* Remove object-assign polyfill
We really rely on a more modern environment where this is typically
polyfilled anyway and we don't officially support IE with more extensive
polyfilling anyway. So all environments should have the native version
by now.
* Use shared/assign instead of Object.assign in code
This is so that we have one cached local instance in the bundle.
Ideally we should have a compile do this for us but we already follow
this pattern with hasOwnProperty, isArray, Object.is etc.
* Transform Object.assign to now use shared/assign
We need this to use the shared instance when Object.spread is used.
The unstable-shared-subset.js file is not a public module — it's a
private module that the "react" package maps to when it's accessed from
the "react-server" package.
We originally added it because it was required to make our Rollup
configuration work, because at the time only "public" modules could act
as the entry point for a build artifact — that's why it's prefixed with
"unstable". We've since updated our Rollup config to support private
entry points, so we can remove the extra indirection.
Alternative to #23254
Our build script has a custom plugin to resolve internal module forks.
Currently, it uses require.resolve to resolve the path to a real file
on disk.
Instead, I've updated all the forked module paths to match their
location on disk, relative to the project root, to remove the need to
resolve them in the build script's runtime.
The main motivation is because require.resolve doesn't work with ESM
modules, but aside from that, hardcoding the relative paths is more
predictable — the Node module resolution algorithm is complicated, and
we don't really need its features for this purpose.
* Use consistent naming for unstable_testing entry point
* Exclude the testing build from non-experimental builds except at FB
* FB builds shouldn't contribute to whether we include the npm files
* Exclude exports fields if we delete the files entry
* Move test to no longer be internal so we can test against the build
* Update the bundle artifact names since they've now changed
* Gate import since it doesn't exist
* Move useSyncExternalStore shim to a nested entrypoint
Also renames `useSyncExternalStoreExtra` to
`useSyncExternalStoreWithSelector`.
- 'use-sync-external-store/shim' -> A shim for `useSyncExternalStore`
that works in React 16 and 17 (any release that supports hooks). The
module will first check if the built-in React API exists, before
falling back to the shim.
- 'use-sync-external-store/with-selector' -> An extended version of
`useSyncExternalStore` that also supports `selector` and `isEqual`
options. It does _not_ shim `use-sync-external-store`; it composes the
built-in React API. **Use this if you only support 18+.**
- 'use-sync-external-store/shim/with-selector' -> Same API, but it
composes `use-sync-external-store/shim` instead. **Use this for
compatibility with 16 and 17.**
- 'use-sync-external-store' -> Re-exports React's built-in API. Not
meant to be used. It will warn and direct users to either the shim or
the built-in API.
* Upgrade useSyncExternalStore to alpha channel
The event priority constants exports by the reconciler package are
meant to be used by the reconciler (host config) itself. So it doesn't
make sense to export them from a module that requires them.
To break the cycle, we can move them to a separate module and import
that. This looks like a "deep import" of an internal module, which we
try to avoid, but conceptually these are part of the public interface
of the reconciler module. So, no different than importing from the main
`react-reconciler`.
We do need to be careful about not mixing these types of imports with
implementation details. Those are the ones to really avoid.
An unintended benefit of the reconciler fork infra is that it makes
deep imports harder. Any module that we treat as "public", like this
one, needs to account for the `enableNewReconciler` flag and forward
to the correct implementation.
This configures the Flight fixture to use the "react-server" environment.
This allows the package.json exports field to specify a different resolution
in this environment.
I use this in the "react" package to resolve to a new bundle that excludes
the Hooks that aren't relevant in this environment like useState and useEffect.
This allows us to error early if these names are imported. If we actually
published ESM, it would we a static error. Now it's a runtime error.
You can test this by importing useState in Container.js which is used
by the client and server.
This updates the experimental Scheduler postTask build to call postTask
directly, instead of managing our own custom queue and work loop.
We still use a deadline 5ms mechanism to implement `shouldYield`.
The main thing that postTask is currently missing is the continuation
feature — when yielding to the main thread, the yielding task is sent
to the back of the queue, instead of maintaining its position.
While this would be nice to have, even without it, postTask may be good
enough to replace our userspace implementation.
We'll run some tests to see.
* Move unsubscribe fork to EventListener
That way we can statically compile out more of these indirections.
* Don't use the EventListener fork for Modern WWW builds
This PR adds the jsx-runtime and jsx-dev-runtime modules for the JSX Babel Plugin. WWW still relies on jsx/jsxs/jsxDEV from the "react" module, so once we refactor the code to point to the runtime modules we will remove jsx/jsxs/jsxDEV from the "react" module.
* ReactFiberReconciler -> ReactFiberReconciler.old
* Set up infra for react-reconciler fork
We're planning to land some significant refactors of the reconciler.
We want to be able to gradually roll out the new implementation side-by-
side with the existing one. So we'll create a short lived fork of the
react-reconciler package. Once the new implementation has stabilized,
we'll delete the old implementation and promote the new one.
This means, for as long as the fork exists, we'll need to maintain two
separate implementations. This sounds painful, but since the forks will
still be largely the same, most changes will not require two separate
implementations. In practice, you'll implement the change in the old
fork and then copy paste it to the new one.
This commit only sets up the build and testing infrastructure. It does
not actually fork any modules. I'll do that in subsequent PRs.
The forked version of the reconciler will be used to build a special
version of React DOM. I've called this build ReactDOMForked. It's only
built for www; there's no open source version.
The new reconciler is disabled by default. It's enabled in the
`yarn test-www-variant` command. The reconciler fork isn't really
related to the "variant" feature of the www builds, but I'm piggy
backing on that concept to avoid having to add yet another
testing dimension.
* Add ReactFlightServerConfig intermediate
This just forwards to the stream version of Flight which is itself forked
between Node and W3C streams.
The dom-relay goes directly to the Relay config though which allows it to
avoid the stream part of Flight.
* Separate streaming protocol into the Stream config
* Split streaming parts into the ReactFlightServerConfigStream
This decouples it so that the Relay implementation doesn't have to encode
the JSON to strings. Instead it can be fed the values as JSON objects and
do its own encoding.
* Split FlightClient into a basic part and a stream part
Same split as the server.
* Expose lower level async hooks to Relay
This requires an external helper file that we'll wire up internally.
* Rename to clarify that it's client-only
* Rename FizzStreamer to FizzServer for consistency
* Rename react-flight to react-client/flight
For consistency with react-server. Currently this just includes flight
but it could be expanded to include the whole reconciler.
* Add Relay Flight Build
* Rename ReactServerHostConfig to ReactServerStreamConfig
This will be the config specifically for streaming purposes.
There will be other configs for other purposes.
* 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.
* Check in a forked version of object-assign
This one uses ES modules so that we can inline it into UMD builds.
We could wait for object-assign to make an ESM export but we're going to
remove this dependency and assume global polyfills in the next version
anyway. However, we'd have to figure out how to keep the copyright header
and it'll get counted in terms of byte size (even if other tooling removes
it).
A lot of headache when we have our own implementation anyway. So I'll just
use that.
Ours is not resilient to checking certain browser bugs but those browsers
are mostly unused anyway. (Even FB breaks on them presumably.)
We also don't need to be resilient to Symbols since the way React uses it
we shouldn't need to copy symbols
* Don't transpile Object.assign to object-assign in object-assign
The polyfill needs to be able to feature detect Object.assign.
The testing build versions of react-dom are included in the builds right now, but we're not ready to share them yet. This PR removes them for now (back soon for the next release)
* 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.
* Replace all warning/lowPriWarning with console calls
* Replace console.warn/error with a custom wrapper at build time
* Fail the build for console.error/warn() where we can't read the stack
* Add Flight Build and Unify HostFormat Config between Flight and Fizz
* Add basic resolution of models
* Add basic Flight fixture
Demonstrates the streaming protocol.
* Rename to flight-server to distinguish from the client parts
* Add Flight Client package and entry point
* Fix fixture
* Rename lowPriorityWarning to lowPriorityWarningWithoutStack
This maintains parity with the other warning-like functions.
* Duplicate the toWarnDev tests to test toLowPriorityWarnDev
* Make a lowPriorityWarning version of warning.js
* Extract both variants in print-warning
Avoids parsing lowPriorityWarning.js itself as the way it forwards the
call to lowPriorityWarningWithoutStack is not analyzable.
* Rewrite ReactFiberScheduler
Adds a new implementation of ReactFiberScheduler behind a feature flag.
We will maintain both implementations in parallel until the new one
is proven stable enough to replace the old one.
The main difference between the implementations is that the new one is
integrated with the Scheduler package's priority levels.
* Conditionally add fields to FiberRoot
Some fields only used by the old scheduler, and some by the new.
* Add separate build that enables new scheduler
* Re-enable skipped test
If synchronous updates are scheduled by a passive effect, that work
should be flushed synchronously, even if flushPassiveEffects is
called inside batchedUpdates.
* Passive effects have same priority as render
* Revert ability to cancel the current callback
React doesn't need this anyway because it never schedules callbacks if
it's already rendering.
* Revert change to FiberDebugPerf
Turns out this isn't neccessary.
* Fix ReactFiberScheduler dead code elimination
Should initialize to nothing, then assign the exports conditionally,
instead of initializing to the old exports and then reassigning to the
new ones.
* Don't yield before commit during sync error retry
* Call Scheduler.flushAll unconditionally in tests
Instead of wrapping in enableNewScheduler flag.
* Transform invariant to custom error type
This transforms calls to the invariant module:
```js
invariant(condition, 'A %s message that contains %s', adj, noun);
```
Into throw statements:
```js
if (!condition) {
if (__DEV__) {
throw ReactError(`A ${adj} message that contains ${noun}`);
} else {
throw ReactErrorProd(ERR_CODE, adj, noun);
}
}
```
The only thing ReactError does is return an error whose name is set
to "Invariant Violation" to match the existing behavior.
ReactErrorProd is a special version used in production that throws
a minified error code, with a link to see to expanded form. This
replaces the reactProdInvariant module.
As a next step, I would like to replace our use of the invariant module
for user facing errors by transforming normal Error constructors to
ReactError and ReactErrorProd. (We can continue using invariant for
internal React errors that are meant to be unreachable, which was the
original purpose of invariant.)
* Use numbers instead of strings for error codes
* Use arguments instead of an array
I wasn't sure about this part so I asked Sebastian, and his rationale
was that using arguments will make ReactErrorProd slightly slower, but
using an array will likely make all the functions that throw slightly
slower to compile, so it's hard to say which way is better. But since
ReactErrorProd is in an error path, and fewer bytes is generally better,
no array is good.
* Casing nit
* Replace test renderer's fake Scheduler implementation with mock build
The test renderer has its own mock implementation of the Scheduler
interface, with the ability to partially render work in tests. Now that
this functionality has been lifted into a proper mock Scheduler build,
we can use that instead.
* Fix Profiler tests in prod
* Replace noop's fake Scheduler implementation with mock Scheduler build
The noop renderer has its own mock implementation of the Scheduler
interface, with the ability to partially render work in tests. Now that
this functionality has been lifted into a proper mock Scheduler build,
we can use that instead.
Most of the existing noop tests were unaffected, but I did have to make
some changes. The biggest one involved passive effects: previously, they
were scheduled on a separate queue from the queue that handles
rendering. After this change, both rendering and effects are scheduled
in the Scheduler queue. I think this is a better approach because tests
no longer have to worry about the difference; if you call `flushAll`,
all the work is flushed, both rendering and effects. But for those few
tests that do care to flush the rendering without the effects, that's
still possible using the `yieldValue` API.
Follow-up: Do the same for test renderer.
* Fix import to scheduler/unstable_mock
* Add new mock build of Scheduler with flush, yield API
Test environments need a way to take control of the Scheduler queue and
incrementally flush work. Our current tests accomplish this either using
dynamic injection, or by using Jest's fake timers feature. Both of these
options are fragile and rely too much on implementation details.
In this new approach, we have a separate build of Scheduler that is
specifically designed for test environments. We mock the default
implementation like we would any other module; in our case, via Jest.
This special build has methods like `flushAll` and `yieldValue` that
control when work is flushed. These methods are based on equivalent
methods we've been using to write incremental React tests. Eventually
we may want to migrate the React tests to interact with the mock
Scheduler directly, instead of going through the host config like we
currently do.
For now, I'm using our custom static injection infrastructure to create
the two builds of Scheduler — a default build for DOM (which falls back
to a naive timer based implementation), and the new mock build. I did it
this way because it allows me to share most of the implementation, which
isn't specific to a host environment — e.g. everything related to the
priority queue. It may be better to duplicate the shared code instead,
especially considering that future environments (like React Native) may
have entirely forked implementations. I'd prefer to wait until the
implementation stabilizes before worrying about that, but I'm open to
changing this now if we decide it's important enough.
* Mock Scheduler in bundle tests, too
* Remove special case by making regex more restrictive
