@huozhi tried this out and says it's working as expected. I think we
can go ahead and move this into the stable channel, so that it is
available in the React 18 alpha releases.
* Add a failing test for Suspense hydration
* Include salazarm's changes to the test
* The hydration parent of a suspense boundary should be the boundary itself
This eventually got set when we popped back out of its children but it
doesn't start out that way.
This fixes it so that the boundary parent is always the suspense boundary.
* We now need to log errors with a suspense boundary as a parent
For now, we just log this with commentNode.parentNode as the parent for
purposes of the error message.
* Make a special getFirstHydratableChildWithinSuspenseInstance
We currently call getNextHydratableSibling but conceptually it's the child
of the boundary. It just happens to be that when we use comment nodes, we
need to call nextSibling in the DOM.
This makes this separation a bit clearer.
* Sync old fork
Co-authored-by: Dan Abramov <dan.abramov@me.com>
* Remove `jest` global check in concurrent roots
In concurrent mode, instead of checking `jest`, we check the new
`IS_REACT_ACT_ENVIRONMENT` global. The default behavior is `false`.
Legacy mode behavior is unchanged.
React's own internal test suite use a custom version of `act` that works
by mocking the Scheduler — rather than the "real" act used publicly. So
we don't enable the flag in our repo.
* Warn if `act` is called in wrong environment
Adds a warning if `act` is called but `IS_REACT_ACT_ENVIRONMENT` is not
enabled. The goal is to prompt users to correctly configure their
testing environment, so that if they forget to use `act` in a different
test, we can detect and warn about.
It's expected that the environment flag will be configured by the
testing framework. For example, a Jest plugin. We will link to the
relevant documentation page, once it exists.
The warning only fires in concurrent mode. Legacy roots will keep the
existing behavior.
* Extract `act` environment check into function
`act` checks the environment to determine whether to fire a warning.
We're changing how this check works in React 18. As a first step, this
refactors the logic into a single function. No behavior changes yet.
* Use IS_REACT_ACT_ENVIRONMENT to disable warnings
If `IS_REACT_ACT_ENVIRONMENT` is set to `false`, we will suppress
any `act` warnings. Otherwise, the behavior of `act` is the same as in
React 17: if `jest` is defined, it warns.
In concurrent mode, the plan is to remove the `jest` check and only warn
if `IS_REACT_ACT_ENVIRONMENT` is true. I have not implemented that
part yet.
## Summary
This commit is a proposal for handling duplicate installation of DevTools, in particular scoped to duplicates such as a dev build or the internal versions of DevTools installed alongside the Chrome Web Store extension.
Specifically, this commit makes it so when another instance of the DevTools extension is installed alongside the extension installed from the Chrome Web Store, we don't produce a stream of errors or crash Chrome, which is what would usually happen in this case.
### Detecting Duplicate Installations
- First, we check what type of installation the extension is: from the Chrome Web Store, the internal build of the extension, or a local development build.
- If the extension is from the **Chrome Web Store**:
- During initialization, we first check if the internal or local builds of the extension have already been installed and are enabled. To do this, we send a [cross-extension message](https://developer.chrome.com/docs/extensions/mv3/messaging/#external) to the internal and local builds of the extension using their extension IDs.
- We can do this because the extension ID for the internal build (and for the Chrome Web Store) is a stable ID.
- For the local build, at build time we hardcode a [`key` in the `manifest.json`](https://developer.chrome.com/docs/extensions/mv2/manifest/key/) which allows us to have a stable ID even for local builds.
- If we detect that the internal or local extensions are already installed, then we skip initializing the current extension altogether so as to not conflict with the other versions. This means we don't initialize the frontend or the backend at all.
- If the extension is the **Internal Build**:
- During initialization, we first check if the local builds of the extension has already been installed and is enabled. To do this, we send a [cross-extension message](https://developer.chrome.com/docs/extensions/mv3/messaging/#external) to the local build of the extension using its extension ID.
- We can do this for the local build because at build time we hardcode a [`key` in the `manifest.json`](https://developer.chrome.com/docs/extensions/mv2/manifest/key/) which allows us to have a stable ID even for local builds.
- If we detect that the local extension is already installed, then we skip initializing the current extension altogether so as to not conflict with the that version. This means we don't initialize the frontend or the backend at all.
- If the extension is a **Local Dev Build**:
- Since other extensions check for the existence of this extension and disable themselves if they detect it, we don't need any special handling during initialization and assume that there are no duplicate extensions. This means that we will generally prefer keeping this extension enabled.
This behavior means that the order of priority for keeping an extension enabled is the following:
1. Local build
2. Internal build
3. Public build
### Preventing duplicate backend initialization
Note that the backend is injected and initialized by the content script listening to a message posted to the inspected window (via `postMessage`). Since the content script will be injected twice, once each by each instance of the extension, even if we initialize the extension once, both content scripts would still receive the single message posted from the single frontend, and it would then still inject and initialize the backend twice.
In order to prevent this, we also add the extension ID to the message for injecting the backend. That way each content script can check if the message comes from its own extension, and if not it can ignore the message and avoid double injecting the backend.
### Other approaches
- I considered using the [`chrome.management`](https://developer.chrome.com/docs/extensions/reference/management/) API generally to detect other installations, but that requires adding additional permissions to our production extension, which didn't seem ideal.
- I also considered a few options of writing a special flag to the inspected window and checking for it before initializing the extension. However, it's hard to avoid race conditions in that case, and it seemed more reliable to check specifically for the WebStore extension, which is realistically where we would encounter the overlap.
### Rollout
- This commit needs to be published and rolled out to the Chrome Web Store first.
- After this commit is published to the Chrome Web Store, any duplicate instances of the extension that are built and installed after this commit will no longer conflict with the Chrome Web Store version.
### Next Steps
- In a subsequent PR, I will extend this code to show a warning when duplicate extensions have been detected.
Part of #22486
## How did you test this change?
### Basic Testing
- yarn flow
- yarn test
- yarn test-build-devtools
### Double installation testing
Testing double-installed extensions for this commit is tricky because we are relying on the extension ID of the internal and Chrome Web Store extensions, but we obviously can't actually test the Web Store version (since we can't modify the already published version).
In order to simulate duplicate extensions installed, I did the following process:
- Built separate extensions where I hardcoded a constant for whether the extension is internal or public (e.g. `EXTENSION_INSTALLATION_TYPE = 'internal'`). Then I installed these built extensions corresponding to the "internal" and "Web Store" builds.
- Build and run the regular development extension (with `yarn build:chrome:dev && yarn test:chrome`), using the extension IDs of the previously built extensions as the "internal" and "public" extension IDs.
With this set up in place, I tested the following on pages both with and without React:
- When only the local extension enabled, DevTools works normally.
- When only the "internal" extension enabled, DevTools works normally.
- When only the "public" extension enabled, DevTools works normally.
- When "internal" and "public" extensions are installed, "public" extension is disabled and "internal" extension works normally.
- When the local extension runs alongside the other extensions, other extensions disable themselves and local build works normally.
- When we can't recognize what type of build the extension corresponds to, we show an error.
- When all 3 extensions are installed and enabled in all different combinations, DevTools no longer produces errors or crashes Chrome, and works normally.
* Handle render phase updates explicitly
We fire a warning in development if a component is updated during
the render phase (with the exception of local hook updates, which have
their own defined behavior).
Because it's not a supported React pattern, we don't have that many
tests that trigger this path. But it is meant to have reasonable
semantics when it does happen, so that if it accidentally ships to
production, the app doesn't crash unnecessarily. The behavior is not
super well-defined, though.
There are also some _internal_ React implementation details that
intentionally to rely on this behavior. Most prominently, selective
hydration and useOpaqueIdentifier.
I need to tweak the behavior of render phase updates slightly as part
of a fix for useOpaqueIdentifier. This shouldn't cause a user-facing
change in behavior outside of useOpaqueIdentifier, but it does require
that we explicitly model render phase updates.
* Bugfix: Nested useOpaqueIdentifier calls
Fixes an issue where multiple useOpaqueIdentifier hooks are upgraded
to client ids within the same render.
The way the upgrade works is that useOpaqueIdentifier schedules a
render phase update then throws an error to trigger React's error
recovery mechanism.
The normal error recovery mechanism is designed for errors that occur
as a result of interleaved mutations, so we usually only retry a single
time, synchronously, before giving up.
useOpaqueIdentifier is different because the error its throws when
upgrading is not caused by an interleaved mutation. Rather, it happens
when an ID is referenced for the first time inside a client-rendered
tree (i.e. sommething that wasn't part of the initial server render).
The fact that it relies on the error recovery mechanism is an
implementation detail. And a single recovery attempt may be
insufficient. For example, if a parent and a child component may
reference different ids, and both are mounted as a result of the same
client update, that will trigger two separate error recovery attempts.
Because render phase updates are not allowed when triggered from
userspace — we log a warning in developement to prevent them —
we can assume that if something does update during the render phase, it
is one of our "legit" implementation details like useOpaqueIdentifier.
So we can keep retrying until we succeed — up to a limit, to protect
against inifite loops. I chose 50 since that's the limit we use for
commit phase updates.
* Rename pipeToNodeWritable to renderToNodePipe
* Add startWriting API to Flight
We don't really need it in this case because there's way less reason to
delay the stream in Flight.
* Pass the destination to startWriting instead of renderToNode
* Rename startWriting to pipe
This mirrors the ReadableStream API in Node
* Error codes
* Rename to renderToPipeableStream
This mimics the renderToReadableStream API for the browser.
* Hoist error codes import to module scope
When this code was written, the error codes map (`codes.json`) was
created on-the-fly, so we had to lazily require from inside the visitor.
Because `codes.json` is now checked into source, we can import it a
single time in module scope.
* Minify error constructors in production
We use a script to minify our error messages in production. Each message
is assigned an error code, defined in `scripts/error-codes/codes.json`.
Then our build script replaces the messages with a link to our
error decoder page, e.g. https://reactjs.org/docs/error-decoder.html/?invariant=92
This enables us to write helpful error messages without increasing the
bundle size.
Right now, the script only works for `invariant` calls. It does not work
if you throw an Error object. This is an old Facebookism that we don't
really need, other than the fact that our error minification script
relies on it.
So, I've updated the script to minify error constructors, too:
Input:
Error(`A ${adj} message that contains ${noun}`);
Output:
Error(formatProdErrorMessage(ERR_CODE, adj, noun));
It only works for constructors that are literally named Error, though we
could add support for other names, too.
As a next step, I will add a lint rule to enforce that errors written
this way must have a corresponding error code.
* Minify "no fallback UI specified" error in prod
This error message wasn't being minified because it doesn't use
invariant. The reason it didn't use invariant is because this particular
error is created without begin thrown — it doesn't need to be thrown
because it's located inside the error handling part of the runtime.
Now that the error minification script supports Error constructors, we
can minify it by assigning it a production error code in
`scripts/error-codes/codes.json`.
To support the use of Error constructors more generally, I will add a
lint rule that enforces each message has a corresponding error code.
* Lint rule to detect unminified errors
Adds a lint rule that detects when an Error constructor is used without
a corresponding production error code.
We already have this for `invariant`, but not for regular errors, i.e.
`throw new Error(msg)`. There's also nothing that enforces the use of
`invariant` besides convention.
There are some packages where we don't care to minify errors. These are
packages that run in environments where bundle size is not a concern,
like react-pg. I added an override in the ESLint config to ignore these.
* Temporarily add invariant codemod script
I'm adding this codemod to the repo temporarily, but I'll revert it
in the same PR. That way we don't have to check it in but it's still
accessible (via the PR) if we need it later.
* [Automated] Codemod invariant -> Error
This commit contains only automated changes:
npx jscodeshift -t scripts/codemod-invariant.js packages --ignore-pattern="node_modules/**/*"
yarn linc --fix
yarn prettier
I will do any manual touch ups in separate commits so they're easier
to review.
* Remove temporary codemod script
This reverts the codemod script and ESLint config I added temporarily
in order to perform the invariant codemod.
* Manual touch ups
A few manual changes I made after the codemod ran.
* Enable error code transform per package
Currently we're not consistent about which packages should have their
errors minified in production and which ones should.
This adds a field to the bundle configuration to control whether to
apply the transform. We should decide what the criteria is going
forward. I think it's probably a good idea to minify any package that
gets sent over the network. So yes to modules that run in the browser,
and no to modules that run on the server and during development only.
The `download-experimental-build` script has been flaky on CodeSandbox
CI, I think because of GitHub rate limiting.
Until we figure out how to fix that, I've updated it to fall back to a
local build.
* Pass in Destination lazily in startFlowing instead of createRequest
* Delay fatal errors until we have a destination to forward them to
* Flow can now be inferred by whether there's a destination set
We can drop the destination when we're not flowing since there's nothing to
write to.
Fatal errors now close once flowing starts back up again.
* Defer fatal errors in Flight too
As a follow up to #22445, this extracts the queueing logic that is
shared between `dispatchSetState` and `dispatchReducerAction` into
separate functions. It likely doesn't save any bytes since these will
get inlined, anyway, but it does make the flow a bit easier to follow.