier than they otherwise would be if rendered in place. This also
allow for instance the ability to render a hoistable before even
rendering the <html> tag because the queues for hoistable elements won't
flush until after we have flushed the preamble (`<DOCTYPE
html><html><head>`).
On the client, hoistable elements largely operate like HostComponents.
The most notable difference is in the hydration strategy. If we are
hydrating and encounter a hoistable element we will look for all tags in
the document that could potentially be a match and we check whether the
attributes match the props for this particular instance. We also do this
in the commit phase rather than the render phase. The reason hydration
can be done for HostComponents in render is the instance will be removed
from the document if hydration fails so mutating it in render is safe.
For hoistables the nodes are not in a hydration boundary (Root or
SuspenseBoundary at time of writing) and thus if hydration fails and we
may have an instance marked as bound to some Fiber when that Fiber never
commits. Moving the hydration matching to commit ensures we will always
succeed in pairing the hoisted DOM instance with a Fiber that has
committed.
### Hoistable Resource
On the server and client the semantics of Resources are largely the same
they just don't apply to title, meta, and most link tags anymore.
Resources hoist and dedupe via an `href` key and are ref counted. In a
future update we will add a garbage collector so we can clean up
Resources that no longer have any references
## `<style>` support
In earlier implementations there was no support for <style> tags. This
PR adds support for treating `<style href="..."
precedence="...">...</style>` as a Resource analagous to `<link
rel="stylesheet" href="..." precedence="..." />`
It may seem odd at first to require an href to get Resource semantics
for a style tag. The rationale is that these are for inlining of actual
external stylesheets as an optimization and for URI like scoping of
inline styles for css-in-js libraries. The href indicates that the key
space for `<style>` and `<link rel="stylesheet" />` Resources is shared.
and the precedence is there to allow for interleaving of both kinds of
Style resources. This is an advanced feature that we do not expect most
app developers to use directly but will be quite handy for various
styling libraries and for folks who want to inline as much as possible
once Fizz supports this feature.
## refactor notes
* HostResource Fiber type is renamed HostHoistable to reflect the
generalization of the concept
* The Resource object representation is modified to reduce hidden class
checks and to use less memory overall
* The thing that distinguishes a resource from an element is whether the
Fiber has a memoizedState. If it does, it will use resource semantics,
otherwise element semantics
* The time complexity of matching hositable elements for hydration
should be improved
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.
We're fixing the timing of layout and passive effects in React Native,
and adding support for some Web APIs so common use cases for those
effects can be implemented with the same code on React and React Native.
Let's take this example:
```javascript
function MyComponent(props) {
const viewRef = useRef();
useLayoutEffect(() => {
const rect = viewRef.current?.getBoundingClientRect();
console.log('My view is located at', rect?.toJSON());
}, []);
return <View ref={viewRef}>{props.children}</View>;
}
```
This could would work as expected on Web (ignoring the use of `View` and
assuming something like `div`) but not on React Native because:
1. Layout is done asynchronously in a background thread in parallel with
the execution of layout and passive effects. This is incorrect and it's
being fixed in React Native (see
https://github.com/facebook/react-native/commit/afec07aca273503b0647dbf1f73c518c6e52e8ba).
2. We don't have an API to access layout information synchronously. The
existing `ref.current.measureInWindow` uses callbacks to pass the
result. That is asynchronous at the moment in Paper (the legacy renderer
in React Native), but it's actually synchronous in Fabric (the new React
Native renderer).
This fixes point 2) by adding a Web-compatible method to access layout
information (on Fabric only).
This has 2 dependencies in React Native:
1. Access to `getBoundingClientRect` in Fabric, which was added in
https://github.com/facebook/react-native/blob/main/ReactCommon/react/renderer/uimanager/UIManagerBinding.cpp#L644-
L676
2. Access to `DOMRect`, which was added in
https://github.com/facebook/react-native/commit/673c7617bcf90a892a0afc2c0d9cf9c0493fdf27
.
As next step, I'll modify the implementation of this and other methods
in Fabric to warn when they're accessed during render. We can't do this
on Web because we can't (shouldn't) modify built-in DOM APIs, but we can
do it in React Native because the refs objects are built by the
framework.
## Summary
- yarn.lock diff +-6249, **small pr**
- use jest-environment-jsdom by default
- uncaught error from jsdom is an error object instead of strings
- abortSignal.reason is read-only in jsdom and node,
https://developer.mozilla.org/en-US/docs/Web/API/AbortSignal/reason
## How did you test this change?
ci green
---------
Co-authored-by: Sebastian Silbermann <silbermann.sebastian@gmail.com>
## Summary
Prefer `getChildrenAsJSX` or `toMatchRenderedOutput` over `getChildren`.
Use `dangerouslyGetChildren` if you really need to (e.g. for `toBe`
assertions).
Prefer `getPendingChildrenAsJSX` over `getPendingChildren`. Use
`dangerouslyGetPendingChildren` if you really need to (e.g. for `toBe`
assertions).
`ReactNoop.getChildren` contains the fibers as non-enumerable
properties. If you pass the children to `toEqual` and have a mismatch,
Jest performance is very poor (to the point of causing out-of-memory
crashes e.g.
https://app.circleci.com/pipelines/github/facebook/react/38084/workflows/02ca0cbb-bab4-4c19-8d7d-ada814eeebb9/jobs/624297/parallel-runs/5?filterBy=ALL&invite=true#step-106-27).
Mismatches can sometimes be intended e.g. on gated tests.
Instead, I converted almost all of the `toEqual` assertions to
`toMatchRenderedOutput` assertions or compare the JSX instead. For
ReactNoopPersistent we still use `getChildren` since we have assertions
on referential equality. `toMatchRenderedOutput` is more accurate in
some instances anyway. I highlighted some of those more accurate
assertions in review-comments.
## How did you test this change?
- [x] `CIRCLE_NODE_TOTAL=20 CIRCLE_NODE_INDEX=5 yarn test
-r=experimental --env=development --ci`: Can take up to 350s (and use up
to 7GB of memory) on `main` but 11s on this branch
- [x] No more slow `yarn test` parallel runs of `yarn_test` jobs (the
steps in these runs should take <1min but sometimes they take 3min and
end with OOM like
https://app.circleci.com/pipelines/github/facebook/react/38084/workflows/02ca0cbb-bab4-4c19-8d7d-ada814eeebb9/jobs/624258/parallel-runs/5?filterBy=ALL:
Looks good with a sample size of 1
https://app.circleci.com/pipelines/github/facebook/react/38110/workflows/745109a2-b86b-429f-8c01-9b23a245417a/jobs/624651
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## Summary
This PR:
- Replaces the existing usages of methods from the `semver` library in
the React DevTools source with an inlined version based on
https://www.npmjs.com/package/semver-compare.
This appears to drop the unminified bundle sizes of 3 separate
`react-devtools-extensions` build artifacts by about 50K:

## How did you test this change?
I was originally working on [a fork of React
DevTools](https://github.com/replayio/react/pull/2) for use with
https://replay.io , specifically our integration of the React DevTools
UI to show the React component tree while users are debugging a recorded
application.
As part of the dev work on that fork, I wanted to shrink the bundle size
of the extension's generated JS build artifacts. I noted that the
official NPM `semver` library was taking up a noticeable chunk of space
in the bundles, and saw that it's only being used in a handful of places
to do some very simple version string comparisons.
I was able to replace the `semver` imports and usages with a simple
alternate comparison function, and confirmed via hands-on checks and
console logging that the checks behaved the same way.
Given that, I wanted to upstream this particular change to help shrink
the real extension's bundle sizes.
I know that it's an extension, so bundle size isn't _as_ critical a
concern as it would be for a pure library. But, smaller download sizes
do benefit all users, and that also includes sites like CodeSandbox and
Replay that are using the React DevTools as a library as well.
I'm happy to tweak this PR if necessary. Thanks!
as reported in #26128 `ReactDOM.render(..., document)` crashed when
`enableHostSingletons` was on. This is because it had a different way of
clearing the container than `createRoot(document)`. I updated the legacy
implementation to share the clearing behavior of `creatRoot` which will
preserve the singleton instances.
I also removed the warning saying not to use `document.body` as a
container
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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
supports the same options as `yarn test`.
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`chrome://inspect`, and press "Inspect".
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## Summary
<!--
Explain the **motivation** for making this change. What existing problem
does the pull request solve?
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This pull request emit the trace update events `drawTraceUpdates` with
the trace frame information when the trace update drawer runs outside of
web environment. This allows React Devtool running in mobile or other
platforms have a chance to render such highlights and provide similar
feature on web to provide re-render highlights. This is a feature needed
for identifying unnecessary re-renders.
## How did you test this change?
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I tested this change with Flipper desktop app running against mobile
app, and verified that the event with correct array of frames are
passing through properly.
We currently abuse the browser builds for Web streams derived
environments. We already have a special build for Bun but we should also
have one for [other "edge"
runtimes](https://runtime-keys.proposal.wintercg.org/) so that we can
maximally take advantage of the APIs that exist on each platform.
In practice, we currently check for a global property called
`AsyncLocalStorage` in the server browser builds which we shouldn't
really do since browsers likely won't ever have it. Additionally, this
should probably move to an import which we can't add to actual browser
builds where that will be an invalid import. So it has to be a separate
build. That's not done yet in this PR but Vercel will follow
Cloudflare's lead here.
The `deno` key still points to the browser build since there's no
AsyncLocalStorage there but it could use this same or a custom build if
support is added.