The useState hook has always composed the useReducer hook. 1:1 composition like this is fine.
But some more recent hooks (e.g. useTransition, useDeferredValue) compose multiple hooks internally. This breaks react-debug-tools because it causes off-by-N errors when the debug tools re-renders the function.
For example, if a component were to use the useTransition and useMemo hooks, the normal hooks dispatcher would create a list of first state, then callback, then memo hooks, but the debug tools package would expect a list of transition then memo. This can break user code and cause runtime errors in both the react-debug-tools package and in product code.
This PR fixes the currently broken hooks by updating debug tools to be aware of the composite hooks (how many times it should call nextHook essentially) and adds tests to make sure they don't get out of sync again. We'll need to add similar tests for future composite hooks (like useMutableSource #18000).
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)
We're not actually building this entry point. I can't think of a reason
we'd need to fork the isomorphic one. We don't really fork it for
anything since it's so generic to work with all renderers.
Since /profiling doesn't have this, it might confuse the story if we made
people alias two things for testing but not profiling.
* 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.
* [eslint-plugin-react-hooks] Fix cyclic caching for loops containing a condition
* [eslint-plugin-react-hooks] prettier write
* [eslint-plugin-react-hooks] Fix set for tests
* Update packages/eslint-plugin-react-hooks/src/RulesOfHooks.js
Co-Authored-By: Luke Kang <[email protected]>
Co-authored-by: Luke Kang <[email protected]>
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.
* import * as React from "react";
This is the correct way to import React from an ES module since the ES
module will not have a default export. Only named exports.
* import * as ReactDOM from "react-dom"
I recently landed a change to the timing of passive effect cleanup functions during unmount (see #17925). This change defers flushing of passive effects for unmounted components until later (whenever we next flush pending passive effects).
Since this change increases the likelihood of a (not actionable) state update warning for unmounted components, I've suppressed that warning for Fibers that have scheduled passive effect unmounts pending.
Fixes a bug where lower priority updates on a components wrapped with
`memo` are sometimes left dangling in the queue without ever being
processed, if they are preceded by a higher priority bailout.
Cause
-----
The pending update priority field is cleared at the beginning of
`beginWork`. If there is remaining work at a lower priority level, it's
expected that it will be accumulated on the work-in-progress fiber
during the begin phase.
There's an exception where this assumption doesn't hold:
SimpleMemoComponent contains a bailout that occurs *before* the
component is evaluated and the update queues are processed, which means
we don't accumulate the next priority level. When we complete the fiber,
the work loop is left to believe that there's no remaining work.
Mitigation
----------
Since this only happens in a single case, a late bailout in
SimpleMemoComponent, I've mitigated the bug in that code path by
restoring the original update priority from the current fiber.
This same case does not apply to MemoComponent, because MemoComponent
fibers do not contain hooks or update queues; rather, they wrap around
an inner fiber that may contain those. However, I've added a test case
for MemoComponent to protect against a possible future regression.
Possible next steps
-------------------
We should consider moving the update priority assignment in `beginWork`
out of the common path and into each branch, to avoid similar bugs in
the future.
Adds a feature flag for when React.jsx warns you about spreading a key into jsx. It's false for all builds, except as a dynamic flag for fb/www.
I also included the component name in the warning.
This warning already exists for class components, but not for functions.
It does not apply to render phase updates to the same component, which
have special semantics that we do support.
Our current lint config assumes a browser environment, which means it won't warn you if you use a variable like `name` without declaring it earlier. This imports the same list as the one used by create-react-app, and enables it against our codebase.
* Re-throw errors thrown by the renderer at the root
React treats errors thrown at the root as a fatal because there's no
parent component that can capture it. (This is distinct from an
"uncaught error" that isn't wrapped in an error boundary, because in
that case we can fall back to deleting the whole tree -- not great, but
at least the error is contained to a single root, and React is left in a
consistent state.)
It turns out we didn't have a test case for this path. The only way it
can happen is if the renderer's host config throws. We had similar test
cases for host components, but none for the host root.
This adds a new test case and fixes a bug where React would keep
retrying the root because the `workInProgress` pointer was not advanced
to the next fiber. (Which in this case is `null`, since it's the root.)
We could consider in the future trying to gracefully exit from certain
types of root errors without leaving React in an inconsistent state. For
example, we should be able to gracefully exit from errors thrown in the
begin phase. For now, I'm treating it like an internal invariant and
immediately exiting.
* Add comment
* Split recent passive effects changes into 2 flags
Separate flags can now be used to opt passive effects into:
1) Deferring destroy functions on unmount to subsequent passive effects flush
2) Running all destroy functions (for all fibers) before create functions
This allows us to test the less risky feature (2) separately from the more risky one.
* deferPassiveEffectCleanupDuringUnmount is ignored unless runAllPassiveEffectDestroysBeforeCreates is true
Before attempting to land an expiration times refactor, I want to see
if this particular change will impact performance (either positively
or negatively). I will test this with a GK.
This babel transform is a fork of the @babel/plugin-transform-react-jsx transform and is for experimentation purposes only. We don't plan to own this code in the future, and we will upstream this to Babel at some point once we've proven out the concept.
As per the RFC to simplify element creation, we want to add the ability to auto import "react' directly from the babel plugin. This commit updates the babel plugin with two options:
1.) importSource: The React module to import from. Defaults to react.
2.) autoImport: The type of import. Defaults to none.
- none: Does not import React. JSX compiles to React.jsx etc.
- namespace: import * as _react from "react";. JSX compiles to _react.jsx etc.
- default: import _default from "react"; JSX compiles to _default.jsx etc.
- namedExports: import {jsx as _jsx} from "react"; JSX compiles to _jsx etc.
- require: var _react = _interopRequireWildcard(require("react"));. jSX compiles to _react.jsx etc.
namespace, default, and namedExports can only be used when sourceType: module and require can only be used when sourceType: script.
It also adds two pragmas (jsxAutoImport and jsxImportSource) that allow users to specify autoImport and importSource in the docblock.
* 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 section is empty, and imo isn't really helpful in React's changelog. I'm honestly not sure why this is even here? Figured I'd start a discussion with a PR, or we can remove it right now.
