This PR reorganizes the `react-dom` entrypoint to only pull in code that
is environment agnostic. Previously if you required anything from this
entrypoint in any environment the entire client reconciler was loaded.
In a prior release we added a server rendering stub which you could
alias in server environments to omit this unecessary code. After landing
this change this entrypoint should not load any environment specific
code.
While a few APIs are truly client (browser) only such as createRoot and
hydrateRoot many of the APIs you import from this package are only
useful in the browser but could concievably be imported in shared code
(components running in Fizz or shared components as part of an RSC app).
To avoid making these require opting into the client bundle we are
keeping them in the `react-dom` entrypoint and changing their
implementation so that in environments where they are not particularly
useful they do something benign and expected.
#### Removed APIs
The following APIs are being removed in the next major. Largely they
have all been deprecated already and are part of legacy rendering modes
where concurrent features of React are not available
* `render`
* `hydrate`
* `findDOMNode`
* `unmountComponentAtNode`
* `unstable_createEventHandle`
* `unstable_renderSubtreeIntoContainer`
* `unstable_runWithPrioirty`
#### moved Client APIs
These APIs were available on both `react-dom` (with a warning) and
`react-dom/client`. After this change they are only available on
`react-dom/client`
* `createRoot`
* `hydrateRoot`
#### retained APIs
These APIs still exist on the `react-dom` entrypoint but have normalized
behavior depending on which renderers are currently in scope
* `flushSync`: will execute the function (if provided) inside the
flushSync implemention of FlightServer, Fizz, and Fiber DOM renderers.
* `unstable_batchedUpdates`: This is a noop in concurrent mode because
it is now the only supported behavior because there is no legacy
rendering mode
* `createPortal`: This just produces an object. It can be called from
anywhere but since you will probably not have a handle on a DOM node to
pass to it it will likely warn in environments other than the browser
* preloading APIS such as `preload`: These methods will execute the
preload across all renderers currently in scope. Since we resolve the
Request object on the server using AsyncLocalStorage or the current
function stack in practice only one renderer should act upon the
preload.
In addition to these changes the server rendering stub now just rexports
everything from `react-dom`. In a future minor we will add a warning
when using the stub and in the next major we will remove the stub
altogether
Only the FB entry point has legacy mode now so we can move the remaining
code in there.
Also enable disableLegacyMode in modern www builds since it doesn't
expose those entry points.
Now dependent on #28709.
---------
Co-authored-by: Josh Story <story@hey.com>
## Summary
- Updated `webpack` (and all related packages) to v5 in
`react-devtools-*` packages.
- I haven't touched any `TODO (Webpack 5)`. Tried to poke it, but each
my attempt failed and parsing hook names feature stopped working. I will
work on this in a separate PR.
- This work is one of prerequisites for updating Firefox extension to
manifests v3
related PRs:
https://github.com/facebook/react/pull/22267https://github.com/facebook/react/pull/26506
## How did you test this change?
Tested on all surfaces, explicitly checked that parsing hook names
feature still works.
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
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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!
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
## Summary
This PR adds a "perf regression tests" page to react-devtools-shell.
This page is meant to be used as a performance sanity check we will run
whenever we release a new version or finish a major refactor.
Similar to other pages in the shell, this page can load the inline
version of devtools and a test react app on the same page. But this page
does not load devtools automatically like other pages. Instead, it
provides a button that allows us to load devtools on-demand, so that we
can easily compare perf numbers without devtools against the numbers
with devtools.
<img width="561" alt="image"
src="https://user-images.githubusercontent.com/1001890/184059633-e4f0852c-8464-4d94-8064-1684eee626f4.png">
As a first step, this page currently only contain one test:
mount/unmount a large subtree. This is to catch perf issues that
devtools can cause on the react applications it's running on, which was
once a bug fixed in #24863.
In the future, we plan to add:
- more test apps covering different scenarios
- perf numbers within devtools (e.g. initial load)
## How did you test this change?
In order to show this test app can actually catch the perf regression
it's aiming at, I reverted #24863 locally. Here is the result:
https://user-images.githubusercontent.com/1001890/184059214-9c9b308c-173b-4dd7-b815-46fbd7067073.mov
As shown in the video, the time it takes to unmount the large subtree
significantly increased after DevTools is loaded.
For comparison, here is how it looks like before the fix was reverted:
<img width="452" alt="image"
src="https://user-images.githubusercontent.com/1001890/184059743-0968bc7d-4ce4-42cd-b04a-f6cbc078d4f4.png">
## about the `requestAnimationFrame` method
For this test, I used `requestAnimationFrame` to catch the time when
render and commit are done. It aligns very well with the numbers
reported by Chrome DevTools performance profiling. For example, in one
run, the numbers reported by my method are
<img width="464" alt="image"
src="https://user-images.githubusercontent.com/1001890/184060228-990a4c75-f594-411a-9f85-fa5532ec8c37.png">
They are very close to the numbers reported by Chrome profiling:
<img width="456" alt="image"
src="https://user-images.githubusercontent.com/1001890/184060355-a15d1ec5-c296-4016-9c83-03e761f387e3.png">
<img width="354" alt="image"
src="https://user-images.githubusercontent.com/1001890/184060375-19029010-3aed-4a23-890e-397cdba86d9e.png">
`<Profiler>` is not able to catch this issue here.
If you are aware of a better way to do this, please kindly share with
me.
Made a couple of fixes to the `devtools-test-shell`
* test selectors aren't available in > React v18.0 either, so we'll need to mock the test selector functions there as well
* `react-dom/client` should map to `react-dom/client` and not `react-dom`
This PR adds an e2e regression app to the react-devtools-shell package. This app:
* Has an app.js and an appLegacy.js entrypoint because apps prior to React 18 need to use ReactDOM.render. These files will create and render multiple test apps (though they currently only render the List)
* Moved the ListApp out of the e2e folder and into an e2e-apps folder so that both e2e and e2e-regression can use the same test apps
* Creates a ListAppLegacy app because prior to React 16.8 hooks didn't exist.
* Added a devtools file for the e2e-regression
* Modifies the webpack config so that the e2e-regression React app can use different a different React version than DevTools