* Support Document as a container for hydration and rendering
Previously Document was not handled effectively as a container. in particual when hydrating if there was a fallback to client rendering React would attempt to append a new <html> element into the document before clearing out the existing one which errored leaving the application in brokent state.
The initial approach I took was to recycle the documentElement and never remove or append it, always just moving it to the right fiber and appending the right children (heady/body) as needed. However in testing a simple approach in modern browsers it seems like treating the documentElement like any other element works fine. This change modifies the clearContainer method to remove the documentElement if the container is a DOCUMENT_NODE. Once the container is cleared React can append a new documentElement via normal means.
* Allow Document as container for createRoot
previously rendering into Document was broken and only hydration worked because React did not properly deal with the documentElement and would error in a broken state if used that way. With the previous commit addressing this limitation this change re-adds Document as a valid container for createRoot.
It should be noted that if you use document with createRoot it will drop anything a 3rd party scripts adds the page before rendering for the first time.
The internal Container type represents the types of containers that React
can support in its internals that deal with containers.
This didn't include DocumentFragment which we support specifically for
rendering into shadow roots.
However, not all types makes sense to pass into the createRoot API.
One of those is comment nodes that is deprecated and we don't really fully
support. It really only exists for FB legacy.
For createRoot it doesn't make sense to pass a Document since that will try
to empty the document which removes the HTML tag which doesn't work.
Documents can only be passed to hydrateRoot.
Conversely I'm not sure we actually support hydrating a shadow root properly
so I excluded DocumentFragment from hydrateRoot.
* 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>
* move unstable_scheduleHydration to ReactDOMHydrationRoot
* move definition of schedule hydration
* fix test?
* prototype
* fix test
* remove gating because unstable_scheduleHydration is no longer gated through index.stable.js because its exposed through ReactDOMHydrationRoot instead of the ReactDOM package
* remove another gating
* 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.
* Move flushSync warning to React DOM
When you call in `flushSync` from an effect, React fires a warning. I've
moved the implementation of this warning out of the reconciler and into
React DOM.
`flushSync` is a renderer API, not an isomorphic API, because it has
behavior that was designed specifically for the constraints of React
DOM. The equivalent API in a different renderer may not be the same.
For example, React Native has a different threading model than the
browser, so it might not make sense to expose a `flushSync` API to the
JavaScript thread.
* Make root.unmount() synchronous
When you unmount a root, the internal state that React stores on the
DOM node is immediately cleared. So, we should also synchronously
delete the React tree. You should be able to create a new root using
the same container.
* Re-land recent flushSync changes
Adds back #21776 and #21775, which were removed due to an internal
e2e test failure.
Will attempt to fix in subsequent commits.
* Failing test: Legacy mode sync passive effects
In concurrent roots, if a render is synchronous, we flush its passive
effects synchronously. In legacy roots, we don't do this because all
updates are synchronous — so we need to flush at the beginning of the
next event. This is how `discreteUpdates` worked.
* Flush legacy passive effects at beginning of event
Fixes test added in previous commit.
* Replace flushDiscreteUpdates with flushSync
flushDiscreteUpdates is almost the same as flushSync. It forces passive
effects to fire, because of an outdated heuristic, which isn't ideal but
not that important.
Besides that, the only remaining difference between flushDiscreteUpdates
and flushSync is that flushDiscreteUpdates does not warn if you call it
from inside an effect/lifecycle. This is because it might get triggered
by a nested event dispatch, like `el.focus()`.
So I added a new method, flushSyncWithWarningIfAlreadyRendering, which
is used for the public flushSync API. It includes the warning. And I
removed the warning from flushSync, so the event system can call that
one. In production, flushSyncWithWarningIfAlreadyRendering gets inlined
to flushSync, so the behavior is identical.
Another way of thinking about this PR is that I renamed flushSync to
flushSyncWithWarningIfAlreadyRendering and flushDiscreteUpdates to
flushSync (and fixed the passive effects thing). The point is to prevent
these from subtly diverging in the future.
* Invert so the one with the warning is the default one
To make Seb happy
* Move internal version of act to shared module
No reason to have three different copies of this anymore.
I've left the the renderer-specific `act` entry points because legacy
mode tests need to also be wrapped in `batchedUpdates`. Next, I'll update
the tests to use `batchedUpdates` manually when needed.
* Migrates tests to use internal module directly
Instead of the `unstable_concurrentAct` exports. Now we can drop those
from the public builds.
I put it in the jest-react package since that's where we put our other
testing utilities (like `toFlushAndYield`). Not so much so it can be
consumed publicly (nobody uses that package except us), but so it works
with our build tests.
* Remove unused internal fields
These were used by the old act implementation. No longer needed.
Currently, in a React 18 root, `act` only works if you mock the
Scheduler package. This was because we didn't want to add additional
checks at runtime.
But now that the `act` testing API is dev-only, we can simplify its
implementation.
Now when an update is wrapped with `act`, React will bypass Scheduler
entirely and push its tasks onto a special internal queue. Then, when
the outermost `act` scope exists, we'll flush that queue.
I also removed the "wrong act" warning, because the plan is to move
`act` to an isomorphic entry point, simlar to `startTransition`. That's
not directly related to this PR, but I didn't want to bother
re-implementing that warning only to immediately remove it.
I'll add the isomorphic API in a follow up.
Note that the internal version of `act` that we use in our own tests
still depends on mocking the Scheduler package, because it needs to work
in production. I'm planning to move that implementation to a shared
(internal) module, too.
* Delete test-utils implementation of `act`
Since it's dev-only now, we can use the one provided by the reconciler.
* Move act related stuff out of EventInternals
This adds a new top level API for hydrating a root. It takes the initial
children as part of its constructor. These are unlike other render calls
in that they have to represent what the server sent and they can't be
batched with other updates.
I also changed the options to move the hydrationOptions to the top level
since now these options are all hydration options.
I kept the createRoot one just temporarily to make it easier to codemod
internally but I'm doing a follow up to delete.
As part of this I un-dried a couple of paths. ReactDOMLegacy was intended
to be built on top of the new API but it didn't actually use those root
APIs because there are special paths. It also doesn't actually use most of
the commmon paths since all the options are ignored. It also made it hard
to add only warnings for legacy only or new only code paths.
I also forked the create/hydrate paths because they're subtly different
since now the options are different. The containers are also different
because I now error for comment nodes during hydration which just doesn't
work at all but eventually we'll error for all createRoot calls.
After some iteration it might make sense to break out some common paths but
for now it's easier to iterate on the duplicates.
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`
Instead of LanePriority. Internally, EventPriority is just a lane, so
this skips an extra conversion. Since EventPriority is a "public" (to
the host config) type, I was also able to remove some deep imports
of the Lane module.
This gets us most of the way to deleting the LanePriority entirely.
Adds back the `TestUtils.act` implementation that I had removed
in #19745. This version of `act` is implemented in "userspace" (i.e. not
the reconciler), so it doesn't add to the production bundle size.
I had removed this in #19745 in favor of the `act` exported by the
reconciler because I thought we would remove support for `act` in
production in the impending major release. (It currently warns.)
However, we've since decided to continue supporting `act` in prod for
now, so that it doesn't block people from upgrading to v17. We'll drop
support in a future major release.
So, to avoid bloating the production bundle size, we need to move the
public version of `act` back to "userspace", like it was before.
This doesn't negate the main goal of #19745, though, which was to
decouple the public version(s) of `act` from the internal one that we
use to test React itself.
In the next major release, we intend to drop support for using the `act`
testing helper in production. (It already fires a warning.) The
rationale is that, in order for `act` to work, you must either mock the
testing environment or add extra logic at runtime. Mocking the testing
environment isn't ideal because it requires extra set up for the user.
Extra logic at runtime is fine only in development mode — we don't want
to slow down the production builds.
Since most people only run their tests in development mode, dropping
support for production should be fine; if there's demand, we can add it
back later using a special testing build that is identical to the
production build except for the additional testing logic.
One blocker for removing production support is that we currently use
`act` to test React itself. We must test React in both development and
production modes.
So, the solution is to fork `act` into separate public and
internal implementations:
- *public implementation of `act`* – exposed to users, only works in
development mode, uses special runtime logic, does not support partial
rendering
- *internal implementation of `act`* – private, works in both
development and productionm modes, only used by the React Core test
suite, uses no special runtime logic, supports partial rendering (i.e.
`toFlushAndYieldThrough`)
The internal implementation should mostly match the public
implementation's behavior, but since it's a private API, it doesn't have
to match exactly. It works by mocking the test environment: it uses a
mock build of Scheduler to flush rendering tasks, and Jest's mock timers
to flush Suspense placeholders.
---
In this first commit, I've added the internal forks of `act` and
migrated our tests to use them. The public `act` implementation is
unaffected for now; I will leave refactoring/clean-up for a later step.
* Set current update lane priority for user blocking events
* Update to use LanePriority and not use runWithPriority
* Remove unused imports
* Fix tests, and I missed ReactDOMEventListener
* Fix more tests
* Add try/finally and hardcode lane priorities instead
* Also hard code InputContinuousLanePriority in tests
* Remove un-needed exports
* Comment rollbacks
* Initial currentLanePriority implementation
* Minor updates from review
* Fix typos and enable flag
* Fix feature flags and lint
* Fix simple event tests by switching to withSuspenseConfig
* Don't lower the priority of setPending in startTransition below InputContinuous
* Move currentUpdateLanePriority in commit root into the first effect block
* Refactor requestUpdateLane to log for priority mismatches
Also verifies that the update lane priority matches the scheduler lane priority before using it
* Fix four tests by adding ReactDOM.unstable_runWithPriority
* Fix partial hydration when using update lane priority
* Fix partial hydration when using update lane priority
* Rename feature flag and only log for now
* Move unstable_runWithPriority to ReactFiberReconciler
* Add unstable_runWithPriority to ReactNoopPersistent too
* Bug fixes and performance improvements
* Initial currentLanePriority implementation
* Minor updates from review
* Fix typos and enable flag
* Remove higherLanePriority from ReactDOMEventReplaying.js
* Change warning implementation and startTransition update lane priority
* Inject reconciler functions to avoid importing src/
* Fix feature flags and lint
* Fix simple event tests by switching to withSuspenseConfig
* Don't lower the priority of setPending in startTransition below InputContinuous
* Move currentUpdateLanePriority in commit root into the first effect block
* Refactor requestUpdateLane to log for priority mismatches
Also verifies that the update lane priority matches the scheduler lane priority before using it
* Fix four tests by adding ReactDOM.unstable_runWithPriority
* Fix partial hydration when using update lane priority
* Fix partial hydration when using update lane priority
* Rename feature flag and only log for now
* Move unstable_runWithPriority to ReactFiberReconciler
* Bug fixes and performance improvements
* Remove higherLanePriority from ReactDOMEventReplaying.js
* Change warning implementation and startTransition update lane priority
* Inject reconciler functions to avoid importing src/
* Fixes from bad rebase
* Rename lower case isomorphic default exports modules to upper case named exports
We're somewhat inconsistent here between e.g. ReactLazy and memo.
Let's pick one.
This also moves the responder, fundamental, scope creators from shared
since they're isomorphic and same as the other creators.
* Move some files that are specific to the react-reconciler from shared
Individual renderers are allowed to deep require into the reconciler.
* Move files specific to react-dom from shared
react-interactions is right now dom specific (it wasn't before) so we can
type check it together with other dom stuff. Avoids the need for
a shared ReactDOMTypes to be checked by RN for example.
* Move ReactWorkTags to the reconciler
* Move createPortal to export from reconciler
Otherwise Noop can't access it since it's not allowed deep requires.
* Require deep for reconcilers
* Delete inline* files
* Delete react-reconciler/persistent
This no longer makes any sense because it react-reconciler takes
supportsMutation or supportsPersistence as options. It's no longer based
on feature flags.
* Fix jest mocking
* Fix Flow strategy
We now explicitly list which paths we want to be checked by a renderer.
For every other renderer config we ignore those paths.
Nothing is "any" typed. So if some transitive dependency isn't reachable
it won't be accidentally "any" that leaks.
* Add options for forked entry points
We currently fork .fb.js entry points. This adds a few more options.
.modern.fb.js - experimental FB builds
.classic.fb.js - stable FB builds
.fb.js - if no other FB build, use this for FB builds
.experimental.js - experimental builds
.stable.js - stable builds
.js - used if no other override exists
This will be used to have different ES exports for different builds.
* Switch React to named exports
* Export named exports from the export point itself
We need to re-export the Flow exported types so we can use them in our code.
We don't want to use the Flow types from upstream since it doesn't have the non-public APIs that we have.
This should be able to use export * but I don't know why it doesn't work.
This actually enables Flow typing of React which was just "any" before.
This exposed some Flow errors that needs fixing.
* Create forks for the react entrypoint
None of our builds expose all exports and they all differ in at least one
way, so we need four forks.
* Set esModule flag to false
We don't want to emit the esModule compatibility flag on our CommonJS
output. For now we treat our named exports as if they're CommonJS.
This is a potentially breaking change for scheduler (but all those apis
are unstable), react-is and use-subscription. However, it seems unlikely
that anyone would rely on this since these only have named exports.
* Remove unused Feature Flags
* Let jest observe the stable fork for stable tests
This lets it do the negative test by ensuring that the right tests fail.
However, this in turn will make other tests that are not behind
__EXPERIMENTAL__ fail. So I need to do that next.
* Put all tests that depend on exports behind __EXPERIMENTAL__
Since there's no way to override the exports using feature flags
in .intern.js anymore we can't use these APIs in stable.
The tradeoff here is that we can either enable the negative tests on
"stable" that means experimental are expected to fail, or we can disable
tests on stable. This is unfortunate since some of these APIs now run on
a "stable" config at FB instead of the experimental.
* Switch ReactDOM to named exports
Same strategy as React.
I moved the ReactDOMFB runtime injection to classic.fb.js
Since we only fork the entrypoint, the `/testing` entrypoint needs to
be forked too to re-export the same things plus `act`. This is a bit
unfortunate. If it becomes a pattern we can consider forking in the
module resolution deeply.
fix flow
* Fix ReactDOM Flow Types
Now that ReactDOM is Flow type checked we need to fix up its types.
* Configure jest to use stable entry for ReactDOM in non-experimental
* Remove additional FeatureFlags that are no longer needed
These are only flagging the exports and no implementation details so we
can control them fully through the export overrides.
Exports from ReactDOM represents React's public API. This include types
exported by React. At some point we'll start building Flow types from
these files.
The duplicate name between DOMContainer and Container seems confusing too
since it was used in the same files even though they're the same.
* Build both stable and experimental WWW builds
* Flip already experimental WWW flags to true
* Remove FB-specific internals from modern FB builds
We think we're not going to need these.
* Disable classic features in modern WWW builds
* Disable legacy ReactDOM API for modern WWW build
* Don’t include user timing in prod
* Fix bad copy paste and add missing flags to test renderer
* Add testing WWW feature flag file
We need it because WWW has a different meaning of experimental now.
This PR introduces adds `react/testing` and `react-dom/testing`.
- changes infra to generate these builds
- exports act on ReactDOM in these testing builds
- uses the new test builds in fixtures/dom
In the next PR -
- I'll use the new builds for all our own tests
- I'll replace usages of TestUtils.act with ReactDOM.act.
Josh Story
Sebastian Markbåge
Ricky
alireza molaee
salazarm
Andrew Clark
Brian Vaughn
Sebastian Markbåge
Dan Abramov
CY Lim
Dominic Gannaway
Nicolas Gallagher
Sunil Pai