* 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.
useMutableSource hook
useMutableSource() enables React components to safely and efficiently read from a mutable external source in Concurrent Mode. The API will detect mutations that occur during a render to avoid tearing and it will automatically schedule updates when the source is mutated.
RFC: reactjs/rfcs#147
* 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.
* Lazify Blocks
Blocks now initialize lazily.
* Initialize Blocks eagerly in ChildFiber
This is for the case when it's a new Block that hasn't yet initialized.
We need to first initialize it to see what "render function" it resolves
to so that we can use that in our comparison.
* Remove extra import type line
In CI, we run our test suite against multiple build configurations. For
example, we run our tests in both dev and prod, and in both the
experimental and stable release channels. This is to prevent accidental
deviations in behavior between the different builds. If there's an
intentional deviation in behavior, the test author must account
for them.
However, we currently don't run tests against the www builds. That's
a problem, because it's common for features to land in www before they
land anywhere else, including the experimental release channel.
Typically we do this so we can gradually roll out the feature behind
a flag before deciding to enable it.
The way we test those features today is by mutating the
`shared/ReactFeatureFlags` module. There are a few downsides to this
approach, though. The flag is only overridden for the specific tests or
test suites where you apply the override. But usually what you want is
to run *all* tests with the flag enabled, to protect against unexpected
regressions.
Also, mutating the feature flags module only works when running the
tests against source, not against the final build artifacts, because the
ReactFeatureFlags module is inlined by the build script.
Instead, we should run the test suite against the www configuration,
just like we do for prod, experimental, and so on. I've added a new
command, `yarn test-www`. It automatically runs in CI.
Some of the www feature flags are dynamic; that is, they depend on
a runtime condition (i.e. a GK). These flags are imported from an
external module that lives in www. Those flags will be enabled for some
clients and disabled for others, so we should run the tests against
*both* modes.
So I've added a new global `__VARIANT__`, and a new test command `yarn
test-www-variant`. `__VARIANT__` is set to false by default; when
running `test-www-variant`, it's set to true.
If we were going for *really* comprehensive coverage, we would run the
tests against every possible configuration of feature flags: 2 ^
numberOfFlags total combinations. That's not practical, though, so
instead we only run against two combinations: once with `__VARIANT__`
set to `true`, and once with it set to `false`. We generally assume that
flags can be toggled independently, so in practice this should
be enough.
You can also refer to `__VARIANT__` in tests to detect which mode you're
running in. Or, you can import `shared/ReactFeatureFlags` and read the
specific flag you can about. However, we should stop mutating that
module going forward. Treat it as read-only.
In this commit, I have only setup the www tests to run against source.
I'll leave running against build for a follow up.
Many of our tests currently assume they run only in the default
configuration, and break when certain flags are toggled. Rather than fix
these all up front, I've hard-coded the relevant flags to the default
values. We can incrementally migrate those tests later.
* Implemented Profiler onCommit() and onPostCommit() hooks
* Added enableProfilerCommitHooks feature flag for commit hooks
* Moved onCommit and onPassiveCommit behind separate feature flag
* Revert "Revert "feat: honor displayName of context types (#18035)" (#18223)"
This reverts commit 3ee812e6b6.
* Add warning of displayName is set on the consumer
* dedupe warning
* This type is all wrong and nothing cares because it's all any
* Refine Flow types of Lazy Components
We can type each condition.
* Remove _ctor field from Lazy components
This field is not needed because it's only used before we've initialized,
and we don't have anything else to store before we've initialized.
* Check for _ctor in case it's an older isomorphic that created it
We try not to break across minors but it's no guarantee.
* Move types and constants from shared to isomorphic
The "react" package owns the data structure of the Lazy component. It
creates it and decides how any downstream renderer may use it.
* Move constants to shared
Apparently we can't depend on react/src/ because the whole package is
considered "external" as far as rollup is concerned.
* Added missing @flow pragma to React.js
* Fixed useContext() return type definition
* Fixed previously masked Flow errors in DevTools and react-interactions packages
* Added displayName to internal Context Flow type
* Removed Flow generic annotations for createResponder
This seems to cause a parsing error. (Not sure why.) The API is deprecated anyway so I'm being lazy for now and just adding a .
* 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.
* 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.
* 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"
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.
* 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.
* 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.
* Flush useEffect clean up functions in the passive effects phase
This is a change in behavior that may cause broken product code, so it has been added behind a killswitch (deferPassiveEffectCleanupDuringUnmount)
* Avoid scheduling unnecessary callbacks for cleanup effects
Updated enqueuePendingPassiveEffectDestroyFn() to check rootDoesHavePassiveEffects before scheduling a new callback. This way we'll only schedule (at most) one.
* Updated newly added test for added clarity.
* Cleaned up hooks effect tags
We previously used separate Mount* and Unmount* tags to track hooks work for each phase (snapshot, mutation, layout, and passive). This was somewhat complicated to trace through and there were man tag types we never even used (e.g. UnmountLayout, MountMutation, UnmountSnapshot). In addition to this, it left passive and layout hooks looking the same after renders without changed dependencies, which meant we were unable to reliably defer passive effect destroy functions until after the commit phase.
This commit reduces the effect tag types to only include Layout and Passive and differentiates between work and no-work with an HasEffect flag.
* Disabled deferred passive effects flushing in OSS builds for now
* Split up unmount and mount effects list traversal
* 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
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