## Summary
This PR improves the Trace Updates feature by letting developers see
component names directly on the update overlay. Before this change, the
overlay only highlighted updated regions, leaving it unclear which
components were involved. With this update, you can now match visual
updates to their corresponding components, making it much easier to
debug rendering performance.
### New Feature: Show component names while highlighting
When the new **"Show component names while highlighting"** setting is
enabled, the update overlay display the names of affected components
above the rectangles, along with the update count. This gives immediate
context about what’s rendering and why. The preference is stored in
local storage and synced with the backend, so it’s remembered across
sessions.
### Improvements to Drawing Logic
The drawing logic has been updated to make the overlay sharper and
easier to read. Overlay now respect device pixel ratios, so they look
great on high-DPI screens. Outlines have also been made crisper, which
makes it easier to spot exactly where updates are happening.
> [!NOTE]
> **Grouping Logic and Limitations**
> Updates are grouped by their screen position `(left, top coordinates)`
to combine overlapping or nearby regions into a single group. Groups are
sorted by the highest update count within each group, making the most
frequently updated components stand out.
> Overlapping labels may still occur when multiple updates involve
components that overlap but are not in the exact same position. This is
intentional, as the logic aims to maintain a straightforward mapping
between update regions and component names without introducing
unnecessary complexity.
### Testing
This PR also adds tests for the new `groupAndSortNodes` utility, which
handles the logic for grouping and sorting updates. The tests ensure the
behavior is reliable across different scenarios.
## Before & After
https://github.com/user-attachments/assets/6ea0fe3e-9354-44fa-95f3-9a867554f74chttps://github.com/user-attachments/assets/32af4d98-92a5-47dd-a732-f05c2293e41b
---------
Co-authored-by: Ruslan Lesiutin <rdlesyutin@gmail.com>
Stacked on https://github.com/facebook/react/pull/31132. See last
commit.
There are 2 issues:
1. We've been recording timeline events, even if Timeline Profiler was
not supported by the Host. We've been doing this for React Native, for
example, which would significantly regress perf of recording a profiling
session, but we were not even using this data.
2. Currently, we are generating component stack for every state update
event. This is extremely expensive, and we should not be doing this.
We can't currently fix the second one, because we would still need to
generate all these stacks, and this would still take quite a lot of
time. As of right now, we can't generate a component stack lazily
without relying on the fact that reference to the Fiber is not stale.
With `enableOwnerStacks` we could populate component stacks in some
collection, which would be cached at the Backend, and then returned only
once Frontend asks for it. This approach also eliminates the need for
keeping a reference to a Fiber.
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## Summary
In preparation to support reload-to-profile in Fusebox (#31021), we need
a way to check capability of different backends, e.g. web vs React
Native.
## How did you test this change?
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* Default, e.g. existing web impl = no-op
* Custom impl: is called
Stacked on https://github.com/facebook/react/pull/30597 and whats under
it. See [this
commit](59b4efa723).
With this change, the initial values for console patching settings are
propagated from hook (which is the source of truth now, because of
https://github.com/facebook/react/pull/30596) to the UI. Instead of
reading from `localStorage` the frontend is now requesting it from the
hook. This happens when settings modal is rendered, and wrapped in a
transition. Also, this is happening even if settings modal is not opened
yet, so we have enough time to fetch this data without displaying loader
or similar UI.
Stacked on https://github.com/facebook/react/pull/30566 and whats under
it. See [this
commit](374fd737e4).
It is mostly copying code from one place to another and updating tests.
With these changes, for every console method that we patch, there is
going to be a single applied patch:
- For `error`, `warn`, and `trace` we are patching when hook is
installed. This guarantees that component stacks are going to be
appended even if browser DevTools are not opened. We pay some price for
it, though: if user has browser DevTools closed and if at this point
some warning or error is emitted (logged), the next time user opens
browser DevTools, they are going to see `hook.js` as the source frame.
Unfortunately, ignore listing from source maps is not applied
retroactively, and I don't know if its a bug or just a design
limitations. Once browser DevTools are opened, source maps will be
loaded and ignore listing will be applied for all emitted logs in the
future.
- For `log`, `info`, `group`, `groupCollapsed` we are only patching when
React notifies React DevTools about running in StrictMode. We unpatch
the methods right after it.
The current state is that `rendererInterface`, which contains all the
backend logic, like generating component stack or attaching errors to
fibers, or traversing the Fiber tree, ..., is only mounted after the
Frontend is created.
For browser extension, this means that we don't patch console or track
errors and warnings before Chrome DevTools is opened.
With these changes, `rendererInterface` is created right after
`renderer` is injected from React via global hook object (e. g.
`__REACT_DEVTOOLS_GLOBAL_HOOK__.inject(...)`.
Because of the current implementation, in case of multiple Reacts on the
page, all of them will patch the console independently. This will be
fixed in one of the next PRs, where I am moving console patching to the
global Hook.
This change of course makes `hook.js` script bigger, but I think it is a
reasonable trade-off for better DevX. We later can add more heuristics
to optimize the performance (if necessary) of `rendererInterface` for
cases when Frontend was connected late and Backend is attempting to
flush out too many recorded operations.
This essentially reverts https://github.com/facebook/react/pull/26563.
Both for browser extension, and for React Native (as part of
`react-devtools-core`) `Store` is initialized before the Backend (and
`Agent` as a part of it):
bac33d1f82/packages/react-devtools-extensions/src/main/index.js (L111-L113)
Any messages that we send from `Store`'s constructor are ignored,
because there is nothing on the other end yet. With these changes,
`Agent` will send `backendInitialized` message to `Store`, after which
`getBackendVersion` and other events will be sent.
Note that `isBackendStorageAPISupported` and `isSynchronousXHRSupported`
are still sent from `Agent`'s constructor, because we don't explicitly
ask for it from `Store`, but these are used.
This the pre-requisite for fetching settings and unsupported renderers
reliably from the Frontend.
Stacked on #30842.
This adds a filter to be able to exclude Components from a certain
environment. Default to Client or Server.
The available options are computed into a dropdown based on the names
that are currently used on the page (or an option that were previously
used). In addition to the hardcoded "Client". Meaning that if you have
Server Components on the page you see "Server" or "Client" as possible
options but it can be anything if there are multiple RSC environments on
the page.
"Client" in this case means Function and Class Components in Fiber -
excluding built-ins.
If a Server Component has two environments (primary and secondary) then
both have to be filtered to exclude it.
We don't show the option at all if there are no Server Components used
in the page to avoid confusing existing users that are just using Client
Components and wouldn't know the difference between Server vs Client.
<img width="815" alt="Screenshot 2024-08-30 at 12 56 42 AM"
src="https://github.com/user-attachments/assets/e06b225a-e85d-4cdc-8707-d4630fede19e">
There's two problems. The biggest one is that it turns out that Chrome
is throttling looping timers that we're using both while polling and for
batching bridge traffic. This means that bridge traffic a lot of the
time just slows down to 1 second at a time. No wonder it feels sluggish.
The only solution is to not use timers for this.
Even when it doesn't like in Firefox the batching into 100ms still feels
too sluggish.
The fix I use is to batch using a microtask instead so we can still
batch multiple commands sent in a single event but we never artificially
slow down an interaction.
I don't think we've reevaluated this for a long time since this was in
the initial commit of DevTools to this repo. If it causes other issues
we can follow up on those.
We really shouldn't use timers for debouncing and such. In fact, React
itself recommends against it because we have a better technique with
scheduling in Concurrent Mode. The correct way to implement this in the
bridge is using a form of back-pressure where we don't keep sending
messages until we get a message back and only send the last one that
matters. E.g. when moving the cursor over a the elements tab we
shouldn't let the backend one-by-one move the DOM node to each one we
have ever passed. We should just move to the last one we're currently
hovering over. But this can't be done at the bridge layer since it
doesn't know if it's a last-one-wins or imperative operation where each
one needs to be sent. It needs to be done higher. I'm not currently
seeing any perf problems with this new approach but I'm curious on React
Native or some thing. RN might need the back-pressure approach. That can
be a follow up if we ever find a test case.
Finally, the other problem is that we use a Suspense boundary around the
Element Inspection. Suspense boundaries are for things that are expected
to take a long time to load. This shows a loading state immediately. To
avoid flashing when it ends up being fast, React throttles the reveal to
200ms. This means that we take a minimum of 200ms to show the props. The
way to show fast async data in React is using a Transition (either using
startTransition or useDeferredValue). This lets the old value remaining
in place while we're loading the next one.
We already implement this using `inspectedElementID` which is the async
one. It would be more idiomatic to implement this with useDeferredValue
rather than the reducer we have now but same principle. We were just
using the wrong ID in a few places so when it synchronously updated they
suspended. So I just made them use the inspectedElementID instead.
Then I can simply remove the Suspense boundary. Now the selection
updates in the tree view synchronously and the sidebar lags a frame or
two but it feels instant. It doesn't flash to white between which is
key.
Stacked on #30490.
This is in the same spirit but to clarify the difference between what is
React Native vs part of any generic Host. We used to use "Native" to
mean three different concepts. Now "Native" just means React Native.
E.g. from the frontend's perspective the Host can be
Highlighted/Inspected. However, that in turn can then be implemented as
either direct DOM manipulation or commands to React Native. So frontend
-> backend is "Host" but backend -> React Native is "Native" while
backend -> DOM is "Web".
Rename NativeElementsPanel to BuiltinElementsPanel. This isn't a React
Native panel but one part of the surrounding DevTools. We refer to Host
more as the thing running React itself. I.e. where the backend lives.
The runtime you're inspecting. The DevTools itself needs a third term.
So I went with "Builtin".
I need to start clarifying where things are really actually Fibers and
where they're not since I'm adding Server Components as a separate type
of component instance which is not backed by a Fiber.
Nothing in the front end should really know anything about what kind of
renderer implementation we're inspecting and indeed it's already not
always a "Fiber" in the legacy renderer.
We typically refer to this as a "Component Instance" but the front end
currently refers to it as an Element as it historically grew from the
browser DevTools Elements tab.
I also moved the renderer.js implementation into the `backend/fiber`
folder. These are at the same level as `backend/legacy`. This clarifies
that anything outside of this folder ideally shouldn't refer to a
"Fiber".
console.js and profilingHooks.js unfortunately use Fibers a lot which
needs further refactoring. The profiler frontend also uses the term
alot.
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)
Some context:
- When user selects an element in tree inspector, we display current
state of the component. In order to display really current state, we
start polling the backend to get available updates for the element.
Previously:
- Straight-forward sending an event to get element updates each second.
Potential race condition is not handled in any form.
- If user navigates from the page, timeout wouldn't be cleared and we
would potentially throw "Timed out ..." error.
- Bridge disconnection is not handled in any form, if it was shut down,
we could spam with "Timed out ..." errors.
With these changes:
- Requests are now chained, so there can be a single request at a time.
- Handling both navigation and shut down events.
This should reduce the number of "Timed out ..." errors that we see in
our logs for the extension. Other surfaces will also benefit from it,
but not to the full extent, as long as they utilize
"resumeElementPolling" and "pauseElementPolling" events.
Tested this on Chrome, running React DevTools on multiple tabs,
explicitly checked the case when service worker is in idle state and we
return back to the tab.
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## Summary
Fix devtools cannot be shutdown by bridge.shutdown().
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## How did you test this change?
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Fixes https://github.com/facebook/react/issues/26500
## Summary
- No more using `clipboard-js` from the backend side, now emitting
custom `saveToClipboard` event, also adding corresponding listener in
`store.js`
- Not migrating to `navigator.clipboard` api yet, there were some issues
with using it on Chrome, will add more details to
https://github.com/facebook/react/pull/26539
## How did you test this change?
- Tested on Chrome, Firefox, Edge
- Tested on standalone electron app: seems like context menu is not
expected to work there (cannot right-click on value, the menu is not
appearing), other logic (pressing on copy icon) was not changed
## 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.
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
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.
# Summary
* This PR adds support for persisting certain settings to device
storage, allowing e.g. RN apps to properly patch the console when
restarted.
* The device storage APIs have signature `getConsolePatchSettings()` and
`setConsolePatchSettings(string)`, in iOS, are thin wrappers around the
`Library/Settings` turbomodule, and wrap a new TM that uses the `SharedPreferences` class in Android.
* Pass device storage getters/setters from RN to DevTools'
`connectToDevtools`. The setters are then used to populate values on
`window`. Later, the console is patched using these values.
* If we receive a notification from DevTools that the console patching
fields have been updated, we write values back to local storage.
* See https://github.com/facebook/react-native/pull/34903
# How did you test this change?
Manual testing, `yarn run test-build-devtools`, `yarn run prettier`,
`yarn run flow dom`
## Manual testing setup:
### React DevTools Frontend
* Get the DevTools frontend in flipper:
* `nvm install -g react-devtools-core`, then replace that package with a
symlink to the local package
* enable "use globally installed devtools" in flipper
* yarn run start in react-devtools, etc. as well
### React DevTools Backend
* `yarn run build:backend` in react-devtools-core, then copy-paste that
file to the expo app's node_modules directory
### React Native
* A local version of React Native can be patched in by modifying an expo
app's package.json, as in `"react-native":
"rbalicki2/react-native#branch-name"`
# Versioning safety
* There are three versioned modules to worry about: react native, the
devtools frontend and the devtools backend.
* The react devtools backend checks for whether a `cachedSettingsStore`
is passed from react native. If not (e.g. if React Native is outdated),
then no behavior changes.
* The devtools backend reads the patched console values from the cached
settings store. However, if nothing has been stored, for example because
the frontend is outdated or has never synced its settings, then behavior
doesn't change.
* The devtools frontend sends no new messages. However, if it did send a
new message (e.g. "store this value at this key"), and the backend was
outdated, that message would be silently ignored.
* 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).
This information can help with bug investigation for renderers (like React Native) that embed the DevTools backend into their source (separately from the DevTools frontend, which gets run by the user).
If the DevTools backend is too old to report a version, or if the version reported is the same as the frontend (as will be the case with the browser extension) then only a single version string will be shown, as before. If a different version is reported, then both will be shown separately.
This is being done so that we can embed DevTools within the new React (beta) docs.
The primary changes here are to `react-devtools-inline/backend`:
* Add a new `createBridge` API
* Add an option to the `activate` method to support passing in the custom bridge object.
The `react-devtools-inline` README has been updated to include these new methods.
To verify these changes, this commit also updates the test shell to add a new entry-point for multiple DevTools.
This commit also replaces two direct calls to `window.postMessage()` with `bridge.send()` (and adds the related Flow types).
Adds the concept of subtree modes to DevTools to bridge protocol as follows:
1. Add-root messages get two new attributes: one specifying whether the root is running in strict mode and another specifying whether the root (really the root's renderer) supports the concept of strict mode.
2. A new backend message type (TREE_OPERATION_SET_SUBTREE_MODE). This type specifies a subtree root (id) and a mode (bitmask). For now, the only mode this message deals with is strict mode.
The DevTools frontend has been updated as well to highlight non-StrictMode compliant components.
The changes to the bridge protocol require incrementing the bridge protocol version number, which will also require updating the version of react-devtools-core backend that is shipped with React Native.
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.
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.)
* Restore inspect-element bridge optimizations
When the new Suspense cache was integrated (so that startTransition could be used) I removed a couple of optimizations between the backend and frontend that reduced bridge traffic when e.g. dehydrated paths were inspected for elements that had not rendered since previously inspected. This commit re-adds those optimizations as well as an additional test with a bug fix that I noticed while reading the backend code.
There are two remaining TODO items as of this commit:
- Make inspected element edits and deletes also use transition API
- Don't over-eagerly refresh the cache in our ping-for-updates handler
I will addres both in subsequent commits.
* Poll for update only refreshes cache when there's an update
* Added inline comment
DevTools was built with a fork of an early idea for how Suspense cache might work. This idea is incompatible with newer APIs like `useTransition` which unfortunately prevented me from making certain UX improvements. This PR swaps out the primary usage of this cache (there are a few) in favor of the newer `unstable_getCacheForType` and `unstable_useCacheRefresh` APIs. We can go back and update the others in follow up PRs.
### Messaging changes
I've refactored the way the frontend loads component props/state/etc to hopefully make it better match the Suspense+cache model. Doing this gave up some of the small optimizations I'd added but hopefully the actual performance impact of that is minor and the overall ergonomic improvements of working with the cache API make this worth it.
The backend no longer remembers inspected paths. Instead, the frontend sends them every time and the backend sends a response with those paths. I've also added a new "force" parameter that the frontend can use to tell the backend to send a response even if the component hasn't rendered since the last time it asked. (This is used to get data for newly inspected paths.)
_Initial inspection..._
```
front | | back
| -- "inspect" (id:1, paths:[], force:true) ---------> |
| <------------------------ "inspected" (full-data) -- |
```
_1 second passes with no updates..._
```
| -- "inspect" (id:1, paths:[], force:false) --------> |
| <------------------------ "inspected" (no-change) -- |
```
_User clicks to expand a path, aka hydrate..._
```
| -- "inspect" (id:1, paths:['foo'], force:true) ----> |
| <------------------------ "inspected" (full-data) -- |
```
_1 second passes during which there is an update..._
```
| -- "inspect" (id:1, paths:['foo'], force:false) ---> |
| <----------------- "inspectedElement" (full-data) -- |
```
### Clear errors/warnings transition
Previously this meant there would be a delay after clicking the "clear" button. The UX after this change is much improved.
### Hydrating paths transition
I also added a transition to hydration (expanding "dehyrated" paths).
### Better error boundaries
I also added a lower-level error boundary in case the new suspense operation ever failed. It provides a better "retry" mechanism (select a new element) so DevTools doesn't become entirely useful. Here I'm intentionally causing an error every time I select an element.
### Improved snapshot tests
I also migrated several of the existing snapshot tests to use inline snapshots and added a new serializer for dehydrated props. Inline snapshots are easier to verify and maintain and the new serializer means dehydrated props will be formatted in a way that makes sense rather than being empty (in external snapshots) or super verbose (default inline snapshot format).
* Improve DevTools editing interface
This commit adds the ability to rename or delete keys in the props/state/hooks/context editor and adds tests to cover this functionality. DevTools will degrade gracefully for older versions of React that do not inject the new reconciler rename* or delete* methods.
Specifically, this commit includes the following changes:
* Adds unit tests (for modern and legacy renderers) to cover overriding props, renaming keys, and deleting keys.
* Refactor backend override methods to reduce redundant Bridge/Agent listeners and methods.
* Inject new (DEV-only) methods from reconciler into DevTools to rename and delete paths.
* Refactor 'inspected element' UI components to improve readability.
* Improve auto-size input to better mimic Chrome's Style editor panel. (See this Code Sandbox for a proof of concept.)
It also contains the following code cleanup:
* Additional unit tests have been added for modifying values as well as renaming or deleting paths.
* Four new DEV-only methods have been added to the reconciler to be injected into the DevTools hook: overrideHookStateDeletePath, overrideHookStateRenamePath, overridePropsDeletePath, and overridePropsRenamePath. (DevTools will degrade gracefully for older renderers without these methods.)
* I also took this as an opportunity to refactor some of the existing code in a few places:
* Rather than the backend implementing separate methods for editing props, state, hooks, and context– there are now three methods: deletePath, renamePath, and overrideValueAtPath that accept a type argument to differentiate between props, state, context, or hooks.
* The various UI components for the DevTools frontend have been refactored to remove some unnecessary repetition.
This commit also adds temporary support for override* commands with mismatched backend/frontend versions:
* Add message forwarding for older backend methods (overrideContext, overrideHookState, overrideProps, and overrideState) to the new overrideValueAtPath method. This was done in both the frontend Bridge (for newer frontends passing messages to older embedded backends) and in the backend Agent (for older frontends passing messages to newer backends). We do this because React Native embeds the React DevTools backend, but cannot control which version of the frontend users use.
* Additional unit tests have been added as well to cover the older frontend to newer backend case. Our DevTools test infra does not make it easy to write tests for the other way around.
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
DevTools previously used the NPM events package for dispatching events. This package has an unfortunate flaw though- if a listener throws during event dispatch, no subsequent listeners are called. I've replaced that event dispatcher with my own implementation that ensures all listeners are called before it re-throws an error.
This commit replaces that event emitter with a custom implementation that calls all listeners before re-throwing an error.
* Added rudimentary context menu hook and menu UI
* Added backend support for copying a value at a specific path for the inspected element
* Added backend support for storing a value (at a specified path) as a global variable
* Added special casing to enable copying undefined/unserializable values to the clipboard
* Added copy and store-as-global context menu options to selected element props panel
* Store global variables separately, with auto-incremented name (like browsers do)
* Added tests for new copy and store-as-global backend functions
* Fixed some ownerDocument/contentWindow edge cases
* Refactored context menu to support dynamic options
Used this mechanism to add a conditional menu option for inspecting the current value (if it's a function)
* Renamed "safeSerialize" to "serializeToString" and added inline comment
