| 1 | /** |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * |
| 4 | * This source code is licensed under the MIT license found in the |
| 5 | * LICENSE file in the root directory of this source tree. |
| 6 | * |
| 7 | * @flow |
| 8 | */ |
| 9 | |
| 10 | import type {Fiber} from './ReactInternalTypes'; |
| 11 | import type {StackCursor} from './ReactFiberStack'; |
| 12 | import type {Lanes} from './ReactFiberLane'; |
| 13 | |
| 14 | import {createCursor, push, pop} from './ReactFiberStack'; |
| 15 | |
| 16 | import { |
| 17 | getEntangledRenderLanes, |
| 18 | setEntangledRenderLanes, |
| 19 | } from './ReactFiberWorkLoop'; |
| 20 | import {NoLanes, mergeLanes} from './ReactFiberLane'; |
| 21 | |
| 22 | // TODO: Remove `renderLanes` context in favor of hidden context |
| 23 | type HiddenContext = { |
| 24 | // Represents the lanes that must be included when processing updates in |
| 25 | // order to reveal the hidden content. |
| 26 | // TODO: Remove `subtreeLanes` context from work loop in favor of this one. |
| 27 | baseLanes: number, |
| 28 | ... |
| 29 | }; |
| 30 | |
| 31 | // TODO: This isn't being used yet, but it's intended to replace the |
| 32 | // InvisibleParentContext that is currently managed by SuspenseContext. |
| 33 | export const currentTreeHiddenStackCursor: StackCursor<HiddenContext | null> = |
| 34 | createCursor(null); |
| 35 | export const prevEntangledRenderLanesCursor: StackCursor<Lanes> = |
| 36 | createCursor(NoLanes); |
| 37 | |
| 38 | export function pushHiddenContext(fiber: Fiber, context: HiddenContext): void { |
| 39 | const prevEntangledRenderLanes = getEntangledRenderLanes(); |
| 40 | push(prevEntangledRenderLanesCursor, prevEntangledRenderLanes, fiber); |
| 41 | push(currentTreeHiddenStackCursor, context, fiber); |
| 42 | |
| 43 | // When rendering a subtree that's currently hidden, we must include all |
| 44 | // lanes that would have rendered if the hidden subtree hadn't been deferred. |
| 45 | // That is, in order to reveal content from hidden -> visible, we must commit |
| 46 | // all the updates that we skipped when we originally hid the tree. |
| 47 | setEntangledRenderLanes( |
| 48 | mergeLanes(prevEntangledRenderLanes, context.baseLanes), |
| 49 | ); |
| 50 | } |
| 51 | |
| 52 | export function reuseHiddenContextOnStack(fiber: Fiber): void { |
| 53 | // This subtree is not currently hidden, so we don't need to add any lanes |
| 54 | // to the render lanes. But we still need to push something to avoid a |
| 55 | // context mismatch. Reuse the existing context on the stack. |
| 56 | push(prevEntangledRenderLanesCursor, getEntangledRenderLanes(), fiber); |
| 57 | push( |
| 58 | currentTreeHiddenStackCursor, |
| 59 | currentTreeHiddenStackCursor.current, |
| 60 | fiber, |
| 61 | ); |
| 62 | } |
| 63 | |
| 64 | export function popHiddenContext(fiber: Fiber): void { |
| 65 | // Restore the previous render lanes from the stack |
| 66 | setEntangledRenderLanes(prevEntangledRenderLanesCursor.current); |
| 67 | |
| 68 | pop(currentTreeHiddenStackCursor, fiber); |
| 69 | pop(prevEntangledRenderLanesCursor, fiber); |
| 70 | } |
| 71 | |
| 72 | export function isCurrentTreeHidden(): boolean { |
| 73 | return currentTreeHiddenStackCursor.current !== null; |
| 74 | } |