Flow 0.280 introduced stricter type checking for `incompatible-type` errors,
requiring additional $FlowFixMe suppressions alongside existing ones. Changes:
- Made `QueuingStrategy` properties optional in streams.js
- Made all properties optional in Web Animations API types (EffectTiming,
KeyframeAnimationOptions, etc.)
- Added `$FlowFixMe[incompatible-type]` alongside existing suppressions in
multiple files where Flow now reports additional type mismatches
The `useOpenResource` hook is now used to open links. Currently, the
`<>` icon for the component stacks and the link in the bottom of the
components stack. But it'll also be used for many new links like stacks.
If this new option is configured, and this is a local file then this is
opened directly in the external editor. Otherwise it fallbacks to open
in the Sources tab or whatever the standalone or inline is configured to
use.
<img width="453" height="252" alt="Screenshot 2025-07-24 at 4 09 09 PM"
src="https://github.com/user-attachments/assets/04cae170-dd30-4485-a9ee-e8fe1612978e"
/>
I prominently surface this option in the Source pane to make it
discoverable.
<img width="588" height="144" alt="Screenshot 2025-07-24 at 4 03 48 PM"
src="https://github.com/user-attachments/assets/0f3a7da9-2fae-4b5b-90ec-769c5a9c5361"
/>
When this is configured, the "Open in Editor" is hidden since that's
just the default. I plan on deprecating this button to avoid having the
two buttons going forward.
Notably there's one exception where this doesn't work. When you click an
Action or Event listener it takes you to the Sources tab and you have to
open in editor from there. That's because we use the `inspect()`
mechanism instead of extracting the source location. That's because we
can't do the "throw trick" since these can have side-effects. The Chrome
debugger protocol would solve this but it pops up an annoying dialog. We
could maybe only attach the debugger only for that case. Especially if
the dialog disappears before you focus on the browser again.
In RSC and other stacks now we use a lot of `ReactFunctionLocation` type
to represent the location of a function. I.e. the location of the
beginning of the function (the enclosing line/col) that is represented
by the "Source" of the function. This is also what the parent Component
Stacks represents.
As opposed to `ReactCallSite` which is what normal stack traces and
owner stacks represent. I.e. the line/column number of the callsite into
the next function.
We can start sharing more code by using the `ReactFunctionLocation` type
to represent the component source location and it also helps clarify
which ones are function locations and which ones are callsites as we
start adding more stack traces (e.g. for async debug info and owner
stack traces).
Fixes https://github.com/facebook/react/issues/31100.
There are 2 things:
1. In https://github.com/facebook/react/pull/30987, we've introduced a
breaking change: importing `react-devtools-core` is no longer enough for
installing React DevTools global Hook. You need to call `initialize`, in
which you may provide initial settings. I am not adding settings here,
because it is not implemented, and there are no plans for supporting
this.
2. Calling `installHook` is not necessary inside `standalone.js`,
because this script is running inside Electron wrapper (which is just a
UI, not the app that we are debugging). We will loose the ability to use
React DevTools on this React application, but I guess thats fine.
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## Summary
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does the pull request solve?
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When debugging applications that are experiencing runaway re-rendering,
it is helpful to profile them in the React Developer Tools.
Unfortunately there is a size limit on the captured profile which can
make them impossible to inspect or save. The limitations I have found
are in `postMessage` for the Chrome extension and in the `ws` websocket
server for the standalone app.
Profiling an app that produces a large profile artifact will simply show
that no profiling data was captured and output an error in the console,
here shown for the standalone app:
```text
standalone.js:92 [React DevTools] Error with websocket connection i {target: H, type: 'error', message: 'Max payload size exceeded', error: RangeError: Max payload size exceeded
at e.exports.haveLength (/Users/rune/.npm/_npx/8ea6ac5c50…}error: RangeError: Max payload size exceeded
```
This change simply increases the max payload of the websocket server in
the standalone app so that larger profiles may be captured and
inspected.
## How did you test this change?
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I verified that I could capture and inspect profiling data that
previously exceeded the default limitation for a particular app
Stacked on https://github.com/facebook/react/pull/28351, please review
only the last commit.
Top-level description of the approach:
1. Once user selects an element from the tree, frontend asks backend to
return the inspected element, this is where we simulate an error
happening in `render` function of the component and then we parse the
error stack. As an improvement, we should probably migrate from custom
implementation of error stack parser to `error-stack-parser` from npm.
2. When frontend receives the inspected element and this object is being
propagated, we create a Promise for symbolicated source, which is then
passed down to all components, which are using `source`.
3. These components use `use` hook for this promise and are wrapped in
Suspense.
Caching:
1. For browser extension, we cache Promises based on requested resource
+ key + column, also added use of
`chrome.devtools.inspectedWindow.getResource` API.
2. For standalone case (RN), we cache based on requested resource url,
we cache the content of it.
`_debugSource` was removed in
https://github.com/facebook/react/pull/28265.
This PR migrates DevTools to define `source` for Fiber based on
component stacks. This will be done lazily for inspected elements, once
user clicks on the element in the tree.
`DevToolsComponentStackFrame.js` was just copy-pasted from the
implementation in `ReactComponentStackFrame`.
Symbolication part is done in
https://github.com/facebook/react/pull/28471 and stacked on this commit.
There are not so many changes, most of them are changing imports,
because I've moved types for UI in a single file.
In https://github.com/facebook/react/pull/27357 I've added support for
pausing polling events: when user inspects an element, we start polling
React DevTools backend for updates in props / state. If user switches
tabs, extension's service worker can be killed by browser and this
polling will start spamming errors.
What I've missed is that we also have a separate call for this API, but
which is executed only once when user selects an element. We don't
handle promise rejection here and this can lead to some errors when user
selects an element and switches tabs right after it.
The only change here is that this API now has
`shouldListenToPauseEvents` param, which is `true` for polling, so we
will pause polling once user switches tabs. It is `false` by default, so
we won't pause initial call by accident.
af8beeebf6/packages/react-devtools-shared/src/backendAPI.js (L96)
## 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.
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.
## Summary
This pull request aims to improve the maintainability of the codebase by
consolidating types and constants that are shared between the backend
and frontend. This consolidation will allow us to maintain backwards
compatibility in the frontend in the future.
To achieve this, we have moved the shared types and constants to the
following blessed files:
- react-devtools-shared/src/constants
- react-devtools-shared/src/types
- react-devtools-shared/src/backend/types
- react-devtools-shared/src/backend/NativeStyleEditor/types
Please note that the inclusion of NativeStyleEditor in this list is
temporary, and we plan to remove it once we have a better plugin system
in place.
## How did you test this change?
I have tested it by running `yarn flow dom-node`, which reports no
errors.
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We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
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Before submitting a pull request, please make sure the following is
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1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
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`.
6. If you need a debugger, run `yarn debug-test --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
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
## Summary
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Explain the **motivation** for making this change. What existing problem
does the pull request solve?
-->
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.
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 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
* 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
Rationale: The only case where the unsupported dialog really matters is React Naive. That's the case where the frontend and backend versions are most likely to mismatch. In React Native, the backend is likely to send the bridge protocol version before sending operations– since the agent does this proactively during initialization.
I've tested the React Native starter app– after forcefully downgrading the backend version to 4.19.1 (see #23307 (comment)) and verified that this change "fixes" things. Not only does DevTools no longer throw an error that causes the UI to be hidden– it works (meaning that the Components tree can be inspected and interacted with).
* Move createRoot/hydrateRoot to /client
We want these APIs ideally to be imported separately from things you
might use in arbitrary components (like flushSync). Those other methods
are "isomorphic" to how the ReactDOM tree is rendered. Similar to hooks.
E.g. importing flushSync into a component that only uses it on the client
should ideally not also pull in the entry client implementation on the
server.
This also creates a nicer parity with /server where the roots are in a
separate entry point.
Unfortunately, I can't quite do this yet because we have some legacy APIs
that we plan on removing (like findDOMNode) and we also haven't implemented
flushSync using a flag like startTransition does yet.
Another problem is that we currently encourage these APIs to be aliased by
/profiling (or unstable_testing). In the future you don't have to alias
them because you can just change your roots to just import those APIs and
they'll still work with the isomorphic forms. Although we might also just
use export conditions for them.
For that all to work, I went with a different strategy for now where the
real API is in / but it comes with a warning if you use it. If you instead
import /client it disables the warning in a wrapper. That means that if you
alias / then import /client that will inturn import the alias and it'll
just work.
In a future breaking changes (likely when we switch to ESM) we can just
remove createRoot/hydrateRoot from / and move away from the aliasing
strategy.
* Update tests to import from react-dom/client
* Fix fixtures
* Update warnings
* Add test for the warning
* Update devtools
* Change order of react-dom, react-dom/client alias
I think the order matters here. The first one takes precedence.
* Require react-dom through client so it can be aliased
Co-authored-by: Andrew Clark <git@andrewclark.io>
React currently suppress console logs in StrictMode during double rendering. However, this causes a lot of confusion. This PR moves the console suppression logic from React into React Devtools. Now by default, we no longer suppress console logs. Instead, we gray out the logs in console during double render. We also add a setting in React Devtools to allow developers to hide console logs during double render if they choose.
The following APIs have been added to the `react` stable entry point:
* `SuspenseList`
* `startTransition`
* `unstable_createMutableSource`
* `unstable_useMutableSource`
* `useDeferredValue`
* `useTransition`
The following APIs have been added or removed from the `react-dom` stable entry point:
* `createRoot`
* `unstable_createPortal` (removed)
The following APIs have been added to the `react-is` stable entry point:
* `SuspenseList`
* `isSuspenseList`
The following feature flags have been changed from experimental to true:
* `enableLazyElements`
* `enableSelectiveHydration`
* `enableSuspenseServerRenderer`
Add an explicit Bridge protocol version to the frontend and backend components as well as a check during initialization to ensure that both are compatible. If not, the frontend will display either upgrade or downgrade instructions.
Note that only the `react-devtools-core` (React Native) and `react-devtools-inline` (Code Sandbox) packages implement this check. Browser extensions inject their own backend and so the check is unnecessary. (Arguably the `react-devtools-inline` check is also unlikely to be necessary _but_ has been added as an extra guard for use cases such as Replay.io.)
This commit adds a new tab to the Settings modal: Debugging
This new tab has the append component stacks feature and a new one: break on warn
This new feature adds a debugger statement into the console override
