1641 lines
62 KiB
C++
1641 lines
62 KiB
C++
/*
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* Copyright (c) Meta Platforms, Inc. and affiliates.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*/
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#include "Differentiator.h"
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#include <butter/map.h>
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#include <butter/small_vector.h>
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#include <react/debug/react_native_assert.h>
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#include <react/renderer/core/LayoutableShadowNode.h>
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#include <react/renderer/debug/SystraceSection.h>
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#include <algorithm>
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#include "ShadowView.h"
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#ifdef DEBUG_LOGS_DIFFER
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#include <glog/logging.h>
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#define DEBUG_LOGS_BREADCRUMBS 1
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#define DEBUG_LOGS(code) code
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#else
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#define DEBUG_LOGS(code)
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#endif
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#ifdef DEBUG_LOGS_BREADCRUMBS
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#define BREADCRUMB_TYPE std::string
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#define DIFF_BREADCRUMB(X) (breadcrumb + " - " + std::string(X))
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#define CREATE_DIFF_BREADCRUMB(X) std::to_string(X)
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#else
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enum class NoBreadcrumb {};
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#define BREADCRUMB_TYPE NoBreadcrumb const &
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#define DIFF_BREADCRUMB(X) \
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{}
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#define CREATE_DIFF_BREADCRUMB(X) \
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{}
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#endif
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namespace facebook::react {
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/*
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* Extremely simple and naive implementation of a map.
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* The map is simple but it's optimized for particular constraints that we have
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* here.
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*
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* A regular map implementation (e.g. `std::unordered_map`) has some basic
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* performance guarantees like constant average insertion and lookup complexity.
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* This is nice, but it's *average* complexity measured on a non-trivial amount
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* of data. The regular map is a very complex data structure that using hashing,
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* buckets, multiple comprising operations, multiple allocations and so on.
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*
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* In our particular case, we need a map for `int` to `void *` with a dozen
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* values. In these conditions, nothing can beat a naive implementation using a
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* stack-allocated vector. And this implementation is exactly this: no
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* allocation, no hashing, no complex branching, no buckets, no iterators, no
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* rehashing, no other guarantees. It's crazy limited, unsafe, and performant on
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* a trivial amount of data.
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*
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* Besides that, we also need to optimize for insertion performance (the case
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* where a bunch of views appears on the screen first time); in this
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* implementation, this is as performant as vector `push_back`.
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*/
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template <typename KeyT, typename ValueT, int DefaultSize = 16>
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class TinyMap final {
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public:
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using Pair = std::pair<KeyT, ValueT>;
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using Iterator = Pair *;
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/**
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* This must strictly only be called from outside of this class.
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*/
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inline Iterator begin() {
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// Force a clean so that iterating over this TinyMap doesn't iterate over
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// erased elements. If all elements erased are at the front of the vector,
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// then we don't need to clean.
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cleanVector(erasedAtFront_ != numErased_);
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Iterator it = begin_();
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if (it != nullptr) {
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return it + erasedAtFront_;
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}
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return nullptr;
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}
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inline Iterator end() {
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// `back()` asserts on the vector being non-empty
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if (vector_.empty() || numErased_ == vector_.size()) {
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return nullptr;
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}
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return &vector_.back() + 1;
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}
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inline Iterator find(KeyT key) {
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cleanVector();
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react_native_assert(key != 0);
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if (begin_() == nullptr) {
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return end();
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}
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for (auto it = begin_() + erasedAtFront_; it != end(); it++) {
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if (it->first == key) {
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return it;
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}
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}
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return end();
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}
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inline void insert(Pair pair) {
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react_native_assert(pair.first != 0);
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vector_.push_back(pair);
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}
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inline void erase(Iterator iterator) {
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// Invalidate tag.
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iterator->first = 0;
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if (iterator == begin_() + erasedAtFront_) {
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erasedAtFront_++;
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}
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numErased_++;
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}
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private:
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/**
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* Same as begin() but doesn't call cleanVector at the beginning.
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*/
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inline Iterator begin_() {
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// `front()` asserts on the vector being non-empty
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if (vector_.empty() || vector_.size() == numErased_) {
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return nullptr;
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}
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return &vector_.front();
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}
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/**
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* Remove erased elements from internal vector.
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* We only modify the vector if erased elements are at least half of the
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* vector.
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*/
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inline void cleanVector(bool forceClean = false) {
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if ((numErased_ < (vector_.size() / 2) && !forceClean) || vector_.empty() ||
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numErased_ == 0 || numErased_ == erasedAtFront_) {
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return;
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}
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if (numErased_ == vector_.size()) {
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vector_.clear();
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} else {
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vector_.erase(
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std::remove_if(
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vector_.begin(),
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vector_.end(),
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[](auto const &item) { return item.first == 0; }),
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vector_.end());
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}
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numErased_ = 0;
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erasedAtFront_ = 0;
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}
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butter::small_vector<Pair, DefaultSize> vector_;
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size_t numErased_{0};
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size_t erasedAtFront_{0};
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};
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/*
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* Sorting comparator for `reorderInPlaceIfNeeded`.
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*/
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static bool shouldFirstPairComesBeforeSecondOne(
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ShadowViewNodePair const *lhs,
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ShadowViewNodePair const *rhs) noexcept {
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return lhs->shadowNode->getOrderIndex() < rhs->shadowNode->getOrderIndex();
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}
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/*
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* Reorders pairs in-place based on `orderIndex` using a stable sort algorithm.
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*/
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static void reorderInPlaceIfNeeded(
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ShadowViewNodePair::NonOwningList &pairs) noexcept {
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if (pairs.size() < 2) {
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return;
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}
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auto isReorderNeeded = false;
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for (auto const &pair : pairs) {
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if (pair->shadowNode->getOrderIndex() != 0) {
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isReorderNeeded = true;
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break;
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}
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}
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if (!isReorderNeeded) {
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return;
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}
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std::stable_sort(
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pairs.begin(), pairs.end(), &shouldFirstPairComesBeforeSecondOne);
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}
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static inline bool shadowNodeIsConcrete(ShadowNode const &shadowNode) {
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return shadowNode.getTraits().check(ShadowNodeTraits::Trait::FormsView);
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}
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static void sliceChildShadowNodeViewPairsRecursivelyV2(
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ShadowViewNodePair::NonOwningList &pairList,
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ViewNodePairScope &scope,
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Point layoutOffset,
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ShadowNode const &shadowNode) {
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for (auto const &sharedChildShadowNode : shadowNode.getChildren()) {
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auto &childShadowNode = *sharedChildShadowNode;
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#ifndef ANDROID
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// Temporary disabled on Android because the mounting infrastructure
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// is not fully ready yet.
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if (childShadowNode.getTraits().check(ShadowNodeTraits::Trait::Hidden)) {
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continue;
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}
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#endif
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auto shadowView = ShadowView(childShadowNode);
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auto origin = layoutOffset;
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if (shadowView.layoutMetrics != EmptyLayoutMetrics) {
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origin += shadowView.layoutMetrics.frame.origin;
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shadowView.layoutMetrics.frame.origin += layoutOffset;
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}
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// This might not be a FormsView, or a FormsStackingContext. We let the
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// differ handle removal of flattened views from the Mounting layer and
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// shuffling their children around.
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bool isConcreteView = shadowNodeIsConcrete(childShadowNode);
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bool areChildrenFlattened = !childShadowNode.getTraits().check(
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ShadowNodeTraits::Trait::FormsStackingContext);
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Point storedOrigin = {};
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if (areChildrenFlattened) {
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storedOrigin = origin;
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}
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scope.push_back(
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{shadowView,
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&childShadowNode,
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areChildrenFlattened,
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isConcreteView,
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storedOrigin});
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pairList.push_back(&scope.back());
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if (areChildrenFlattened) {
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sliceChildShadowNodeViewPairsRecursivelyV2(
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pairList, scope, origin, childShadowNode);
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}
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}
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}
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ShadowViewNodePair::NonOwningList sliceChildShadowNodeViewPairsV2(
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ShadowNode const &shadowNode,
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ViewNodePairScope &scope,
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bool allowFlattened,
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Point layoutOffset) {
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auto pairList = ShadowViewNodePair::NonOwningList{};
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if (!shadowNode.getTraits().check(
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ShadowNodeTraits::Trait::FormsStackingContext) &&
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shadowNode.getTraits().check(ShadowNodeTraits::Trait::FormsView) &&
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!allowFlattened) {
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return pairList;
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}
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sliceChildShadowNodeViewPairsRecursivelyV2(
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pairList, scope, layoutOffset, shadowNode);
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// Sorting pairs based on `orderIndex` if needed.
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reorderInPlaceIfNeeded(pairList);
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// Set list and mountIndex for each after reordering
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size_t mountIndex = 0;
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for (auto child : pairList) {
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child->mountIndex = (child->isConcreteView ? mountIndex++ : -1);
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}
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return pairList;
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}
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/**
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* Prefer calling this over `sliceChildShadowNodeViewPairsV2` directly, when
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* possible. This can account for adding parent LayoutMetrics that are
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* important to take into account, but tricky, in (un)flattening cases.
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*/
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static ShadowViewNodePair::NonOwningList
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sliceChildShadowNodeViewPairsFromViewNodePair(
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ShadowViewNodePair const &shadowViewNodePair,
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ViewNodePairScope &scope,
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bool allowFlattened = false) {
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return sliceChildShadowNodeViewPairsV2(
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*shadowViewNodePair.shadowNode,
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scope,
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allowFlattened,
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shadowViewNodePair.contextOrigin);
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}
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/*
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* Before we start to diff, let's make sure all our core data structures are
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* in good shape to deliver the best performance.
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*/
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static_assert(
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std::is_move_constructible<ShadowViewMutation>::value,
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"`ShadowViewMutation` must be `move constructible`.");
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static_assert(
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std::is_move_constructible<ShadowView>::value,
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"`ShadowView` must be `move constructible`.");
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static_assert(
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std::is_move_constructible<ShadowViewNodePair>::value,
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"`ShadowViewNodePair` must be `move constructible`.");
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static_assert(
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std::is_move_constructible<ShadowViewNodePair::NonOwningList>::value,
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"`ShadowViewNodePair::NonOwningList` must be `move constructible`.");
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static_assert(
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std::is_move_assignable<ShadowViewMutation>::value,
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"`ShadowViewMutation` must be `move assignable`.");
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static_assert(
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std::is_move_assignable<ShadowView>::value,
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"`ShadowView` must be `move assignable`.");
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static_assert(
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std::is_move_assignable<ShadowViewNodePair>::value,
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"`ShadowViewNodePair` must be `move assignable`.");
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static_assert(
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std::is_move_assignable<ShadowViewNodePair::NonOwningList>::value,
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"`ShadowViewNodePair::NonOwningList` must be `move assignable`.");
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static void calculateShadowViewMutationsV2(
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ViewNodePairScope &scope,
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ShadowViewMutation::List &mutations,
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ShadowView const &parentShadowView,
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ShadowViewNodePair::NonOwningList &&oldChildPairs,
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ShadowViewNodePair::NonOwningList &&newChildPairs,
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bool isRecursionRedundant = false);
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struct OrderedMutationInstructionContainer {
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ShadowViewMutation::List createMutations{};
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ShadowViewMutation::List deleteMutations{};
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ShadowViewMutation::List insertMutations{};
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ShadowViewMutation::List removeMutations{};
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ShadowViewMutation::List updateMutations{};
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ShadowViewMutation::List downwardMutations{};
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ShadowViewMutation::List destructiveDownwardMutations{};
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};
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static void updateMatchedPairSubtrees(
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ViewNodePairScope &scope,
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OrderedMutationInstructionContainer &mutationContainer,
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TinyMap<Tag, ShadowViewNodePair *> &newRemainingPairs,
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ShadowViewNodePair::NonOwningList &oldChildPairs,
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ShadowView const &parentShadowView,
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ShadowViewNodePair const &oldPair,
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ShadowViewNodePair const &newPair);
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static void updateMatchedPair(
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OrderedMutationInstructionContainer &mutationContainer,
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bool oldNodeFoundInOrder,
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bool newNodeFoundInOrder,
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ShadowView const &parentShadowView,
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ShadowViewNodePair const &oldPair,
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ShadowViewNodePair const &newPair);
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static void calculateShadowViewMutationsFlattener(
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ViewNodePairScope &scope,
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ReparentMode reparentMode,
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OrderedMutationInstructionContainer &mutationContainer,
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ShadowView const &parentShadowView,
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TinyMap<Tag, ShadowViewNodePair *> &unvisitedOtherNodes,
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ShadowViewNodePair const &node,
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TinyMap<Tag, ShadowViewNodePair *> *parentSubVisitedOtherNewNodes = nullptr,
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TinyMap<Tag, ShadowViewNodePair *> *parentSubVisitedOtherOldNodes =
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nullptr);
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/**
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* Updates the subtrees of any matched ShadowViewNodePair. This handles
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* all cases of flattening/unflattening.
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*
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* This may modify data-structures passed to it and owned by the caller,
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* specifically `newRemainingPairs`, and so the caller must also own
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* the ViewNodePairScope used within.
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*/
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static void updateMatchedPairSubtrees(
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ViewNodePairScope &scope,
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OrderedMutationInstructionContainer &mutationContainer,
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TinyMap<Tag, ShadowViewNodePair *> &newRemainingPairs,
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ShadowViewNodePair::NonOwningList &oldChildPairs,
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ShadowView const &parentShadowView,
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ShadowViewNodePair const &oldPair,
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ShadowViewNodePair const &newPair) {
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// Are we flattening or unflattening either one? If node was
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// flattened in both trees, there's no change, just continue.
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if (oldPair.flattened && newPair.flattened) {
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return;
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}
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// We are either flattening or unflattening this node.
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if (oldPair.flattened != newPair.flattened) {
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DEBUG_LOGS({
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LOG(ERROR)
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<< "Differ: flattening or unflattening in updateMatchedPairSubtrees: ["
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<< oldPair.shadowView.tag << "] [" << newPair.shadowView.tag << "] "
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<< oldPair.flattened << " " << newPair.flattened << " with parent: ["
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<< parentShadowView.tag << "]";
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});
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// Flattening
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if (!oldPair.flattened) {
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// Flatten old tree into new list
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// At the end of this loop we still want to know which of these
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// children are visited, so we reuse the `newRemainingPairs`
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// map.
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calculateShadowViewMutationsFlattener(
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scope,
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ReparentMode::Flatten,
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mutationContainer,
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parentShadowView,
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newRemainingPairs,
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oldPair);
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}
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// Unflattening
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else {
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// Construct unvisited nodes map
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auto unvisitedOldChildPairs = TinyMap<Tag, ShadowViewNodePair *>{};
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// We don't know where all the children of oldChildPair are
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// within oldChildPairs, but we know that they're in the same
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// relative order. The reason for this is because of flattening
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// + zIndex: the children could be listed before the parent,
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// interwoven with children from other nodes, etc.
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auto oldFlattenedNodes =
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sliceChildShadowNodeViewPairsFromViewNodePair(oldPair, scope, true);
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for (size_t i = 0, j = 0;
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i < oldChildPairs.size() && j < oldFlattenedNodes.size();
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i++) {
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auto &oldChild = *oldChildPairs[i];
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if (oldChild.shadowView.tag == oldFlattenedNodes[j]->shadowView.tag) {
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unvisitedOldChildPairs.insert({oldChild.shadowView.tag, &oldChild});
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j++;
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}
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}
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// Unflatten old list into new tree
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calculateShadowViewMutationsFlattener(
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scope,
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ReparentMode::Unflatten,
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mutationContainer,
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parentShadowView,
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unvisitedOldChildPairs,
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newPair);
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// If old nodes were not visited, we know that we can delete
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// them now. They will be removed from the hierarchy by the
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// outermost loop of this function.
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// TODO: is this necessary anymore?
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for (auto &oldFlattenedNodePtr : oldFlattenedNodes) {
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auto &oldFlattenedNode = *oldFlattenedNodePtr;
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auto unvisitedOldChildPairIt =
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unvisitedOldChildPairs.find(oldFlattenedNode.shadowView.tag);
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if (unvisitedOldChildPairIt == unvisitedOldChildPairs.end()) {
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// Node was visited - make sure to remove it from
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// "newRemainingPairs" map
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auto newRemainingIt =
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newRemainingPairs.find(oldFlattenedNode.shadowView.tag);
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if (newRemainingIt != newRemainingPairs.end()) {
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newRemainingPairs.erase(newRemainingIt);
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}
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}
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}
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}
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return;
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}
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// Update subtrees if View is not flattened, and if node addresses
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// are not equal
|
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if (oldPair.shadowNode != newPair.shadowNode) {
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ViewNodePairScope innerScope{};
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auto oldGrandChildPairs =
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sliceChildShadowNodeViewPairsFromViewNodePair(oldPair, innerScope);
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auto newGrandChildPairs =
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sliceChildShadowNodeViewPairsFromViewNodePair(newPair, innerScope);
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calculateShadowViewMutationsV2(
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innerScope,
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*(newGrandChildPairs.size()
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? &mutationContainer.downwardMutations
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: &mutationContainer.destructiveDownwardMutations),
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oldPair.shadowView,
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std::move(oldGrandChildPairs),
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std::move(newGrandChildPairs));
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}
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}
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|
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/**
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* Handle updates to a matched node pair, but NOT to their subtrees.
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*
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|
* Here we have (and need) knowledge of whether a node was found during
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* in-order traversal, or out-of-order via a map lookup. Nodes are only REMOVEd
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|
* or INSERTTed when they are encountered via in-order-traversal, to ensure
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* correct ordering of INSERT and REMOVE mutations.
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*/
|
|
static void updateMatchedPair(
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OrderedMutationInstructionContainer &mutationContainer,
|
|
bool oldNodeFoundInOrder,
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bool newNodeFoundInOrder,
|
|
ShadowView const &parentShadowView,
|
|
ShadowViewNodePair const &oldPair,
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ShadowViewNodePair const &newPair) {
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oldPair.otherTreePair = &newPair;
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newPair.otherTreePair = &oldPair;
|
|
|
|
// Check concrete-ness of views
|
|
// Create/Delete and Insert/Remove if necessary
|
|
if (oldPair.isConcreteView != newPair.isConcreteView) {
|
|
if (newPair.isConcreteView) {
|
|
if (newNodeFoundInOrder) {
|
|
mutationContainer.insertMutations.push_back(
|
|
ShadowViewMutation::InsertMutation(
|
|
parentShadowView,
|
|
newPair.shadowView,
|
|
static_cast<int>(newPair.mountIndex)));
|
|
}
|
|
mutationContainer.createMutations.push_back(
|
|
ShadowViewMutation::CreateMutation(newPair.shadowView));
|
|
} else {
|
|
if (oldNodeFoundInOrder) {
|
|
mutationContainer.removeMutations.push_back(
|
|
ShadowViewMutation::RemoveMutation(
|
|
parentShadowView,
|
|
oldPair.shadowView,
|
|
static_cast<int>(oldPair.mountIndex)));
|
|
}
|
|
mutationContainer.deleteMutations.push_back(
|
|
ShadowViewMutation::DeleteMutation(oldPair.shadowView));
|
|
}
|
|
} else if (oldPair.isConcreteView && newPair.isConcreteView) {
|
|
// If we found the old node by traversing, but not the new node,
|
|
// it means that there's some reordering requiring a REMOVE mutation.
|
|
if (oldNodeFoundInOrder && !newNodeFoundInOrder) {
|
|
mutationContainer.removeMutations.push_back(
|
|
ShadowViewMutation::RemoveMutation(
|
|
parentShadowView,
|
|
newPair.shadowView,
|
|
static_cast<int>(oldPair.mountIndex)));
|
|
}
|
|
|
|
// Even if node's children are flattened, it might still be a
|
|
// concrete view. The case where they're different is handled
|
|
// above.
|
|
if (oldPair.shadowView != newPair.shadowView) {
|
|
mutationContainer.updateMutations.push_back(
|
|
ShadowViewMutation::UpdateMutation(
|
|
oldPair.shadowView, newPair.shadowView, parentShadowView));
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Here we flatten or unflatten a subtree, given an unflattened node in either
|
|
* the old or new tree, and a list of flattened nodes in the other tree.
|
|
*
|
|
* For example: if you are Flattening, the node will be in the old tree and
|
|
the
|
|
* list will be from the new tree. If you are Unflattening, the opposite is
|
|
true.
|
|
|
|
* It is currently not possible for ReactJS, and therefore React Native, to
|
|
move
|
|
* a node *from* one parent to another without an entirely new subtree being
|
|
* created. When we "reparent" in React Native here it is only because
|
|
intermediate
|
|
* ShadowNodes/ShadowViews, which *always* exist, are flattened or unflattened
|
|
away.
|
|
* Thus, this algorithm handles the very specialized cases of the tree
|
|
collapsing or
|
|
* expanding vertically in that way.
|
|
|
|
* Sketch of algorithm:
|
|
* 0. Create a map of nodes in the flattened list. This should be done
|
|
*before*
|
|
* calling this function.
|
|
* 1. Traverse the Node Subtree; remove elements from the map as they are
|
|
* visited in the tree.
|
|
* Perform a Remove/Insert depending on if we're flattening or unflattening
|
|
* If Tree node is not in Map/List, perform Delete/Create.
|
|
* 2. Traverse the list.
|
|
* Perform linear remove from the old View, or insert into the new parent
|
|
* View if we're flattening.
|
|
* If a node is in the list but not the map, it means it's been visited and
|
|
* Update has already been
|
|
* performed in the subtree. If it *is* in the map, it means the node is
|
|
not
|
|
* * in the Tree, and should be Deleted/Created
|
|
* **after this function is called**, by the caller.
|
|
*/
|
|
static void calculateShadowViewMutationsFlattener(
|
|
ViewNodePairScope &scope,
|
|
ReparentMode reparentMode,
|
|
OrderedMutationInstructionContainer &mutationContainer,
|
|
ShadowView const &parentShadowView,
|
|
TinyMap<Tag, ShadowViewNodePair *> &unvisitedOtherNodes,
|
|
ShadowViewNodePair const &node,
|
|
TinyMap<Tag, ShadowViewNodePair *> *parentSubVisitedOtherNewNodes,
|
|
TinyMap<Tag, ShadowViewNodePair *> *parentSubVisitedOtherOldNodes) {
|
|
DEBUG_LOGS({
|
|
LOG(ERROR) << "Differ Flattener 1: "
|
|
<< (reparentMode == ReparentMode::Unflatten ? "Unflattening"
|
|
: "Flattening")
|
|
<< " [" << node.shadowView.tag << "]";
|
|
});
|
|
|
|
// Step 1: iterate through entire tree
|
|
ShadowViewNodePair::NonOwningList treeChildren =
|
|
sliceChildShadowNodeViewPairsFromViewNodePair(node, scope);
|
|
|
|
DEBUG_LOGS({
|
|
LOG(ERROR) << "Differ Flattener 1.4: "
|
|
<< (reparentMode == ReparentMode::Unflatten ? "Unflattening"
|
|
: "Flattening")
|
|
<< " [" << node.shadowView.tag << "]";
|
|
LOG(ERROR) << "Differ Flattener Entry: Child Pairs: ";
|
|
std::string strTreeChildPairs;
|
|
for (size_t k = 0; k < treeChildren.size(); k++) {
|
|
strTreeChildPairs.append(std::to_string(treeChildren[k]->shadowView.tag));
|
|
strTreeChildPairs.append(treeChildren[k]->isConcreteView ? "" : "'");
|
|
strTreeChildPairs.append(treeChildren[k]->flattened ? "*" : "");
|
|
strTreeChildPairs.append(", ");
|
|
}
|
|
std::string strListChildPairs;
|
|
for (auto &unvisitedNode : unvisitedOtherNodes) {
|
|
strListChildPairs.append(
|
|
std::to_string(unvisitedNode.second->shadowView.tag));
|
|
strListChildPairs.append(unvisitedNode.second->isConcreteView ? "" : "'");
|
|
strListChildPairs.append(unvisitedNode.second->flattened ? "*" : "");
|
|
strListChildPairs.append(", ");
|
|
}
|
|
LOG(ERROR) << "Differ Flattener Entry: Tree Child Pairs: "
|
|
<< strTreeChildPairs;
|
|
LOG(ERROR) << "Differ Flattener Entry: List Child Pairs: "
|
|
<< strListChildPairs;
|
|
});
|
|
|
|
// Views in other tree that are visited by sub-flattening or
|
|
// sub-unflattening
|
|
TinyMap<Tag, ShadowViewNodePair *> subVisitedOtherNewNodes{};
|
|
TinyMap<Tag, ShadowViewNodePair *> subVisitedOtherOldNodes{};
|
|
auto subVisitedNewMap =
|
|
(parentSubVisitedOtherNewNodes != nullptr ? parentSubVisitedOtherNewNodes
|
|
: &subVisitedOtherNewNodes);
|
|
auto subVisitedOldMap =
|
|
(parentSubVisitedOtherOldNodes != nullptr ? parentSubVisitedOtherOldNodes
|
|
: &subVisitedOtherOldNodes);
|
|
|
|
// Candidates for full tree creation or deletion at the end of this function
|
|
auto deletionCreationCandidatePairs =
|
|
TinyMap<Tag, ShadowViewNodePair const *>{};
|
|
|
|
for (size_t index = 0;
|
|
index < treeChildren.size() && index < treeChildren.size();
|
|
index++) {
|
|
auto &treeChildPair = *treeChildren[index];
|
|
|
|
// Try to find node in other tree
|
|
auto unvisitedIt = unvisitedOtherNodes.find(treeChildPair.shadowView.tag);
|
|
auto subVisitedOtherNewIt =
|
|
(unvisitedIt == unvisitedOtherNodes.end()
|
|
? subVisitedNewMap->find(treeChildPair.shadowView.tag)
|
|
: subVisitedNewMap->end());
|
|
auto subVisitedOtherOldIt =
|
|
(unvisitedIt == unvisitedOtherNodes.end() && subVisitedNewMap->end()
|
|
? subVisitedOldMap->find(treeChildPair.shadowView.tag)
|
|
: subVisitedOldMap->end());
|
|
|
|
bool existsInOtherTree = unvisitedIt != unvisitedOtherNodes.end() ||
|
|
subVisitedOtherNewIt != subVisitedNewMap->end() ||
|
|
subVisitedOtherOldIt != subVisitedOldMap->end();
|
|
|
|
auto otherTreeNodePairPtr =
|
|
(existsInOtherTree
|
|
? (unvisitedIt != unvisitedOtherNodes.end()
|
|
? unvisitedIt->second
|
|
: (subVisitedOtherNewIt != subVisitedNewMap->end()
|
|
? subVisitedOtherNewIt->second
|
|
: subVisitedOtherOldIt->second))
|
|
: nullptr);
|
|
|
|
react_native_assert(
|
|
!existsInOtherTree ||
|
|
(unvisitedIt != unvisitedOtherNodes.end() ||
|
|
subVisitedOtherNewIt != subVisitedNewMap->end() ||
|
|
subVisitedOtherOldIt != subVisitedOldMap->end()));
|
|
react_native_assert(
|
|
unvisitedIt == unvisitedOtherNodes.end() ||
|
|
unvisitedIt->second->shadowView.tag == treeChildPair.shadowView.tag);
|
|
react_native_assert(
|
|
subVisitedOtherNewIt == subVisitedNewMap->end() ||
|
|
subVisitedOtherNewIt->second->shadowView.tag ==
|
|
treeChildPair.shadowView.tag);
|
|
react_native_assert(
|
|
subVisitedOtherOldIt == subVisitedOldMap->end() ||
|
|
subVisitedOtherOldIt->second->shadowView.tag ==
|
|
treeChildPair.shadowView.tag);
|
|
|
|
bool alreadyUpdated = false;
|
|
|
|
// Find in other tree and updated `otherTreePair` pointers
|
|
if (existsInOtherTree) {
|
|
react_native_assert(otherTreeNodePairPtr != nullptr);
|
|
auto newTreeNodePair =
|
|
(reparentMode == ReparentMode::Flatten ? otherTreeNodePairPtr
|
|
: &treeChildPair);
|
|
auto oldTreeNodePair =
|
|
(reparentMode == ReparentMode::Flatten ? &treeChildPair
|
|
: otherTreeNodePairPtr);
|
|
|
|
react_native_assert(newTreeNodePair->shadowView.tag != 0);
|
|
react_native_assert(oldTreeNodePair->shadowView.tag != 0);
|
|
react_native_assert(
|
|
oldTreeNodePair->shadowView.tag == newTreeNodePair->shadowView.tag);
|
|
|
|
alreadyUpdated =
|
|
newTreeNodePair->inOtherTree() || oldTreeNodePair->inOtherTree();
|
|
|
|
// We want to update these values unconditionally. Always do this
|
|
// before hitting any "continue" statements.
|
|
newTreeNodePair->otherTreePair = oldTreeNodePair;
|
|
oldTreeNodePair->otherTreePair = newTreeNodePair;
|
|
react_native_assert(treeChildPair.otherTreePair != nullptr);
|
|
}
|
|
|
|
// Remove all children (non-recursively) of tree being flattened, or
|
|
// insert children into parent tree if they're being unflattened.
|
|
// Caller will take care of the corresponding action in the other tree
|
|
// (caller will handle DELETE case if we REMOVE here; caller will handle
|
|
// CREATE case if we INSERT here).
|
|
if (treeChildPair.isConcreteView) {
|
|
if (reparentMode == ReparentMode::Flatten) {
|
|
// treeChildPair.shadowView represents the "old" view in this case.
|
|
// If there's a "new" view, an UPDATE new -> old will be generated
|
|
// and will be executed before the REMOVE. Thus, we must actually
|
|
// perform a REMOVE (new view) FROM (old index) in this case so that
|
|
// we don't hit asserts in StubViewTree's REMOVE path.
|
|
// We also only do this if the "other" (newer) view is concrete. If
|
|
// it's not concrete, there will be no UPDATE mutation.
|
|
react_native_assert(existsInOtherTree == treeChildPair.inOtherTree());
|
|
if (treeChildPair.inOtherTree() &&
|
|
treeChildPair.otherTreePair->isConcreteView) {
|
|
mutationContainer.removeMutations.push_back(
|
|
ShadowViewMutation::RemoveMutation(
|
|
node.shadowView,
|
|
treeChildPair.otherTreePair->shadowView,
|
|
static_cast<int>(treeChildPair.mountIndex)));
|
|
} else {
|
|
mutationContainer.removeMutations.push_back(
|
|
ShadowViewMutation::RemoveMutation(
|
|
node.shadowView,
|
|
treeChildPair.shadowView,
|
|
static_cast<int>(treeChildPair.mountIndex)));
|
|
}
|
|
} else {
|
|
// treeChildParent represents the "new" version of the node, so
|
|
// we can safely insert it without checking in the other tree
|
|
mutationContainer.insertMutations.push_back(
|
|
ShadowViewMutation::InsertMutation(
|
|
node.shadowView,
|
|
treeChildPair.shadowView,
|
|
static_cast<int>(treeChildPair.mountIndex)));
|
|
}
|
|
}
|
|
|
|
// Find in other tree
|
|
if (existsInOtherTree) {
|
|
react_native_assert(otherTreeNodePairPtr != nullptr);
|
|
auto &otherTreeNodePair = *otherTreeNodePairPtr;
|
|
|
|
auto &newTreeNodePair =
|
|
(reparentMode == ReparentMode::Flatten ? otherTreeNodePair
|
|
: treeChildPair);
|
|
auto &oldTreeNodePair =
|
|
(reparentMode == ReparentMode::Flatten ? treeChildPair
|
|
: otherTreeNodePair);
|
|
|
|
react_native_assert(newTreeNodePair.shadowView.tag != 0);
|
|
react_native_assert(oldTreeNodePair.shadowView.tag != 0);
|
|
react_native_assert(
|
|
oldTreeNodePair.shadowView.tag == newTreeNodePair.shadowView.tag);
|
|
|
|
// If we've already done updates, don't repeat it.
|
|
if (alreadyUpdated) {
|
|
continue;
|
|
}
|
|
|
|
// If we've already done updates on this node, don't repeat.
|
|
if (reparentMode == ReparentMode::Flatten &&
|
|
unvisitedIt == unvisitedOtherNodes.end() &&
|
|
subVisitedOtherOldIt != subVisitedOldMap->end()) {
|
|
continue;
|
|
} else if (
|
|
reparentMode == ReparentMode::Unflatten &&
|
|
unvisitedIt == unvisitedOtherNodes.end() &&
|
|
subVisitedOtherNewIt != subVisitedNewMap->end()) {
|
|
continue;
|
|
}
|
|
|
|
// TODO: compare ShadowNode pointer instead of ShadowView here?
|
|
// Or ShadowNode ptr comparison before comparing ShadowView, to allow for
|
|
// short-circuiting? ShadowView comparison is relatively expensive vs
|
|
// ShadowNode.
|
|
if (newTreeNodePair.shadowView != oldTreeNodePair.shadowView &&
|
|
newTreeNodePair.isConcreteView && oldTreeNodePair.isConcreteView) {
|
|
mutationContainer.updateMutations.push_back(
|
|
ShadowViewMutation::UpdateMutation(
|
|
oldTreeNodePair.shadowView,
|
|
newTreeNodePair.shadowView,
|
|
node.shadowView));
|
|
}
|
|
|
|
// Update children if appropriate.
|
|
if (!oldTreeNodePair.flattened && !newTreeNodePair.flattened) {
|
|
if (oldTreeNodePair.shadowNode != newTreeNodePair.shadowNode) {
|
|
ViewNodePairScope innerScope{};
|
|
calculateShadowViewMutationsV2(
|
|
innerScope,
|
|
mutationContainer.downwardMutations,
|
|
newTreeNodePair.shadowView,
|
|
sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
oldTreeNodePair, innerScope),
|
|
sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
newTreeNodePair, innerScope));
|
|
}
|
|
} else if (oldTreeNodePair.flattened != newTreeNodePair.flattened) {
|
|
// We need to handle one of the children being flattened or
|
|
// unflattened, in the context of a parent flattening or unflattening.
|
|
ReparentMode childReparentMode =
|
|
(oldTreeNodePair.flattened ? ReparentMode::Unflatten
|
|
: ReparentMode::Flatten);
|
|
|
|
// Case 1: child mode is the same as parent.
|
|
// This is a flatten-flatten, or unflatten-unflatten.
|
|
if (childReparentMode == reparentMode) {
|
|
calculateShadowViewMutationsFlattener(
|
|
scope,
|
|
childReparentMode,
|
|
mutationContainer,
|
|
(reparentMode == ReparentMode::Flatten
|
|
? parentShadowView
|
|
: newTreeNodePair.shadowView),
|
|
unvisitedOtherNodes,
|
|
treeChildPair,
|
|
subVisitedNewMap,
|
|
subVisitedOldMap);
|
|
} else {
|
|
// Get flattened nodes from either new or old tree
|
|
auto flattenedNodes = sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
(childReparentMode == ReparentMode::Flatten ? newTreeNodePair
|
|
: oldTreeNodePair),
|
|
scope,
|
|
true);
|
|
// Construct unvisited nodes map
|
|
auto unvisitedRecursiveChildPairs =
|
|
TinyMap<Tag, ShadowViewNodePair *>{};
|
|
for (auto &flattenedNode : flattenedNodes) {
|
|
auto &newChild = *flattenedNode;
|
|
|
|
auto unvisitedOtherNodesIt =
|
|
unvisitedOtherNodes.find(newChild.shadowView.tag);
|
|
if (unvisitedOtherNodesIt != unvisitedOtherNodes.end()) {
|
|
auto unvisitedItPair = *unvisitedOtherNodesIt->second;
|
|
unvisitedRecursiveChildPairs.insert(
|
|
{unvisitedItPair.shadowView.tag, &unvisitedItPair});
|
|
} else {
|
|
unvisitedRecursiveChildPairs.insert(
|
|
{newChild.shadowView.tag, &newChild});
|
|
}
|
|
}
|
|
|
|
// Unflatten parent, flatten child
|
|
if (childReparentMode == ReparentMode::Flatten) {
|
|
// Flatten old tree into new list
|
|
// At the end of this loop we still want to know which of these
|
|
// children are visited, so we reuse the `newRemainingPairs` map.
|
|
calculateShadowViewMutationsFlattener(
|
|
scope,
|
|
ReparentMode::Flatten,
|
|
mutationContainer,
|
|
(reparentMode == ReparentMode::Flatten
|
|
? parentShadowView
|
|
: newTreeNodePair.shadowView),
|
|
unvisitedRecursiveChildPairs,
|
|
oldTreeNodePair,
|
|
subVisitedNewMap,
|
|
subVisitedOldMap);
|
|
}
|
|
// Flatten parent, unflatten child
|
|
else {
|
|
// Unflatten old list into new tree
|
|
calculateShadowViewMutationsFlattener(
|
|
scope,
|
|
ReparentMode::Unflatten,
|
|
mutationContainer,
|
|
(reparentMode == ReparentMode::Flatten
|
|
? parentShadowView
|
|
: newTreeNodePair.shadowView),
|
|
unvisitedRecursiveChildPairs,
|
|
newTreeNodePair,
|
|
subVisitedNewMap,
|
|
subVisitedOldMap);
|
|
|
|
// If old nodes were not visited, we know that we can delete them
|
|
// now. They will be removed from the hierarchy by the outermost
|
|
// loop of this function.
|
|
for (auto &unvisitedRecursiveChildPair :
|
|
unvisitedRecursiveChildPairs) {
|
|
if (unvisitedRecursiveChildPair.first == 0) {
|
|
continue;
|
|
}
|
|
auto &oldFlattenedNode = *unvisitedRecursiveChildPair.second;
|
|
|
|
// Node unvisited - mark the entire subtree for deletion
|
|
if (oldFlattenedNode.isConcreteView &&
|
|
!oldFlattenedNode.inOtherTree()) {
|
|
Tag tag = oldFlattenedNode.shadowView.tag;
|
|
auto deleteCreateIt = deletionCreationCandidatePairs.find(
|
|
oldFlattenedNode.shadowView.tag);
|
|
if (deleteCreateIt == deletionCreationCandidatePairs.end()) {
|
|
deletionCreationCandidatePairs.insert(
|
|
{tag, &oldFlattenedNode});
|
|
}
|
|
} else {
|
|
// Node was visited - make sure to remove it from
|
|
// "newRemainingPairs" map
|
|
auto newRemainingIt =
|
|
unvisitedOtherNodes.find(oldFlattenedNode.shadowView.tag);
|
|
if (newRemainingIt != unvisitedOtherNodes.end()) {
|
|
unvisitedOtherNodes.erase(newRemainingIt);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Mark that node exists in another tree, but only if the tree node is a
|
|
// concrete view. Removing the node from the unvisited list prevents the
|
|
// caller from taking further action on this node, so make sure to
|
|
// delete/create if the Concreteness of the node has changed.
|
|
if (newTreeNodePair.isConcreteView != oldTreeNodePair.isConcreteView) {
|
|
if (newTreeNodePair.isConcreteView) {
|
|
mutationContainer.createMutations.push_back(
|
|
ShadowViewMutation::CreateMutation(newTreeNodePair.shadowView));
|
|
} else {
|
|
mutationContainer.deleteMutations.push_back(
|
|
ShadowViewMutation::DeleteMutation(oldTreeNodePair.shadowView));
|
|
}
|
|
}
|
|
|
|
subVisitedNewMap->insert(
|
|
{newTreeNodePair.shadowView.tag, &newTreeNodePair});
|
|
subVisitedOldMap->insert(
|
|
{oldTreeNodePair.shadowView.tag, &oldTreeNodePair});
|
|
} else {
|
|
// Node does not in exist in other tree.
|
|
if (treeChildPair.isConcreteView && !treeChildPair.inOtherTree()) {
|
|
auto deletionCreationIt =
|
|
deletionCreationCandidatePairs.find(treeChildPair.shadowView.tag);
|
|
if (deletionCreationIt == deletionCreationCandidatePairs.end()) {
|
|
deletionCreationCandidatePairs.insert(
|
|
{treeChildPair.shadowView.tag, &treeChildPair});
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Final step: go through creation/deletion candidates and delete/create
|
|
// subtrees if they were never visited during the execution of the above
|
|
// loop and recursions.
|
|
for (auto &deletionCreationCandidatePair : deletionCreationCandidatePairs) {
|
|
if (deletionCreationCandidatePair.first == 0) {
|
|
continue;
|
|
}
|
|
auto &treeChildPair = *deletionCreationCandidatePair.second;
|
|
|
|
// If node was visited during a flattening/unflattening recursion,
|
|
// and the node in the other tree is concrete, that means it was
|
|
// already created/deleted and we don't need to do that here.
|
|
// It is always the responsibility of the matcher to update subtrees when
|
|
// nodes are matched.
|
|
if (treeChildPair.inOtherTree()) {
|
|
continue;
|
|
}
|
|
|
|
if (reparentMode == ReparentMode::Flatten) {
|
|
mutationContainer.deleteMutations.push_back(
|
|
ShadowViewMutation::DeleteMutation(treeChildPair.shadowView));
|
|
|
|
if (!treeChildPair.flattened) {
|
|
ViewNodePairScope innerScope{};
|
|
calculateShadowViewMutationsV2(
|
|
innerScope,
|
|
mutationContainer.destructiveDownwardMutations,
|
|
treeChildPair.shadowView,
|
|
sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
treeChildPair, innerScope),
|
|
{});
|
|
}
|
|
} else {
|
|
mutationContainer.createMutations.push_back(
|
|
ShadowViewMutation::CreateMutation(treeChildPair.shadowView));
|
|
|
|
if (!treeChildPair.flattened) {
|
|
ViewNodePairScope innerScope{};
|
|
calculateShadowViewMutationsV2(
|
|
innerScope,
|
|
mutationContainer.downwardMutations,
|
|
treeChildPair.shadowView,
|
|
{},
|
|
sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
treeChildPair, innerScope));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void calculateShadowViewMutationsV2(
|
|
ViewNodePairScope &scope,
|
|
ShadowViewMutation::List &mutations,
|
|
ShadowView const &parentShadowView,
|
|
ShadowViewNodePair::NonOwningList &&oldChildPairs,
|
|
ShadowViewNodePair::NonOwningList &&newChildPairs,
|
|
bool isRecursionRedundant) {
|
|
SystraceSection s("Differentiator::calculateShadowViewMutationsV2");
|
|
if (oldChildPairs.empty() && newChildPairs.empty()) {
|
|
return;
|
|
}
|
|
|
|
size_t index = 0;
|
|
|
|
// Lists of mutations
|
|
auto mutationContainer = OrderedMutationInstructionContainer{};
|
|
|
|
DEBUG_LOGS({
|
|
LOG(ERROR) << "Differ Entry: Child Pairs of node: [" << parentShadowView.tag
|
|
<< "]";
|
|
std::string strOldChildPairs;
|
|
for (size_t oldIndex = 0; oldIndex < oldChildPairs.size(); oldIndex++) {
|
|
strOldChildPairs.append(
|
|
std::to_string(oldChildPairs[oldIndex]->shadowView.tag));
|
|
strOldChildPairs.append(
|
|
oldChildPairs[oldIndex]->isConcreteView ? "" : "'");
|
|
strOldChildPairs.append(oldChildPairs[oldIndex]->flattened ? "*" : "");
|
|
strOldChildPairs.append(", ");
|
|
}
|
|
std::string strNewChildPairs;
|
|
for (size_t newIndex = 0; newIndex < newChildPairs.size(); newIndex++) {
|
|
strNewChildPairs.append(
|
|
std::to_string(newChildPairs[newIndex]->shadowView.tag));
|
|
strNewChildPairs.append(
|
|
newChildPairs[newIndex]->isConcreteView ? "" : "'");
|
|
strNewChildPairs.append(newChildPairs[newIndex]->flattened ? "*" : "");
|
|
strNewChildPairs.append(", ");
|
|
}
|
|
LOG(ERROR) << "Differ Entry: Old Child Pairs: " << strOldChildPairs;
|
|
LOG(ERROR) << "Differ Entry: New Child Pairs: " << strNewChildPairs;
|
|
});
|
|
|
|
// Stage 1: Collecting `Update` mutations
|
|
for (index = 0; index < oldChildPairs.size() && index < newChildPairs.size();
|
|
index++) {
|
|
auto &oldChildPair = *oldChildPairs[index];
|
|
auto &newChildPair = *newChildPairs[index];
|
|
|
|
if (oldChildPair.shadowView.tag != newChildPair.shadowView.tag) {
|
|
DEBUG_LOGS({
|
|
LOG(ERROR) << "Differ Branch 1.1: Tags Different: ["
|
|
<< oldChildPair.shadowView.tag << "] ["
|
|
<< newChildPair.shadowView.tag << "]"
|
|
<< " with parent: [" << parentShadowView.tag << "]";
|
|
});
|
|
|
|
// Totally different nodes, updating is impossible.
|
|
break;
|
|
}
|
|
|
|
// If either view was flattened, and that has changed this frame, don't
|
|
// try to update
|
|
if (oldChildPair.flattened != newChildPair.flattened ||
|
|
oldChildPair.isConcreteView != newChildPair.isConcreteView) {
|
|
break;
|
|
}
|
|
|
|
DEBUG_LOGS({
|
|
LOG(ERROR) << "Differ Branch 1.2: Same tags, update and recurse: ["
|
|
<< oldChildPair.shadowView.tag << "]"
|
|
<< (oldChildPair.flattened ? " (flattened)" : "")
|
|
<< (oldChildPair.isConcreteView ? " (concrete)" : "") << "["
|
|
<< newChildPair.shadowView.tag << "]"
|
|
<< (newChildPair.flattened ? " (flattened)" : "")
|
|
<< (newChildPair.isConcreteView ? " (concrete)" : "")
|
|
<< " with parent: [" << parentShadowView.tag << "]";
|
|
});
|
|
|
|
if (newChildPair.isConcreteView &&
|
|
oldChildPair.shadowView != newChildPair.shadowView) {
|
|
mutationContainer.updateMutations.push_back(
|
|
ShadowViewMutation::UpdateMutation(
|
|
oldChildPair.shadowView,
|
|
newChildPair.shadowView,
|
|
parentShadowView));
|
|
}
|
|
|
|
// Recursively update tree if ShadowNode pointers are not equal
|
|
if (!oldChildPair.flattened &&
|
|
oldChildPair.shadowNode != newChildPair.shadowNode) {
|
|
ViewNodePairScope innerScope{};
|
|
auto oldGrandChildPairs = sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
oldChildPair, innerScope);
|
|
auto newGrandChildPairs = sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
newChildPair, innerScope);
|
|
calculateShadowViewMutationsV2(
|
|
innerScope,
|
|
*(newGrandChildPairs.size()
|
|
? &mutationContainer.downwardMutations
|
|
: &mutationContainer.destructiveDownwardMutations),
|
|
oldChildPair.shadowView,
|
|
std::move(oldGrandChildPairs),
|
|
std::move(newGrandChildPairs));
|
|
}
|
|
}
|
|
|
|
size_t lastIndexAfterFirstStage = index;
|
|
|
|
if (index == newChildPairs.size()) {
|
|
// We've reached the end of the new children. We can delete+remove the
|
|
// rest.
|
|
for (; index < oldChildPairs.size(); index++) {
|
|
auto const &oldChildPair = *oldChildPairs[index];
|
|
|
|
DEBUG_LOGS({
|
|
LOG(ERROR) << "Differ Branch 2: Deleting Tag/Tree: ["
|
|
<< oldChildPair.shadowView.tag << "]"
|
|
<< " with parent: [" << parentShadowView.tag << "]";
|
|
});
|
|
|
|
if (!oldChildPair.isConcreteView) {
|
|
continue;
|
|
}
|
|
|
|
// If we take this path, technically the operations and recursion below
|
|
// are redundant. However, some parts of the Fabric ecosystem (namely, as
|
|
// of writing this, LayoutAnimations) rely heavily on getting /explicit/
|
|
// Remove/Delete instructions for every single node in the tree. Thus, we
|
|
// generate the "RemoveDeleteTree" instruction as well as all of the
|
|
// individual Remove/Delete operations below, but we mark those as
|
|
// redundant. The platform layer can then discard the unnecessary
|
|
// instructions. RemoveDeleteTreeMutation is a significant performance
|
|
// improvement but could be improved significantly by eliminating the need
|
|
// for any of the redundant instructions in the future.
|
|
if (ShadowViewMutation::PlatformSupportsRemoveDeleteTreeInstruction &&
|
|
!isRecursionRedundant) {
|
|
mutationContainer.removeMutations.push_back(
|
|
ShadowViewMutation::RemoveDeleteTreeMutation(
|
|
parentShadowView,
|
|
oldChildPair.shadowView,
|
|
static_cast<int>(oldChildPair.mountIndex)));
|
|
}
|
|
|
|
mutationContainer.deleteMutations.push_back(
|
|
ShadowViewMutation::DeleteMutation(
|
|
oldChildPair.shadowView,
|
|
isRecursionRedundant ||
|
|
ShadowViewMutation::
|
|
PlatformSupportsRemoveDeleteTreeInstruction));
|
|
mutationContainer.removeMutations.push_back(
|
|
ShadowViewMutation::RemoveMutation(
|
|
parentShadowView,
|
|
oldChildPair.shadowView,
|
|
static_cast<int>(oldChildPair.mountIndex),
|
|
isRecursionRedundant ||
|
|
ShadowViewMutation::
|
|
PlatformSupportsRemoveDeleteTreeInstruction));
|
|
|
|
// We also have to call the algorithm recursively to clean up the entire
|
|
// subtree starting from the removed view.
|
|
ViewNodePairScope innerScope{};
|
|
calculateShadowViewMutationsV2(
|
|
innerScope,
|
|
mutationContainer.destructiveDownwardMutations,
|
|
oldChildPair.shadowView,
|
|
sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
oldChildPair, innerScope),
|
|
{},
|
|
ShadowViewMutation::PlatformSupportsRemoveDeleteTreeInstruction);
|
|
}
|
|
} else if (index == oldChildPairs.size()) {
|
|
// If we don't have any more existing children we can choose a fast path
|
|
// since the rest will all be create+insert.
|
|
for (; index < newChildPairs.size(); index++) {
|
|
auto const &newChildPair = *newChildPairs[index];
|
|
|
|
DEBUG_LOGS({
|
|
LOG(ERROR) << "Differ Branch 3: Creating Tag/Tree: ["
|
|
<< newChildPair.shadowView.tag << "]"
|
|
<< " with parent: [" << parentShadowView.tag << "]";
|
|
});
|
|
|
|
if (!newChildPair.isConcreteView) {
|
|
continue;
|
|
}
|
|
|
|
mutationContainer.insertMutations.push_back(
|
|
ShadowViewMutation::InsertMutation(
|
|
parentShadowView,
|
|
newChildPair.shadowView,
|
|
static_cast<int>(newChildPair.mountIndex)));
|
|
mutationContainer.createMutations.push_back(
|
|
ShadowViewMutation::CreateMutation(newChildPair.shadowView));
|
|
|
|
ViewNodePairScope innerScope{};
|
|
calculateShadowViewMutationsV2(
|
|
innerScope,
|
|
mutationContainer.downwardMutations,
|
|
newChildPair.shadowView,
|
|
{},
|
|
sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
newChildPair, innerScope));
|
|
}
|
|
} else {
|
|
// Collect map of tags in the new list
|
|
auto newRemainingPairs = TinyMap<Tag, ShadowViewNodePair *>{};
|
|
auto newInsertedPairs = TinyMap<Tag, ShadowViewNodePair *>{};
|
|
auto deletionCandidatePairs = TinyMap<Tag, ShadowViewNodePair const *>{};
|
|
for (; index < newChildPairs.size(); index++) {
|
|
auto &newChildPair = *newChildPairs[index];
|
|
newRemainingPairs.insert({newChildPair.shadowView.tag, &newChildPair});
|
|
}
|
|
|
|
// Walk through both lists at the same time
|
|
// We will perform updates, create+insert, remove+delete, remove+insert
|
|
// (move) here.
|
|
size_t oldIndex = lastIndexAfterFirstStage;
|
|
size_t newIndex = lastIndexAfterFirstStage;
|
|
size_t newSize = newChildPairs.size();
|
|
size_t oldSize = oldChildPairs.size();
|
|
while (newIndex < newSize || oldIndex < oldSize) {
|
|
bool haveNewPair = newIndex < newSize;
|
|
bool haveOldPair = oldIndex < oldSize;
|
|
|
|
// Advance both pointers if pointing to the same element
|
|
if (haveNewPair && haveOldPair) {
|
|
auto const &oldChildPair = *oldChildPairs[oldIndex];
|
|
auto const &newChildPair = *newChildPairs[newIndex];
|
|
|
|
Tag newTag = newChildPair.shadowView.tag;
|
|
Tag oldTag = oldChildPair.shadowView.tag;
|
|
|
|
if (newTag == oldTag) {
|
|
DEBUG_LOGS({
|
|
LOG(ERROR) << "Differ Branch 5: Matched Tags at indices: "
|
|
<< oldIndex << " " << newIndex << ": ["
|
|
<< oldChildPair.shadowView.tag << "]"
|
|
<< (oldChildPair.flattened ? "(flattened)" : "")
|
|
<< (oldChildPair.isConcreteView ? "(concrete)" : "")
|
|
<< " [" << newChildPair.shadowView.tag << "]"
|
|
<< (newChildPair.flattened ? "(flattened)" : "")
|
|
<< (newChildPair.isConcreteView ? "(concrete)" : "")
|
|
<< " with parent: [" << parentShadowView.tag << "]";
|
|
});
|
|
|
|
updateMatchedPair(
|
|
mutationContainer,
|
|
true,
|
|
true,
|
|
parentShadowView,
|
|
oldChildPair,
|
|
newChildPair);
|
|
|
|
updateMatchedPairSubtrees(
|
|
scope,
|
|
mutationContainer,
|
|
newRemainingPairs,
|
|
oldChildPairs,
|
|
parentShadowView,
|
|
oldChildPair,
|
|
newChildPair);
|
|
|
|
newIndex++;
|
|
oldIndex++;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
// We have an old pair, but we either don't have any remaining new pairs
|
|
// or we have one but it's not matched up with the old pair
|
|
if (haveOldPair) {
|
|
auto const &oldChildPair = *oldChildPairs[oldIndex];
|
|
|
|
Tag oldTag = oldChildPair.shadowView.tag;
|
|
|
|
// Was oldTag already inserted? This indicates a reordering, not just
|
|
// a move. The new node has already been inserted, we just need to
|
|
// remove the node from its old position now, and update the node's
|
|
// subtree.
|
|
auto const insertedIt = newInsertedPairs.find(oldTag);
|
|
if (insertedIt != newInsertedPairs.end()) {
|
|
auto const &newChildPair = *insertedIt->second;
|
|
|
|
updateMatchedPair(
|
|
mutationContainer,
|
|
true,
|
|
false,
|
|
parentShadowView,
|
|
oldChildPair,
|
|
newChildPair);
|
|
|
|
updateMatchedPairSubtrees(
|
|
scope,
|
|
mutationContainer,
|
|
newRemainingPairs,
|
|
oldChildPairs,
|
|
parentShadowView,
|
|
oldChildPair,
|
|
newChildPair);
|
|
|
|
newInsertedPairs.erase(insertedIt);
|
|
oldIndex++;
|
|
continue;
|
|
}
|
|
|
|
// Should we generate a delete+remove instruction for the old node?
|
|
// If there's an old node and it's not found in the "new" list, we
|
|
// generate remove+delete for this node and its subtree.
|
|
auto const newIt = newRemainingPairs.find(oldTag);
|
|
if (newIt == newRemainingPairs.end()) {
|
|
oldIndex++;
|
|
|
|
if (!oldChildPair.isConcreteView) {
|
|
continue;
|
|
}
|
|
|
|
// From here, we know the oldChildPair is concrete.
|
|
// We *probably* need to generate a REMOVE mutation (see edge-case
|
|
// notes below).
|
|
|
|
DEBUG_LOGS({
|
|
LOG(ERROR)
|
|
<< "Differ Branch 9: Removing tag that was not reinserted: "
|
|
<< oldIndex << ": [" << oldChildPair.shadowView.tag << "]"
|
|
<< (oldChildPair.flattened ? " (flattened)" : "")
|
|
<< (oldChildPair.isConcreteView ? " (concrete)" : "")
|
|
<< " with parent: [" << parentShadowView.tag << "] "
|
|
<< "node is in other tree? "
|
|
<< (oldChildPair.inOtherTree() ? "yes" : "no");
|
|
});
|
|
|
|
// Edge case: node is not found in `newRemainingPairs`, due to
|
|
// complex (un)flattening cases, but exists in other tree *and* is
|
|
// concrete.
|
|
if (oldChildPair.inOtherTree() &&
|
|
oldChildPair.otherTreePair->isConcreteView) {
|
|
ShadowView const &otherTreeView =
|
|
oldChildPair.otherTreePair->shadowView;
|
|
|
|
// Remove, but remove using the *new* node, since we know
|
|
// an UPDATE mutation from old -> new has been generated.
|
|
// Practically this shouldn't matter for most mounting layer
|
|
// implementations, but helps adhere to the invariant that
|
|
// for all mutation instructions, "oldViewShadowNode" == "current
|
|
// node on mounting layer / stubView".
|
|
// Here we do *not" need to generate a potential DELETE mutation
|
|
// because we know the view is concrete, and still in the new
|
|
// hierarchy.
|
|
mutationContainer.removeMutations.push_back(
|
|
ShadowViewMutation::RemoveMutation(
|
|
parentShadowView,
|
|
otherTreeView,
|
|
static_cast<int>(oldChildPair.mountIndex)));
|
|
continue;
|
|
}
|
|
|
|
mutationContainer.removeMutations.push_back(
|
|
ShadowViewMutation::RemoveMutation(
|
|
parentShadowView,
|
|
oldChildPair.shadowView,
|
|
static_cast<int>(oldChildPair.mountIndex)));
|
|
|
|
deletionCandidatePairs.insert(
|
|
{oldChildPair.shadowView.tag, &oldChildPair});
|
|
|
|
continue;
|
|
}
|
|
}
|
|
|
|
// At this point, oldTag is -1 or is in the new list, and hasn't been
|
|
// inserted or matched yet. We're not sure yet if the new node is in the
|
|
// old list - generate an insert instruction for the new node.
|
|
auto &newChildPair = *newChildPairs[newIndex];
|
|
DEBUG_LOGS({
|
|
LOG(ERROR)
|
|
<< "Differ Branch 10: Inserting tag/tree that was not (yet?) removed from hierarchy: "
|
|
<< newIndex << "/" << newSize << ": ["
|
|
<< newChildPair.shadowView.tag << "]"
|
|
<< (newChildPair.flattened ? " (flattened)" : "")
|
|
<< (newChildPair.isConcreteView ? " (concrete)" : "")
|
|
<< " with parent: [" << parentShadowView.tag << "]";
|
|
});
|
|
if (newChildPair.isConcreteView) {
|
|
mutationContainer.insertMutations.push_back(
|
|
ShadowViewMutation::InsertMutation(
|
|
parentShadowView,
|
|
newChildPair.shadowView,
|
|
static_cast<int>(newChildPair.mountIndex)));
|
|
}
|
|
|
|
// `inOtherTree` is only set to true during flattening/unflattening of
|
|
// parent. If the parent isn't (un)flattened, this will always be
|
|
// `false`, even if the node is in the other (old) tree. In this case,
|
|
// we expect the node to be removed from `newInsertedPairs` when we
|
|
// later encounter it in this loop.
|
|
if (!newChildPair.inOtherTree()) {
|
|
newInsertedPairs.insert({newChildPair.shadowView.tag, &newChildPair});
|
|
}
|
|
|
|
newIndex++;
|
|
}
|
|
|
|
// Penultimate step: generate Delete instructions for entirely deleted
|
|
// subtrees/nodes. We do this here because we need to traverse the entire
|
|
// list to make sure that a node was not reparented into an unflattened
|
|
// node that occurs *after* it in the hierarchy, due to zIndex ordering.
|
|
for (auto &deletionCandidatePair : deletionCandidatePairs) {
|
|
if (deletionCandidatePair.first == 0) {
|
|
continue;
|
|
}
|
|
|
|
auto const &oldChildPair = *deletionCandidatePair.second;
|
|
|
|
DEBUG_LOGS({
|
|
LOG(ERROR)
|
|
<< "Differ Branch 11: Deleting tag/tree that was not in new hierarchy: "
|
|
<< "[" << oldChildPair.shadowView.tag << "]"
|
|
<< (oldChildPair.flattened ? "(flattened)" : "")
|
|
<< (oldChildPair.isConcreteView ? "(concrete)" : "")
|
|
<< (oldChildPair.inOtherTree() ? "(in other tree)" : "")
|
|
<< " with parent: [" << parentShadowView.tag << "] ##"
|
|
<< std::hash<ShadowView>{}(oldChildPair.shadowView);
|
|
});
|
|
|
|
// This can happen when the parent is unflattened
|
|
if (!oldChildPair.inOtherTree() && oldChildPair.isConcreteView) {
|
|
mutationContainer.deleteMutations.push_back(
|
|
ShadowViewMutation::DeleteMutation(oldChildPair.shadowView));
|
|
|
|
// We also have to call the algorithm recursively to clean up the
|
|
// entire subtree starting from the removed view.
|
|
ViewNodePairScope innerScope{};
|
|
calculateShadowViewMutationsV2(
|
|
innerScope,
|
|
mutationContainer.destructiveDownwardMutations,
|
|
oldChildPair.shadowView,
|
|
sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
oldChildPair, innerScope),
|
|
{});
|
|
}
|
|
}
|
|
|
|
// Final step: generate Create instructions for entirely new
|
|
// subtrees/nodes that are not the result of flattening or unflattening.
|
|
for (auto &newInsertedPair : newInsertedPairs) {
|
|
// Erased elements of a TinyMap will have a Tag/key of 0 - skip those
|
|
// These *should* be removed by the map; there are currently no KNOWN
|
|
// cases where TinyMap will do the wrong thing, but there are not yet
|
|
// any unit tests explicitly for TinyMap, so this is safer for now.
|
|
if (newInsertedPair.first == 0) {
|
|
continue;
|
|
}
|
|
|
|
auto const &newChildPair = *newInsertedPair.second;
|
|
|
|
DEBUG_LOGS({
|
|
LOG(ERROR)
|
|
<< "Differ Branch 12: Inserting tag/tree that was not in old hierarchy: "
|
|
<< "[" << newChildPair.shadowView.tag << "]"
|
|
<< (newChildPair.flattened ? "(flattened)" : "")
|
|
<< (newChildPair.isConcreteView ? "(concrete)" : "")
|
|
<< (newChildPair.inOtherTree() ? "(in other tree)" : "")
|
|
<< " with parent: [" << parentShadowView.tag << "]";
|
|
});
|
|
|
|
if (!newChildPair.isConcreteView) {
|
|
continue;
|
|
}
|
|
if (newChildPair.inOtherTree()) {
|
|
continue;
|
|
}
|
|
|
|
mutationContainer.createMutations.push_back(
|
|
ShadowViewMutation::CreateMutation(newChildPair.shadowView));
|
|
|
|
ViewNodePairScope innerScope{};
|
|
calculateShadowViewMutationsV2(
|
|
innerScope,
|
|
mutationContainer.downwardMutations,
|
|
newChildPair.shadowView,
|
|
{},
|
|
sliceChildShadowNodeViewPairsFromViewNodePair(
|
|
newChildPair, innerScope));
|
|
}
|
|
}
|
|
|
|
// All mutations in an optimal order:
|
|
std::move(
|
|
mutationContainer.destructiveDownwardMutations.begin(),
|
|
mutationContainer.destructiveDownwardMutations.end(),
|
|
std::back_inserter(mutations));
|
|
std::move(
|
|
mutationContainer.updateMutations.begin(),
|
|
mutationContainer.updateMutations.end(),
|
|
std::back_inserter(mutations));
|
|
std::move(
|
|
mutationContainer.removeMutations.rbegin(),
|
|
mutationContainer.removeMutations.rend(),
|
|
std::back_inserter(mutations));
|
|
std::move(
|
|
mutationContainer.deleteMutations.begin(),
|
|
mutationContainer.deleteMutations.end(),
|
|
std::back_inserter(mutations));
|
|
std::move(
|
|
mutationContainer.createMutations.begin(),
|
|
mutationContainer.createMutations.end(),
|
|
std::back_inserter(mutations));
|
|
std::move(
|
|
mutationContainer.downwardMutations.begin(),
|
|
mutationContainer.downwardMutations.end(),
|
|
std::back_inserter(mutations));
|
|
std::move(
|
|
mutationContainer.insertMutations.begin(),
|
|
mutationContainer.insertMutations.end(),
|
|
std::back_inserter(mutations));
|
|
}
|
|
|
|
/**
|
|
* Only used by unit tests currently.
|
|
*/
|
|
static void sliceChildShadowNodeViewPairsRecursivelyLegacy(
|
|
ShadowViewNodePair::OwningList &pairList,
|
|
Point layoutOffset,
|
|
ShadowNode const &shadowNode) {
|
|
for (auto const &sharedChildShadowNode : shadowNode.getChildren()) {
|
|
auto &childShadowNode = *sharedChildShadowNode;
|
|
|
|
#ifndef ANDROID
|
|
// Temporary disabled on Android because the mounting infrastructure
|
|
// is not fully ready yet.
|
|
if (childShadowNode.getTraits().check(ShadowNodeTraits::Trait::Hidden)) {
|
|
continue;
|
|
}
|
|
#endif
|
|
|
|
auto shadowView = ShadowView(childShadowNode);
|
|
auto origin = layoutOffset;
|
|
if (shadowView.layoutMetrics != EmptyLayoutMetrics) {
|
|
origin += shadowView.layoutMetrics.frame.origin;
|
|
shadowView.layoutMetrics.frame.origin += layoutOffset;
|
|
}
|
|
|
|
if (childShadowNode.getTraits().check(
|
|
ShadowNodeTraits::Trait::FormsStackingContext)) {
|
|
pairList.push_back({shadowView, &childShadowNode});
|
|
} else {
|
|
if (childShadowNode.getTraits().check(
|
|
ShadowNodeTraits::Trait::FormsView)) {
|
|
pairList.push_back({shadowView, &childShadowNode});
|
|
}
|
|
|
|
sliceChildShadowNodeViewPairsRecursivelyLegacy(
|
|
pairList, origin, childShadowNode);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Only used by unit tests currently.
|
|
*/
|
|
ShadowViewNodePair::OwningList sliceChildShadowNodeViewPairsLegacy(
|
|
ShadowNode const &shadowNode) {
|
|
auto pairList = ShadowViewNodePair::OwningList{};
|
|
|
|
if (!shadowNode.getTraits().check(
|
|
ShadowNodeTraits::Trait::FormsStackingContext) &&
|
|
shadowNode.getTraits().check(ShadowNodeTraits::Trait::FormsView)) {
|
|
return pairList;
|
|
}
|
|
|
|
sliceChildShadowNodeViewPairsRecursivelyLegacy(pairList, {0, 0}, shadowNode);
|
|
|
|
return pairList;
|
|
}
|
|
|
|
ShadowViewMutation::List calculateShadowViewMutations(
|
|
ShadowNode const &oldRootShadowNode,
|
|
ShadowNode const &newRootShadowNode) {
|
|
SystraceSection s("calculateShadowViewMutations");
|
|
|
|
// Root shadow nodes must be belong the same family.
|
|
react_native_assert(
|
|
ShadowNode::sameFamily(oldRootShadowNode, newRootShadowNode));
|
|
|
|
// See explanation of scope in Differentiator.h.
|
|
ViewNodePairScope viewNodePairScope{};
|
|
ViewNodePairScope innerViewNodePairScope{};
|
|
|
|
auto mutations = ShadowViewMutation::List{};
|
|
mutations.reserve(256);
|
|
|
|
auto oldRootShadowView = ShadowView(oldRootShadowNode);
|
|
auto newRootShadowView = ShadowView(newRootShadowNode);
|
|
|
|
if (oldRootShadowView != newRootShadowView) {
|
|
mutations.push_back(ShadowViewMutation::UpdateMutation(
|
|
oldRootShadowView, newRootShadowView, {}));
|
|
}
|
|
|
|
calculateShadowViewMutationsV2(
|
|
innerViewNodePairScope,
|
|
mutations,
|
|
ShadowView(oldRootShadowNode),
|
|
sliceChildShadowNodeViewPairsV2(oldRootShadowNode, viewNodePairScope),
|
|
sliceChildShadowNodeViewPairsV2(newRootShadowNode, viewNodePairScope));
|
|
|
|
return mutations;
|
|
}
|
|
|
|
} // namespace facebook::react
|