## Summary
This PR bumps Flow all the way to the latest 0.245.2.
Most of the suppressions comes from Flow v0.239.0's change to include
undefined in the return of `Array.pop`.
I also enabled `react.custom_jsx_typing=true` and added custom jsx
typing to match the old behavior that `React.createElement` is
effectively any typed. This is necessary since various builtin
components like `React.Fragment` is actually symbol in the React repo
instead of `React.AbstractComponent<...>`. It can be made more accurate
by customizing the `React$CustomJSXFactory` type, but I will leave it to
the React team to decide.
## How did you test this change?
`yarn flow` for all the renderers
- substr is Annex B
- substring silently flips its arguments if they're in the "wrong order", which is confusing
- slice is better than sliced bread (no pun intended) and also it works the same way on Arrays so there's less to remember
---
> I'd be down to just lint and enforce a single form just for the potential compression savings by using a repeated string.
_Originally posted by @sebmarkbage in https://github.com/facebook/react/pull/26663#discussion_r1170455401_
Added an explicit type to all $FlowFixMe suppressions to reduce
over-suppressions of new errors that might be caused on the same lines.
Also removes suppressions that aren't used (e.g. in a `@noflow` file as
they're purely misleading)
Test Plan:
yarn flow-ci
The old version of prettier we were using didn't support the Flow syntax
to access properties in a type using `SomeType['prop']`. This updates
`prettier` and `rollup-plugin-prettier` to the latest versions.
I added the prettier config `arrowParens: "avoid"` to reduce the diff
size as the default has changed in Prettier 2.0. The largest amount of
changes comes from function expressions now having a space. This doesn't
have an option to preserve the old behavior, so we have to update this.
Hermes parser is the preferred parser for Flow code going forward. We
need to upgrade to this parser to support new Flow syntax like function
`this` context type annotations or `ObjectType['prop']` syntax.
Unfortunately, there's quite a few upgrades here to make it work somehow
(dependencies between the changes)
- ~Upgrade `eslint` to `8.*`~ reverted this as the React eslint plugin
tests depend on the older version and there's a [yarn
bug](https://github.com/yarnpkg/yarn/issues/6285) that prevents
`devDependencies` and `peerDependencies` to different versions.
- Remove `eslint-config-fbjs` preset dependency and inline the rules,
imho this makes it a lot clearer what the rules are.
- Remove the turned off `jsx-a11y/*` rules and it's dependency instead
of inlining those from the `fbjs` config.
- Update parser and dependency from `babel-eslint` to `hermes-eslint`.
- `ft-flow/no-unused-expressions` rule replaces `no-unused-expressions`
which now allows standalone type asserts, e.g. `(foo: number);`
- Bunch of globals added to the eslint config
- Disabled `no-redeclare`, seems like the eslint upgrade started making
this more precise and warn against re-defined globals like
`__EXPERIMENTAL__` (in rollup scripts) or `fetch` (when importing fetch
from node-fetch).
- Minor lint fixes like duplicate keys in objects.
* Facebook -> Meta in copyright
rg --files | xargs sed -i 's#Copyright (c) Facebook, Inc. and its affiliates.#Copyright (c) Meta Platforms, Inc. and affiliates.#g'
* Manual tweaks
- method unbinding is no longer supported in Flow for soundness, this added a bunch of suppressions
- Flow now prevents objects to be supertypes of interfaces/classes
ghstack-source-id: d7749cbad8
Pull Request resolved: https://github.com/facebook/react/pull/25412
* Fix infinite loop if unmemoized val passed to uDV
The current implementation of useDeferredValue will spawn a new
render any time the input value is different from the previous one. So
if you pass an unmemoized value (like an inline object), it will never
stop spawning new renders.
The fix is to only defer during an urgent render. If we're already
inside a transition, retry, offscreen, or other non-urgen render, then
we can use the latest value.
* Temporarily disable "long nested update" warning
DevTools' timeline profiler warns if an update inside a layout effect
results in an expensive re-render. However, it misattributes renders
that are spawned from a sync render at lower priority. This affects the
new implementation of useDeferredValue but it would also apply to things
like Offscreen.
It's not obvious to me how to fix this given how DevTools models the
idea of a "nested update" so I'm disabling the warning for now to
unblock the bugfix for useDeferredValue.
Refactor DevTools to record Timeline data (in memory) while profiling. Updated the Profiler UI to import/export Timeline data along with legacy profiler data.
Relates to issue #22529
Until now, DEV and PROFILING builds of React recorded Timeline profiling data using the User Timing API. This commit changes things so that React records this data by calling methods on the DevTools hook. (For now, DevTools still records that data using the User Timing API, to match previous behavior.)
This commit is large but most of it is just moving things around:
* New methods have been added to the DevTools hook (in "backend/profilingHooks") for recording the Timeline performance events.
* Reconciler's "ReactFiberDevToolsHook" has been updated to call these new methods (when they're present).
* User Timing method calls in "SchedulingProfiler" have been moved to DevTools "backend/profilingHooks" (to match previous behavior, for now).
* The old reconciler tests, "SchedulingProfiler-test" and "SchedulingProfilerLabels-test", have been moved into DevTools "TimelineProfiler-test" to ensure behavior didn't change unexpectedly.
* Two new methods have been added to the injected renderer interface: injectProfilingHooks() and getLaneLabelMap().
Relates to #22529.