* Add tail="collapsed" option
* Fix issue with tail exceeding the CPU time limit
We used to assume that this didn't suspend but this branch happens in
both cases. This fixes it so that we first check if we suspended.
Now we can fix the tail so that it always render an additional fallback
in this scenario.
* added flush sync test
* added code to run flushSync with ImmediatePriority
* added code to run flushSync with ImmediatePriority
* fixed flow error
* fixed flow error
* Add a bunch of optimizations to SuspenseList
We now are able to bail out of reconciliation and splitting out the tail
during deep updates that hasn't changed the child props. This only
works while the list wasn't suspended before.
I also moved the second render of the "head" to the complete phase. This
cleans it up a bit for the tail collapsing PR.
For this second pass I also use a new technique of resetting the child
Fibers for the second pass. This is effectively a fast path to avoid
reconciling the children against props again.
* Move to didSuspend from SuspenseListState to the effectTag
The effectTag now tracks whether the previous commit was suspended.
This frees up SuspenseListState to be render-phase only state.
We use null to mean the default "independent" mode.
* Rename to SuspenseListState to SuspenseListRenderState
* Reuse SuspenseListRenderState across render passes
* Add optimization to bail out of scanning children if they can't be suspended
This optimized the deep update case or initial render without anything
suspending.
We have some information available to us that tell us if nothing has
suspended in the past and nothing has suspended this render pass.
This also fixes a bug where we didn't tag the previous render as having
suspended boundaries if we didn't need to force a rerender.
* rm printChildren
oops
* Slightly improve performance of hydration.
Avoid loading nodeType and data couple times from the same node in a row,
but instead load them only once, which will help engines to run this code
faster, especially during startup of the application. The general approach
is still not ideal, since hydrating this way forces the browser engine
to materialize JavaScript wrapper objects for all DOM nodes, even if they
are not interesting to hydration itself.
* Fix condition for COMMENT_NODEs.
* Improve general code readability
Preemptively update tests wrt 'parser' requiring an absolute
path rather than a package name, even though the project is
still using ESLint 4.
Fixes#15971
* use toWarnDev for dom fixture tests
forks toWarnDev from root into fixture/dom, updates tes tests to use it
* disable act() warnings for react-art()
- For 'secondary' renderers like react-act, we don't want to fire missing act() warnings; the wrapping renderer will fire warnings anyway, and when it flushes, it flushes effects *across* renderers.
- I could have used isPrimaryRenderer as the flag, but this is marked as false for react-test-renderer, and we *do* want the warning to fire for it. Hence a new flag.
* add missing dependency `art` to fixtures/dom
* Retry failed roots on refresh
* Don't prevent retry after error -> render(null) special case
The check wasn't very resilient because in Concurrent Mode it looks like we can get further follow-up commits even if we captured an error. So we can't reliably distinguish the case where after an error you _manually_ rendered null.
Retrying on an edit after a tree failed _and_ you rendered null in the same tree seems fine. It's also very unlikely a pattern like this actually exists in the wild.
* warn if passive effects get queued outside of an act() call
While the code itself isn't much (it adds the warning to mountEffect() and updateEffect() in ReactFiberHooks), it does change a lot of our tests. We follow a bad-ish pattern here, which is doing asserts inside act() scopes, but it makes sense for *us* because we're testing intermediate states, and we're manually flush/yield what we need in these tests.
This commit has one last failing test. Working on it.
* pass lint
* pass failing test, fixes another
- a test was failing in ReactDOMServerIntegrationHooks while testing an effect; the behaviour of yields was different from browser and server when wrapped with act(). further, because of how we initialized modules, act() around renders wasn't working corrrectly. solved by passing in ReactTestUtils in initModules, and checking on the finally yielded values in the specific test.
- in ReactUpdates, while testing an infinite recursion detection, the test needed to be wrapped in an act(), which would have caused the recusrsion error to throw. solived by rethrowing the error from inside the act().
* pass ReactDOMServerSuspense
* stray todo
* a better message, consistent with the state update one.
* [Scheduler] requestPaint
Signals to Scheduler that the browser needs to paint the screen. React
will call it in the commit phase. Scheduler will yield at the end of
the current frame, even if there is no pending input.
When `isInputPending` is not available, this has no effect, because we
yield at the end of every frame regardless.
React will call `requestPaint` in the commit phase as long as there's at
least one effect. We could choose not to call it if none of the effects
are DOM mutations, but this is so rare that it doesn't seem worthwhile
to bother checking.
* Fall back gracefully if requestPaint is missing
At the end of each frame, Scheduler yields control of the main thread so
the browser can execute important tasks; most importantly, painting the
screen and responding to user input. There's some overhead involved in
regaining control of the main thread, so we'd like to yield as
infrequently as possible to keep the UI responsive.
The reason we yield on every frame is because there's no way for us to
know whether we're blocking user input.
`isInputPending` is an experimental browser API that gives us this
information. It tells us whether there's a pending user input, which
also means it tells us if there's *not* a pending user input. We can use
this signal to decide whether it's OK not to yield.
There's a max frame length after which we'll yield regardless, as a
precaution against blocking non-input tasks that we don't know about.
* Expire rendering the tail of SuspenseList after a timeout
This is the first Suspense feature that isn't actually dependent on IO.
The thinking here is that it's normal for a SuspenseList to show loading
states, and it'll be designed to handle it one at a time.
However, sometimes there are lists with really big items that take a long
time to CPU render. Since data can become available as we do that, it is
likely that we have all the data and become CPU bound.
In that case, the list would naively just render until the end and then
display all items at once. I think that's actually what you want for fast
lists. However, for slow ones (like News Feed), you're better off showing
a few rows at a time.
It's not necessarily one at a time because if you can do many in a short
period of time and fit them all on the screen, then it's better to do them
all at once than pop them in one at a time very quickly.
Therefore, I use a heuristic of trying to render as many rows as I can in
500ms before giving up.
This timer starts before the first row of the tail and we only check it
after. This ensures that we always make a little progress each attempt.
An alternative approach could be to start the time before doing the head
of the list but we don't want that being slow prevent us from making
further progress.
Currently, I disable this optimization at Never priority because there's
nothing intermediate that becomes visible anyway.
* Fix tracing through a SuspenseList
This ensures that we can spawn new work during render through arbitrary
priorities.
We'll need this for other features too.
Since each priority can commit separately we need to use an array to
include the current interactions on each priority.
The responder region calculation logic wasn't updating the deactivation region
during the lifetime of an event instance, causing incorrect behaviour when the
current press ends outside the press target and if the press target has moved
since the last time the first-and-only time the deactivation region was
measured.
* Add forwards option
* Add backwards option
* Add comment
* Add customized warning messages for case and typos
* Add some more tests for insertions and updates in start/middle/end
* reset scope depth on synchronous errors
we weren't resetting the acting scope depth on sync errors thrown in the callback. this fixes that.
* typos
* add a test to make sure sync error propagate
* Add SuspenseList component type
* Push SuspenseContext for SuspenseList
* Force Suspense boundaries into their fallback state
In the "together" mode, we do a second render pass that forces the
fallbacks to stay in place, if not all can unsuspend at once.
* Add test
* Transfer thennables to the SuspenseList
This way, we end up retrying the SuspenseList in case the nested boundary
that just suspended doesn't actually get mounted with this set of
thennables. This happens when the second pass renders the fallback
directly without first attempting to render the content.
* Add warning for unsupported displayOrder
* Add tests for nested sibling boundaries and nested lists
* Fix nested SuspenseList forwarding thennables
* Rename displayOrder to revealOrder
Display order has some "display list" connotations making it sound like
a z-index thing.
Reveal indicates that this isn't really about when something gets rendered
or is ready to be rendered. It's about when content that is already there
gets to be revealed.
* Add test for avoided boundaries
* Make SuspenseList a noop in legacy mode
* Use an explicit suspense list state object
This will be used for more things in the directional case.
* Track mounted roots via DevTools Hook
* Add helper utilities to the runtime
These utilities will likely be needed by all module systems, so let's just put them here.
* Wrap more things in __DEV__
* Fix tests to also be DEV-only