[Fiber] Track SuspendedState on stack instead of global #34486
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This is safer since some calls need this to be closed over anyway. This will let us persist it longer like into the commit phase.
That way we can transfer state from the collection of suspense commit info into the view transition start.
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Stacked on #34481. We currently track the suspended state temporarily with a global which is safe as long as we always read it during a sync pass. However, we sometimes read it in closures and then we have to be carefully to pass the right one since it's possible another commit on a different root has started at that point. This avoids this footgun. Another reason to do this is that I want to read it in `startViewTransition` which is in an async gap after which point it's no longer safe. So I have to pass that through the `commitRoot` bound function. DiffTrain build for [5d49b2b](5d49b2b)
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…nimation (#34500) Stacked on #34486. If we gave up on loading suspensey images for blocking the commit (e.g. due to #34481), we can still block the view transition from committing to allow an animation to include the image from the start. At this point we have more information about the layout so we can include only the images that are within viewport in the calculation which may end up with a different answer. This only applies when we attempt to run an animation (e.g. something mutated inside a `<ViewTransition>` in a Transition). We could attempt a `startViewTransition` if we gave up on the suspensey images just so that we could block it even if no animation would be running. However, this point the screen is frozen and you can no longer have sync updates interrupt so ideally we would have already blocked the commit from happening in the first place. The reason to have two points where we block is that ideally we leave the UI responsive while blocking, which blocking the commit does. In the simple case of all images or a single image being within the viewport, that's favorable. By combining the techniques we only end up freezing the screen in the special case that we had a lot of images added outside the viewport and started an animation with some image inside the viewport (which presumably is about to finish anyway).
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…nimation (#34500) Stacked on #34486. If we gave up on loading suspensey images for blocking the commit (e.g. due to #34481), we can still block the view transition from committing to allow an animation to include the image from the start. At this point we have more information about the layout so we can include only the images that are within viewport in the calculation which may end up with a different answer. This only applies when we attempt to run an animation (e.g. something mutated inside a `<ViewTransition>` in a Transition). We could attempt a `startViewTransition` if we gave up on the suspensey images just so that we could block it even if no animation would be running. However, this point the screen is frozen and you can no longer have sync updates interrupt so ideally we would have already blocked the commit from happening in the first place. The reason to have two points where we block is that ideally we leave the UI responsive while blocking, which blocking the commit does. In the simple case of all images or a single image being within the viewport, that's favorable. By combining the techniques we only end up freezing the screen in the special case that we had a lot of images added outside the viewport and started an animation with some image inside the viewport (which presumably is about to finish anyway). DiffTrain build for [348a4e2](348a4e2)
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…nimation (#34500) Stacked on #34486. If we gave up on loading suspensey images for blocking the commit (e.g. due to #34481), we can still block the view transition from committing to allow an animation to include the image from the start. At this point we have more information about the layout so we can include only the images that are within viewport in the calculation which may end up with a different answer. This only applies when we attempt to run an animation (e.g. something mutated inside a `<ViewTransition>` in a Transition). We could attempt a `startViewTransition` if we gave up on the suspensey images just so that we could block it even if no animation would be running. However, this point the screen is frozen and you can no longer have sync updates interrupt so ideally we would have already blocked the commit from happening in the first place. The reason to have two points where we block is that ideally we leave the UI responsive while blocking, which blocking the commit does. In the simple case of all images or a single image being within the viewport, that's favorable. By combining the techniques we only end up freezing the screen in the special case that we had a lot of images added outside the viewport and started an animation with some image inside the viewport (which presumably is about to finish anyway). DiffTrain build for [348a4e2](348a4e2)
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…nimation (facebook#34500) Stacked on facebook#34486. If we gave up on loading suspensey images for blocking the commit (e.g. due to facebook#34481), we can still block the view transition from committing to allow an animation to include the image from the start. At this point we have more information about the layout so we can include only the images that are within viewport in the calculation which may end up with a different answer. This only applies when we attempt to run an animation (e.g. something mutated inside a `<ViewTransition>` in a Transition). We could attempt a `startViewTransition` if we gave up on the suspensey images just so that we could block it even if no animation would be running. However, this point the screen is frozen and you can no longer have sync updates interrupt so ideally we would have already blocked the commit from happening in the first place. The reason to have two points where we block is that ideally we leave the UI responsive while blocking, which blocking the commit does. In the simple case of all images or a single image being within the viewport, that's favorable. By combining the techniques we only end up freezing the screen in the special case that we had a lot of images added outside the viewport and started an animation with some image inside the viewport (which presumably is about to finish anyway). DiffTrain build for [348a4e2](facebook@348a4e2)
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…nimation (facebook#34500) Stacked on facebook#34486. If we gave up on loading suspensey images for blocking the commit (e.g. due to facebook#34481), we can still block the view transition from committing to allow an animation to include the image from the start. At this point we have more information about the layout so we can include only the images that are within viewport in the calculation which may end up with a different answer. This only applies when we attempt to run an animation (e.g. something mutated inside a `<ViewTransition>` in a Transition). We could attempt a `startViewTransition` if we gave up on the suspensey images just so that we could block it even if no animation would be running. However, this point the screen is frozen and you can no longer have sync updates interrupt so ideally we would have already blocked the commit from happening in the first place. The reason to have two points where we block is that ideally we leave the UI responsive while blocking, which blocking the commit does. In the simple case of all images or a single image being within the viewport, that's favorable. By combining the techniques we only end up freezing the screen in the special case that we had a lot of images added outside the viewport and started an animation with some image inside the viewport (which presumably is about to finish anyway). DiffTrain build for [348a4e2](facebook@348a4e2)
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Stacked on #34481.
We currently track the suspended state temporarily with a global which is safe as long as we always read it during a sync pass. However, we sometimes read it in closures and then we have to be carefully to pass the right one since it's possible another commit on a different root has started at that point. This avoids this footgun.
Another reason to do this is that I want to read it in
startViewTransitionwhich is in an async gap after which point it's no longer safe. So I have to pass that through thecommitRootbound function.