* Refactor ReactDebugCurrentFiber to use named exports
This makes the difference between it and ReactFiberCurrentFrame a bit clearer.
ReactDebugCurrentFiber is Fiber's own implementation.
ReactFiberCurrentFrame is the thing that holds a reference to the current implementation and delegates to it.
* Unify ReactFiberComponentTreeHook and ReactDebugCurrentFiber
Conceptually they're very related.
ReactFiberComponentTreeHook contains implementation details of reading Fiber's stack (both in DEV and PROD).
ReactDebugCurrentFiber contained a reference to the current fiber, and used the above utility.
It was confusing when to use which one. Colocating them makes it clearer what you could do with each method.
In the future, the plan is to stop using these methods explicitly in most places, and instead delegate to a warning system that includes stacks automatically. This change makes future refactorings simpler by colocating related logic.
* Rename methods to better reflect their meanings
Clarify which are DEV or PROD-only.
Clarify which can return null.
I believe the "work in progress only" was a mistake. I introduced it because I wasn't sure what guarantees we have around .return. But we know for sure that following a .return chain gives us an accurate stack even if we get into WIP trees because we don't have reparenting. So it's fine to relax that naming.
* Rename ReactDebugCurrentFiber -> ReactCurrentFiber
It's not completely DEV-only anymore.
Individual methods already specify whether they work in DEV or PROD in their names.
An infinite update loop can occur when an update is scheduled inside a
lifecycle method, which causes a re-render, which schedules another
update, and so on. Before the Fiber rewrite, this scenario resulted in a
stack overflow.
Because Fiber does not use the JavaScript stack, we maintain our own
counter to track the number of nested, synchronous updates. We throw an
error if the limit is exceeded.
The nested update limit is currently 1000. I chose this number
arbitrarily, certain that there was no valid reason for a component to
schedule so many synchronous re-renders.
I think we can go much lower. This commit decreases the limit to 50. I
believe this is still comfortably above the reasonable number of
synchronous re-renders a component may perform.
This will make it easier for developers to debug infinite update bugs
when they occur.
A recent change to the scheduler caused a regression when scheduling
many updates within a single batch. Added a test case that would
have caught this.
This is an unobservable change to all but the (under development) DevTools Profiler plugin. It is being done so that the plugin can safely feature detect a version of React that supports it. The profiler API has existed since the 16.4.0 release, but it did not support the DevTools plugin prior to PR #13058.
Side note: I am not a big fan of the term "base duration". Both it and "actual duration" are kind of awkward and vague. If anyone has suggestions for better names– this is the best time to bikeshed about them.
* Reset ReactProfilerTimer's DEV-only Fiber stack after an error
* Added ReactNoop functionality to error during "complete" phase
* Added failing profiler stack unwinding test
* Potential fix for unwinding time bug
* Renamed test
* Don't record time until complete phase succeeds. Simplifies unwinding.
* Expanded ReactProfilerDevToolsIntegration-test coverage a bit
* Added unstable_flushWithoutCommitting method to noop renderer
* Added failing multi-root/batch test to ReactProfiler-test
* Beefed up tests a bit and added some TODOs
* Profiler timer differentiates between batched commits and in-progress async work
This was a two-part change:
1) Don't count time spent working on a batched commit against yielded async work.
2) Don't assert an empty stack after processing a batched commit (because there may be yielded async work)
This is kind of a hacky solution, and may have problems that I haven't thought of yet. I need to commit this so I can mentally clock out for a bit without worrying about it. I will think about it more when I'm back from PTO. In the meanwhile, input is welcome.
* Removed TODO
* Replaced FiberRoot map with boolean
* Removed unnecessary whitespace edit
Changed the API to match what we've been using in our latest discussions.
Our tentative plans are for <Placeholder> to automatically hide the timed-out
children, instead of removing them, so their state is not lost. This part is
not yet implemented. We'll likely have a lower level API that does not include
the hiding behavior. This is also not yet implemented.
We can support components that suspend outside of an async mode tree
by immediately committing their placeholders.
In strict mode, the Timeout acts effectively like an error boundary.
Within a single render pass, we unwind to the nearest Timeout and
re-render the placeholder view.
Outside of strict mode, it's not safe to unwind and re-render the
siblings without committing. (Technically, this is true of error
boundaries, too, though probably not a huge deal, since we don't support
using error boundaries for control flow (yet, at least)). We need to be
clever. What we do is pretend the suspended component rendered null.*
There's no unwinding. The siblings commit like normal.
Then, in the commit phase, schedule an update on the Timeout to
synchronously re-render the placeholder. Although this requires an extra
commit, it will not be observable. And because the siblings were not
blocked from committing, they don't have to be strict mode compatible.
Another caveat is that if a component suspends during an async render,
but it's captured by a non-async Timeout, we need to revert to sync
mode. In other words, if any non-async component renders, the entire
tree must complete and commit without yielding.
* The downside of rendering null is that the existing children will be
deleted. We should hide them instead. I'll work on this in a follow-up.
* 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.
* Fix crash during server render.
setTimeout and clearTimeout may not be available in some server-render environments (such as ChakraCore in React.NET), and loading ReactScheduler.js will cause a crash unless the existence of the variables are checked via a typeof comparison.
https://github.com/reactjs/React.NET/issues/555
The crash did not occur in 16.4.0, and the change appears to have been introduced here: https://github.com/facebook/react/pull/12931/files#diff-bbebc3357e1fb99ab13ad796e04b69a6L47
I tested this by using yarn link and running it with a local copy of React.NET. I am unsure the best way to unit test this change, since assigning null to `setTimeout` causes an immediate crash within the Node REPL.
* Fix flow errors and log warning if setTimeout / clearTimeout are
not defined / not a function.
* Use invariant to assert setTimeout / clearTimeout are functions
* Remove use of invariant
* Explain
* Add fixture test for schedule running when tab is backgrounded
**what is the change?:**
Just adding a test to the fixture, where we can easily see whether
scheduled callbacks are called after switching away from the fixture
tab.
**why make this change?:**
We are about to fix the schedule module so that it still runs even when
the tab is in the backround.
**test plan:**
Manually tested the fixture, verified that it works as expected and
right now callbacks are not called when the tab is in the background.
**issue:**
Internal task T30754186
* Fall back to 'setTimeout' when 'requestAnimationFrame' is not called
**what is the change?:**
If 'requestAnimationFrame' is not called for 100ms we fall back to
'setTimeout' to schedule the postmessage.
**why make this change?:**
When you start loading a page, and then switch tabs,
'requestAnimationFrame' is throttled or not called until you come back
to that tab. That means React's rendering, any any other scheduled work,
are paused.
Users expect the page to continue loading, and rendering is part of the
page load in a React app. So we need to continue calling callbacks.
**test plan:**
Manually tested using the new fixture test, observed that the callbacks
were called while switched to another tab. They were called more
slowly, but that seems like a reasonable thing.
**issue:**
Internal task T30754186
* make arguments more explicit
* Fixes children when using dangerouslySetInnerHtml in a selected <option>
This fixes an inadvertent cast of undefined children to an empty string when creating an option tag that will be selected:
```
<select defaultValue="test">
<option value='test' dangerouslySetInnerHTML={{ __html: '‏ test'}} />
</select>
```
This causes an invariant error because both children and dangerouslySetInnerHTML are set.
* PR fix and new ReactDOMServerIntegrationForms test
* Account for null case
* Combine test cases into single test
* Add tests for failure cases
* Fix lint
* react-test-renderer injects itself into DevTools if present
* Fibers are always opted into ProfileMode if DevTools is present
* Added simple test for DevTools + always profiling behavior
* Do not add additional work to a batch that is already rendering.
Otherwise, the part of the tree that hasn't rendered yet will receive
the latest state, but the already rendered part will show the state
as it was before the intervening update.
* Reduce non-helpfulness of comments
Expiration times are computed by adding to the current time (the start
time). However, if two updates are scheduled within the same event, we
should treat their start times as simultaneous, even if the actual clock
time has advanced between the first and second call.
In other words, because expiration times determine how updates are
batched, we want all updates of like priority that occur within the same
event to receive the same expiration time. Otherwise we get tearing.
We keep track of two separate times: the current "renderer" time and the
current "scheduler" time. The renderer time can be updated whenever; it
only exists to minimize the calls performance.now.
But the scheduler time can only be updated if there's no pending work,
or if we know for certain that we're not in the middle of an event.
* 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
In async mode, events are interleaved with rendering. If one of those
events mutates state that is later accessed during render, it can lead
to inconsistencies/tearing.
Restarting the render from the root is often sufficient to fix the
inconsistency. We'll flush the restart synchronously to prevent yet
another mutation from happening during an interleaved event.
We'll only restart during an async render. Sync renders are already
sync, so there's no benefit in restarting. (Unless a mutation happens
during the render phase, but we don't support that.)
* onFatal, onComplete, onSuspend, onYield
For every call to renderRoot, one of onFatal, onComplete, onSuspend,
and onYield is called upon exiting. We use these in lieu of returning a
tuple. I've also chosen not to inline them into renderRoot because these
will eventually be lifted into the renderer.
* Suspended high pri work forces lower priority work to expire early
If an error is thrown, and there is lower priority pending work, we
retry at the lower priority. The lower priority work should expire
at the same time at which the high priority work would have expired.
Effectively, this increases the priority of the low priority work.
Simple example: If an error is thrown during a synchronous render, and
there's an async update, the async update should flush synchronously in
case it's able to fix the error. I've added a unit test for
this scenario.
User provided timeouts should have the same behavior, but I'll leave
that for a future PR.
* Add isUsingKoreanIME function to check if a composition event was triggered by Korean IME
* Add Korean IME check alongside useFallbackCompositionData and disable fallback mode with Korean IME
Dan Abramov
Brian Vaughn
Brandon Dail
Andrew Clark
Chang Yan
XuMM_12
Rouven Weßling
Toru Kobayashi
Joseph Lin
Sebastian Markbåge
Hilbrand Bouwkamp
Rauno Freiberg
Jason Williams
Dustin Masters
Flarnie Marchan
Michael Ridgway
Nathan Quarles
Crux