* Add useOpaqueIdentifier Hook
We currently use unique IDs in a lot of places. Examples are:
* `<label for="ID">`
* `aria-labelledby`
This can cause some issues:
1. If we server side render and then hydrate, this could cause an
hydration ID mismatch
2. If we server side render one part of the page and client side
render another part of the page, the ID for one part could be
different than the ID for another part even though they are
supposed to be the same
3. If we conditionally render something with an ID , this might also
cause an ID mismatch because the ID will be different on other
parts of the page
This PR creates a new hook `useUniqueId` that generates a different
unique ID based on whether the hook was called on the server or client.
If the hook is called during hydration, it generates an opaque object
that will rerender the hook so that the IDs match.
Co-authored-by: Andrew Clark <git@andrewclark.io>
* 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.
* 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.
* Update Flow to 0.84
* Fix violations
* Use inexact object syntax in files from fbsource
* Fix warning extraction to use a modern parser
* Codemod inexact objects to new syntax
* Tighten types that can be exact
* Revert unintentional formatting changes from codemod
* allow nested `act()`s from different renderers
There are usecases where multiple renderers need to oprate inside an act() scope
- ReactDOM.render being used inside another component tree. The parent component will be rendered using ReactTestRenderer.create for a snapshot test or something.
- a ReactDOM instance interacting with a ReactTestRenderer instance (like for the new devtools)
This PR changes the way the acting sigils operate to allow for this. It keeps 2 booleans, one attached to React, one attached to the renderer. act() changes these values, and the workloop reads them to decide what warning to trigger.
I also renamed shouldWarnUnactedUpdates to warnsIfNotActing
* s/ReactIsActing/IsSomeRendererActing and s/ReactRendererIsActing/IsThisRendererActing
* use toWarnDev for dom fixture tests
forks toWarnDev from root into fixture/dom, updates tes tests to use it
* disable act() warnings for react-art()
- For 'secondary' renderers like react-act, we don't want to fire missing act() warnings; the wrapping renderer will fire warnings anyway, and when it flushes, it flushes effects *across* renderers.
- I could have used isPrimaryRenderer as the flag, but this is marked as false for react-test-renderer, and we *do* want the warning to fire for it. Hence a new flag.
* add missing dependency `art` to fixtures/dom
* [react-native] Use path-based imports instead of Haste for the RN renderer
To move React Native to standard path-based imports instead of Haste, the RN renderer that is generated from the code in this repo needs to use path-based imports as well since the generated code is vendored by RN. This commit makes it so the interface between the generated renderers and RN does not rely on Haste and instead uses a private interface explicitly defined by RN. This inverts control of the abstraction so that RN decides the internals to export rather than React deciding what to import.
On RN's side, a new module named `react-native/Libraries/ReactPrivate/ReactNativePrivateInterface` explicitly exports the modules used by the renderers in this repo. (There is also a private module for InitializeCore so that we can import it just for the side effects.) On React's side, the various renderer modules access RN internals through the explicit private interface.
The Rollup configuration becomes slimmer since the only external package is now `react-native`, and the individual modules are instead listed out in `ReactNativePrivateInterface`.
Task description: https://github.com/facebook/react-native/issues/24770
Sister RN PR (needs to land before this one): https://github.com/facebook/react-native/pull/24782
Test Plan: Ran unit tests and Flow in this repo. Generated the renderers and manually copied them over to the RN repo. Ran the RN tests and launched the RNTester app.
* Access natively defined "nativeFabricUIManager" instead of importing it
Some places in the Fabric renderers access `nativeFabricUIManager` (a natively defined global) instead of importing UIManager. While this is coupling across repos that depends on the timing of events, it is necessary until we have a way to defer top-level imports to run after `nativeFabricUIManager` is defined. So for consistency we use `nativeFabricUIManager` everywhere (see the comment in https://github.com/facebook/react/pull/15604#pullrequestreview-236842223 for more context).
* Import Scheduler directly, not via host config
We currently schedule asynchronous tasks via the host config. (The host
config is a static/build-time dependency injection system that varies
across different renderers — DOM, native, test, and so on.) Instead of
calling platform APIs like `requestIdleCallback` directly, each renderer
implements a method called `scheduleDeferredCallback`.
We've since discovered that when scheduling tasks, it's crucial that
React work is placed in the same queue as other, non-React work on the
main thread. Otherwise, you easily end up in a starvation scenario where
rendering is constantly interrupted by less important tasks. You need a
centralized coordinator that is used both by React and by other
frameworks and application code. This coordinator must also have a
consistent API across all the different host environments, for
convention's sake and so product code is portable — e.g. so the same
component can work in both React Native and React Native Web.
This turned into the Scheduler package. We will have different builds of
Scheduler for each of our target platforms. With this approach, we treat
Scheduler like a built-in platform primitive that exists wherever React
is supported.
Now that we have this consistent interface, the indirection of the host
config no longer makes sense for the purpose of scheduling tasks. In
fact, we explicitly do not want renderers to scheduled task via any
system except the Scheduler package.
So, this PR removes `scheduleDeferredCallback` and its associated
methods from the host config in favor of directly importing Scheduler.
* Missed an extraneous export
* Avoid importing Scheduler directly
The reconciler should not depend directly on Scheduler. This adds it to
the host config for the renderer instead.
(Except for `scheduler/tracing` imports, which are used only by the
profiling build. I've left those imports as-is, though I'm open to
directing those through the host config, too.)
* Make throwaway root id longer to appease Brian
Whenever we do this, Rollup needs to materialize this as an object.
This causes it to also add the Babel compatibility property which is
unnecessary bloat. However, since when we use these, we leak the object
this often also deopts any compiler optimizations.
If we really need an object we should export default an object.
Currently there is an exception for DOMTopLevelEventTypes since
listing out the imports is a PITA and it doesn't escape so it should
get properly inlined. We should probably move to a different pattern
to avoid this for consistency though.
This is required to use lazy.
Test Plan:
* Verified lazy works on a real world use case (shows spinner, shows real content).
* Verified that if I change the primary content's styles to have `display: 'none'` then it never appears (i.e., the code in `unhide` reads the styles successfully)
* [scheduler] Deadline object -> shouldYield
Instead of using a requestIdleCallback-style deadline object, expose a
method Scheduler.shouldYield that returns true if there's a higher
priority event in the queue.
* Nits
* Store the start time on `updateQueue` instead of `stateNode`
Originally I did this to free the `stateNode` field to store a second
set of children. I don't we'll need this anymore, since we use fragment
fibers instead. But I still think using `updateQueue` makes more sense
so I'll leave this in.
* Use fragment fibers to keep the primary and fallback children separate
If the children timeout, we switch to showing the fallback children in
place of the "primary" children. However, we don't want to delete the
primary children because then their state will be lost (both the React
state and the host state, e.g. uncontrolled form inputs). Instead we
keep them mounted and hide them. Both the fallback children AND the
primary children are rendered at the same time. Once the primary
children are un-suspended, we can delete the fallback children — don't
need to preserve their state.
The two sets of children are siblings in the host environment, but
semantically, for purposes of reconciliation, they are two separate
sets. So we store them using two fragment fibers.
However, we want to avoid allocating extra fibers for every placeholder.
They're only necessary when the children time out, because that's the
only time when both sets are mounted.
So, the extra fragment fibers are only used if the children time out.
Otherwise, we render the primary children directly. This requires some
custom reconciliation logic to preserve the state of the primary
children. It's essentially a very basic form of re-parenting.
* Use `memoizedState` to store various pieces of SuspenseComponent's state
SuspenseComponent has three pieces of state:
- alreadyCaptured: Whether a component in the child subtree already
suspended. If true, subsequent suspends should bubble up to the
next boundary.
- didTimeout: Whether the boundary renders the primary or fallback
children. This is separate from `alreadyCaptured` because outside of
strict mode, when a boundary times out, the first commit renders the
primary children in an incomplete state, then performs a second commit
to switch the fallback. In that first commit, `alreadyCaptured` is
false and `didTimeout` is true.
- timedOutAt: The time at which the boundary timed out. This is separate
from `didTimeout` because it's not set unless the boundary
actually commits.
These were previously spread across several fields.
This happens to make the non-strict case a bit less hacky; the logic for
that special case is now mostly localized to the UnwindWork module.
* Hide timed-out Suspense children
When a subtree takes too long to load, we swap its contents out for
a fallback to unblock the rest of the tree. Because we don't want
to lose the state of the timed out view, we shouldn't actually delete
the nodes from the tree. Instead, we'll keep them mounted and hide
them visually. When the subtree is unblocked, we un-hide it, having
preserved the existing state.
Adds additional host config methods. For mutation mode:
- hideInstance
- hideTextInstance
- unhideInstance
- unhideTextInstance
For persistent mode:
- cloneHiddenInstance
- cloneUnhiddenInstance
- createHiddenTextInstance
I've only implemented the new methods in the noop and test renderers.
I'll implement them in the other renderers in subsequent commits.
* Include `hidden` prop in noop renderer's output
This will be used in subsequent commits to test that timed-out children
are properly hidden.
Also adds getChildrenAsJSX() method as an alternative to using
getChildren(). (Ideally all our tests would use test renderer #oneday.)
* Implement hide/unhide host config methods for DOM renderer
For DOM nodes, we hide using `el.style.display = 'none'`.
Text nodes don't have style, so we hide using `text.textContent = ''`.
* Implement hide/unhide host config methods for Art renderer
* Create DOM fixture that tests state preservation of timed out content
* Account for class components that suspend outside concurrent mode
Need to distinguish mount from update. An unfortunate edge case :(
* Fork appendAllChildren between persistent and mutation mode
* Remove redundant check for existence of el.style
* Schedule placement effect on indeterminate components
In non-concurrent mode, indeterminate fibers may commit in an
inconsistent state. But when they update, we should throw out the
old fiber and start fresh. Which means the new fiber needs a
placement effect.
* Pass null instead of current everywhere in mountIndeterminateComponent
* Prepare placeholders before timing out
While a tree is suspended, prepare for the timeout by pre-rendering the
placeholder state.
This simplifies the implementation a bit because every render now
results in a completed tree.
* Suspend inside an already timed out Placeholder
A component should be able to suspend inside an already timed out
placeholder. The time at which the placeholder committed is used as
the start time for a subsequent suspend.
So, if a placeholder times out after 3 seconds, and an inner
placeholder has a threshold of 2 seconds, the inner placeholder will
not time out until 5 seconds total have elapsed.
* Inline fbjs/lib/emptyObject
* Explicit naming
* Compare to undefined
* Another approach for detecting whether we can mutate
Each renderer would have its own local LegacyRefsObject function.
While in general we don't want `instanceof`, here it lets us do a simple check: did *we* create the refs object?
Then we can mutate it.
If the check didn't pass, either we're attaching ref for the first time (so we know to use the constructor),
or (unlikely) we're attaching a ref to a component owned by another renderer. In this case, to avoid "losing"
refs, we assign them onto the new object. Even in that case it shouldn't "hop" between renderers anymore.
* Clearer naming
* Add test case for strings refs across renderers
* Use a shared empty object for refs by reading it from React
* Remove string refs from ReactART test
It's not currently possible to resetModules() between several renderers
without also resetting the `React` module. However, that leads to losing
the referential identity of the empty ref object, and thus subsequent
checks in the renderers for whether it is pooled fail (and cause assignments
to a frozen object).
This has always been the case, but we used to work around it by shimming
fbjs/lib/emptyObject in tests and preserving its referential identity.
This won't work anymore because we've inlined it. And preserving referential
identity of React itself wouldn't be great because it could be confusing during
testing (although we might want to revisit this in the future by moving its
stateful parts into a separate package).
For now, I'm removing string ref usage from this test because only this is
the only place in our tests where we hit this problem, and it's only
related to string refs, and not just ref mechanism in general.
* Simplify the condition
* Extract base Jest config
This makes it easier to change the source config without affecting the build test config.
* Statically import the host config
This changes react-reconciler to import HostConfig instead of getting it through a function argument.
Rather than start with packages like ReactDOM that want to inline it, I started with React Noop and ensured that *custom* renderers using react-reconciler package still work. To do this, I'm making HostConfig module in the reconciler look at a global variable by default (which, in case of the react-reconciler npm package, ends up being the host config argument in the top-level scope).
This is still very broken.
* Add scaffolding for importing an inlined renderer
* Fix the build
* ES exports for renderer methods
* ES modules for host configs
* Remove closures from the reconciler
* Check each renderer's config with Flow
* Fix uncovered Flow issue
We know nextHydratableInstance doesn't get mutated inside this function, but Flow doesn't so it thinks it may be null.
Help Flow.
* Prettier
* Get rid of enable*Reconciler flags
They are not as useful anymore because for almost all cases (except third party renderers) we *know* whether it supports mutation or persistence.
This refactoring means react-reconciler and react-reconciler/persistent third-party packages now ship the same thing.
Not ideal, but this seems worth how simpler the code becomes. We can later look into addressing it by having a single toggle instead.
* Prettier again
* Fix Flow config creation issue
* Fix imprecise Flow typing
* Revert accidental changes
Luna Ruan
Ricky
Sebastian Markbåge
Dominic Gannaway
Nicolas Gallagher
Dan Abramov
Sunil Pai
Sunil Pai
James Ide
Adam Comella
Andrew Clark
Sebastian Markbåge
Sophie Alpert
Andrew Clark
Héctor Ramos
Timothy Yung
Andrew Clark