mirror of
https://github.com/DioxusLabs/dioxus
synced 2024-12-22 02:23:05 +00:00
1524 lines
61 KiB
Rust
1524 lines
61 KiB
Rust
//! This module contains the stateful DiffMachine and all methods to diff VNodes, their properties, and their children.
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//! The DiffMachine calculates the diffs between the old and new frames, updates the new nodes, and modifies the real dom.
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//!
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//! ## Notice:
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//! The inspiration and code for this module was originally taken from Dodrio (@fitzgen) and then modified to support
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//! Components, Fragments, Suspense, SubTree memoization, and additional batching operations.
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//!
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//! ## Implementation Details:
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//!
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//! ### IDs for elements
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//! --------------------
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//! All nodes are addressed by their IDs. The RealDom provides an imperative interface for making changes to these nodes.
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//! We don't necessarily require that DOM changes happen instnatly during the diffing process, so the implementor may choose
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//! to batch nodes if it is more performant for their application. The expectation is that renderers use a Slotmap for nodes
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//! whose keys can be converted to u64 on FFI boundaries.
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//!
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//! When new nodes are created through `render`, they won't know which real node they correspond to. During diffing, we
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//! always make sure to copy over the ID. If we don't do this properly, the ElementId will be populated incorrectly and
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//! brick the user's page.
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//!
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//! ### Fragment Support
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//!
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//! Fragments (nodes without a parent) are supported through a combination of "replace with" and anchor vnodes. Fragments
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//! can be particularly challenging when they are empty, so the placeholder node lets us "reserve" a spot for the empty
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//! fragment to be replaced with when it is no longer empty. This is guaranteed by logic in the NodeFactory - it is
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//! impossible to craft a fragment with 0 elements - they must always have at least a single placeholder element. This is
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//! slightly inefficient, but represents a such an uncommon use case that it is not worth optimizing.
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//!
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//! ## Subtree Memoization
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//! -----------------------
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//! We also employ "subtree memoization" which saves us from having to check trees which take no dynamic content. We can
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//! detect if a subtree is "static" by checking if its children are "static". Since we dive into the tree depth-first, the
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//! calls to "create" propogate this information upwards. Structures like the one below are entirely static:
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//! ```rust
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//! rsx!( div { class: "hello world", "this node is entirely static" } )
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//! ```
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//! Because the subtrees won't be diffed, their "real node" data will be stale (invalid), so its up to the reconciler to
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//! track nodes created in a scope and clean up all relevant data. Support for this is currently WIP
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//!
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//! ## Bloom Filter and Heuristics
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//! ------------------------------
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//! For all components, we employ some basic heuristics to speed up allocations and pre-size bump arenas. The heuristics are
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//! currently very rough, but will get better as time goes on. For FFI, we recommend using a bloom filter to cache strings.
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//!
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//!
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//! ## Garbage Collection
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//! ---------------------
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//! Dioxus uses a passive garbage collection system to clean up old nodes once the work has been completed. This garabge
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//! collection is done internally once the main diffing work is complete. After the "garbage" is collected, Dioxus will then
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//! start to re-use old keys for new nodes. This results in a passive memory management system that is very efficient.
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//!
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//! The IDs used by the key/map are just an index into a vec. This means that Dioxus will drive the key allocation strategy
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//! so the client only needs to maintain a simple list of nodes. By default, Dioxus will not manually clean up old nodes
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//! for the client. As new nodes are created, old nodes will be over-written.
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//!
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//! HEADS-UP:
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//! For now, deferred garabge collection is disabled. The code-paths are almost wired up, but it's quite complex to
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//! get working safely and efficiently. For now, garabge is collected immediately during diffing. This adds extra
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//! overhead, but is faster to implement in the short term.
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//!
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//! Further Reading and Thoughts
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//! ----------------------------
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//! There are more ways of increasing diff performance here that are currently not implemented.
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//! More info on how to improve this diffing algorithm:
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//! - https://hacks.mozilla.org/2019/03/fast-bump-allocated-virtual-doms-with-rust-and-wasm/
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use crate::{arena::SharedResources, innerlude::*};
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use fxhash::{FxHashMap, FxHashSet};
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use smallvec::{smallvec, SmallVec};
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use std::{any::Any, cell::Cell, cmp::Ordering};
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use DomEdit::*;
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/// Instead of having handles directly over nodes, Dioxus uses simple u32 as node IDs.
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/// The expectation is that the underlying renderer will mainain their Nodes in vec where the ids are the index. This allows
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/// for a form of passive garbage collection where nodes aren't immedately cleaned up.
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///
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/// The "RealDom" abstracts over the... real dom. The RealDom trait assumes that the renderer maintains a stack of real
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/// nodes as the diffing algorithm descenes through the tree. This means that whatever is on top of the stack will receive
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/// any modifications that follow. This technique enables the diffing algorithm to avoid directly handling or storing any
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/// target-specific Node type as well as easily serializing the edits to be sent over a network or IPC connection.
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pub trait RealDom<'a> {
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fn raw_node_as_any(&self) -> &mut dyn Any;
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}
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pub struct DiffMachine<'real, 'bump> {
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pub real_dom: &'real dyn RealDom<'bump>,
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pub vdom: &'bump SharedResources,
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pub edits: &'real mut Vec<DomEdit<'bump>>,
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pub scope_stack: SmallVec<[ScopeId; 5]>,
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pub diffed: FxHashSet<ScopeId>,
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// will be used later for garbage collection
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// we check every seen node and then schedule its eventual deletion
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pub seen_scopes: FxHashSet<ScopeId>,
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}
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impl<'real, 'bump> DiffMachine<'real, 'bump> {
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pub(crate) fn new(
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edits: &'real mut Vec<DomEdit<'bump>>,
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dom: &'real dyn RealDom<'bump>,
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cur_scope: ScopeId,
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shared: &'bump SharedResources,
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) -> Self {
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Self {
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real_dom: dom,
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edits,
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scope_stack: smallvec![cur_scope],
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vdom: shared,
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diffed: FxHashSet::default(),
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seen_scopes: FxHashSet::default(),
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}
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}
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/// Allows the creation of a diff machine without the concept of scopes or a virtualdom
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/// this is mostly useful for testing
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///
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/// This will PANIC if any component elements are passed in.
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pub fn new_headless(
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edits: &'real mut Vec<DomEdit<'bump>>,
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dom: &'real dyn RealDom<'bump>,
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shared: &'bump SharedResources,
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) -> Self {
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Self {
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real_dom: dom,
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edits,
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scope_stack: smallvec![ScopeId(0)],
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vdom: shared,
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diffed: FxHashSet::default(),
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seen_scopes: FxHashSet::default(),
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}
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}
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// Diff the `old` node with the `new` node. Emits instructions to modify a
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// physical DOM node that reflects `old` into something that reflects `new`.
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//
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// the real stack should be what it is coming in and out of this function (ideally empty)
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//
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// each function call assumes the stack is fresh (empty).
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pub fn diff_node(&mut self, old_node: &'bump VNode<'bump>, new_node: &'bump VNode<'bump>) {
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match (&old_node.kind, &new_node.kind) {
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// Handle the "sane" cases first.
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// The rsx and html macros strongly discourage dynamic lists not encapsulated by a "Fragment".
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// So the sane (and fast!) cases are where the virtual structure stays the same and is easily diffable.
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(VNodeKind::Text(old), VNodeKind::Text(new)) => {
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let root = old_node.direct_id();
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if old.text != new.text {
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self.edit_push_root(root);
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self.edit_set_text(new.text);
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self.edit_pop();
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}
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new.dom_id.set(Some(root));
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}
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(VNodeKind::Element(old), VNodeKind::Element(new)) => {
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let root = old_node.direct_id();
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// If the element type is completely different, the element needs to be re-rendered completely
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// This is an optimization React makes due to how users structure their code
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//
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// This case is rather rare (typically only in non-keyed lists)
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if new.tag_name != old.tag_name || new.namespace != old.namespace {
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self.replace_node_with_node(root, old_node, new_node);
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return;
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}
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new.dom_id.set(Some(root));
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// Don't push the root if we don't have to
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let mut has_comitted = false;
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let mut please_commit = |edits: &mut Vec<DomEdit>| {
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if !has_comitted {
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has_comitted = true;
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edits.push(PushRoot { id: root.as_u64() });
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}
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};
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// Diff Attributes
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//
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// It's extraordinarily rare to have the number/order of attributes change
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// In these cases, we just completely erase the old set and make a new set
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//
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// TODO: take a more efficient path than this
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if old.attributes.len() == new.attributes.len() {
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for (old_attr, new_attr) in old.attributes.iter().zip(new.attributes.iter()) {
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if old_attr.value != new_attr.value {
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please_commit(&mut self.edits);
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self.edit_set_attribute(new_attr);
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}
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}
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} else {
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// TODO: provide some sort of report on how "good" the diffing was
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please_commit(&mut self.edits);
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for attribute in old.attributes {
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self.edit_remove_attribute(attribute);
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}
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for attribute in new.attributes {
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self.edit_set_attribute(attribute)
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}
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}
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// Diff listeners
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//
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// It's extraordinarily rare to have the number/order of listeners change
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// In the cases where the listeners change, we completely wipe the data attributes and add new ones
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//
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// TODO: take a more efficient path than this
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let cur_scope: ScopeId = self.scope_stack.last().unwrap().clone();
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if old.listeners.len() == new.listeners.len() {
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for (old_l, new_l) in old.listeners.iter().zip(new.listeners.iter()) {
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if old_l.event != new_l.event {
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please_commit(&mut self.edits);
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self.edit_remove_event_listener(old_l.event);
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self.edit_new_event_listener(new_l, cur_scope);
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}
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new_l.mounted_node.set(old_l.mounted_node.get());
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self.fix_listener(new_l);
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}
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} else {
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please_commit(&mut self.edits);
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for listener in old.listeners {
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self.edit_remove_event_listener(listener.event);
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}
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for listener in new.listeners {
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listener.mounted_node.set(Some(root));
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self.edit_new_event_listener(listener, cur_scope);
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// Make sure the listener gets attached to the scope list
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self.fix_listener(listener);
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}
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}
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if has_comitted {
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self.edit_pop();
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}
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// Each child pushes its own root, so it doesn't need our current root
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self.diff_children(old.children, new.children);
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}
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(VNodeKind::Component(old), VNodeKind::Component(new)) => {
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let scope_addr = old.ass_scope.get().unwrap();
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// Make sure we're dealing with the same component (by function pointer)
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if old.user_fc == new.user_fc {
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//
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self.scope_stack.push(scope_addr);
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// Make sure the new component vnode is referencing the right scope id
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new.ass_scope.set(Some(scope_addr));
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// make sure the component's caller function is up to date
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let scope = self.get_scope_mut(&scope_addr).unwrap();
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scope
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.update_scope_dependencies(new.caller.clone(), ScopeChildren(new.children));
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// React doesn't automatically memoize, but we do.
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let compare = old.comparator.unwrap();
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match compare(new) {
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true => {
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// the props are the same...
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}
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false => {
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// the props are different...
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scope.run_scope().unwrap();
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self.diff_node(scope.frames.wip_head(), scope.frames.fin_head());
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}
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}
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self.scope_stack.pop();
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self.seen_scopes.insert(scope_addr);
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} else {
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let mut old_iter = RealChildIterator::new(old_node, &self.vdom);
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let first = old_iter
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.next()
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.expect("Components should generate a placeholder root");
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// remove any leftovers
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for to_remove in old_iter {
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self.edit_push_root(to_remove.direct_id());
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self.edit_remove();
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}
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// seems like we could combine this into a single instruction....
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self.replace_node_with_node(first.direct_id(), old_node, new_node);
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// Wipe the old one and plant the new one
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let old_scope = old.ass_scope.get().unwrap();
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self.destroy_scopes(old_scope);
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}
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}
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(VNodeKind::Fragment(old), VNodeKind::Fragment(new)) => {
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// This is the case where options or direct vnodes might be used.
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// In this case, it's faster to just skip ahead to their diff
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if old.children.len() == 1 && new.children.len() == 1 {
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self.diff_node(&old.children[0], &new.children[0]);
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return;
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}
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self.diff_children(old.children, new.children);
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}
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(VNodeKind::Anchor(old), VNodeKind::Anchor(new)) => {
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new.dom_id.set(old.dom_id.get());
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}
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// The strategy here is to pick the first possible node from the previous set and use that as our replace with root
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//
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// We also walk the "real node" list to make sure all latent roots are claened up
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// This covers the case any time a fragment or component shows up with pretty much anything else
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//
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// This likely isn't the fastest way to go about replacing one node with a virtual node, but the "insane" cases
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// are pretty rare. IE replacing a list (component or fragment) with a single node.
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(
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VNodeKind::Component(_)
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| VNodeKind::Fragment(_)
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| VNodeKind::Text(_)
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| VNodeKind::Element(_)
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| VNodeKind::Anchor(_),
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VNodeKind::Component(_)
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| VNodeKind::Fragment(_)
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| VNodeKind::Text(_)
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| VNodeKind::Element(_)
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| VNodeKind::Anchor(_),
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) => {
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todo!();
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// log::info!(
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// "taking the awkard diffing path {:#?}, {:#?}",
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// old_node,
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// new_node
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// );
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// // currently busted for components - need to fid
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// let root = old_node.dom_id.get().expect(&format!(
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// "Should not be diffing old nodes that were never assigned, {:#?}",
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// old_node
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// ));
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// // Choose the node to use as the placeholder for replacewith
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// let back_node_id = match old_node.kind {
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// // We special case these two types to avoid allocating the small-vecs
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// VNodeKind::Element(_) | VNodeKind::Text(_) => root,
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// _ => {
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// let mut old_iter = RealChildIterator::new(old_node, &self.vdom);
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// let back_node = old_iter
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// .next()
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// .expect("Empty fragments should generate a placeholder.");
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// // remove any leftovers
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// for to_remove in old_iter {
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// self.edit_push_root(to_remove.dom_id().unwrap());
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// self.edit_remove();
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// }
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// back_node.dom_id().unwrap()
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// }
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// };
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// // replace the placeholder or first node with the nodes generated from the "new"
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// self.edit_push_root(back_node_id);
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// let meta = self.create_vnode(new_node);
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// self.edit_replace_with(meta.added_to_stack);
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// // todo use the is_static metadata to update this subtree
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}
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// TODO
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(VNodeKind::Suspended(node), new) => todo!(),
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(old, VNodeKind::Suspended { .. }) => {
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// a node that was once real is now suspended
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//
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}
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}
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}
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// Emit instructions to create the given virtual node.
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//
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// The change list stack may have any shape upon entering this function:
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//
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// [...]
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//
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// When this function returns, the new node is on top of the change list stack:
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//
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// [... node]
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pub fn create_vnode(&mut self, node: &'bump VNode<'bump>) -> CreateMeta {
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log::warn!("Creating node! ... {:#?}", node);
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match &node.kind {
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VNodeKind::Text(text) => {
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let real_id = self.vdom.reserve_node();
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self.edit_create_text_node(text.text, real_id);
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text.dom_id.set(Some(real_id));
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CreateMeta::new(text.is_static, 1)
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}
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VNodeKind::Anchor(anchor) => {
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let real_id = self.vdom.reserve_node();
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self.edit_create_placeholder(real_id);
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anchor.dom_id.set(Some(real_id));
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CreateMeta::new(false, 1)
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}
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VNodeKind::Element(el) => {
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// we have the potential to completely eliminate working on this node in the future(!)
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//
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// This can only be done if all of the elements properties (attrs, children, listeners, etc) are static
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// While creating these things, keep track if we can memoize this element.
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// At the end, we'll set this flag on the element to skip it
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let mut is_static: bool = true;
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let VElement {
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tag_name,
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listeners,
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attributes,
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children,
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namespace,
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static_attrs: _,
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static_children: _,
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static_listeners: _,
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dom_id,
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} = el;
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let real_id = self.vdom.reserve_node();
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if let Some(namespace) = namespace {
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self.edit_create_element(tag_name, Some(namespace), real_id)
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} else {
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self.edit_create_element(tag_name, None, real_id)
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};
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dom_id.set(Some(real_id));
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let cur_scope = self.current_scope().unwrap();
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listeners.iter().for_each(|listener| {
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log::info!("setting listener id to {:#?}", real_id);
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self.fix_listener(listener);
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listener.mounted_node.set(Some(real_id));
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self.edit_new_event_listener(listener, cur_scope.clone());
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// if the node has an event listener, then it must be visited ?
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is_static = false;
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});
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for attr in *attributes {
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is_static = is_static && attr.is_static;
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self.edit_set_attribute(attr);
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}
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// Fast path: if there is a single text child, it is faster to
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// create-and-append the text node all at once via setting the
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// parent's `textContent` in a single change list instruction than
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// to emit three instructions to (1) create a text node, (2) set its
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// text content, and finally (3) append the text node to this
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// parent.
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//
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// Notice: this is a web-specific optimization and may be changed in the future
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//
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// TODO move over
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// if children.len() == 1 {
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// if let VNodeKind::Text(text) = &children[0].kind {
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// self.set_text(text.text);
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// return CreateMeta::new(is_static, 1);
|
|
// }
|
|
// }
|
|
|
|
for child in *children {
|
|
let child_meta = self.create_vnode(child);
|
|
is_static = is_static && child_meta.is_static;
|
|
|
|
// append whatever children were generated by this call
|
|
self.edit_append_children(child_meta.added_to_stack);
|
|
}
|
|
|
|
CreateMeta::new(is_static, 1)
|
|
}
|
|
|
|
VNodeKind::Component(vcomponent) => {
|
|
log::debug!("Mounting a new component");
|
|
let caller = vcomponent.caller.clone();
|
|
|
|
let parent_idx = self.scope_stack.last().unwrap().clone();
|
|
|
|
// Insert a new scope into our component list
|
|
let new_idx = self.vdom.insert_scope_with_key(|new_idx| {
|
|
let parent_scope = self.get_scope(&parent_idx).unwrap();
|
|
let height = parent_scope.height + 1;
|
|
Scope::new(
|
|
caller,
|
|
new_idx,
|
|
Some(parent_idx),
|
|
height,
|
|
ScopeChildren(vcomponent.children),
|
|
self.vdom.clone(),
|
|
)
|
|
});
|
|
|
|
// TODO: abstract this unsafe into the arena abstraction
|
|
let new_component = self.get_scope_mut(&new_idx).unwrap();
|
|
|
|
// Actually initialize the caller's slot with the right address
|
|
vcomponent.ass_scope.set(Some(new_idx));
|
|
|
|
// Run the scope for one iteration to initialize it
|
|
new_component.run_scope().unwrap();
|
|
|
|
// Take the node that was just generated from running the component
|
|
let nextnode = new_component.frames.fin_head();
|
|
|
|
// Push the new scope onto the stack
|
|
self.scope_stack.push(new_idx);
|
|
|
|
// Run the creation algorithm with this scope on the stack
|
|
let meta = self.create_vnode(nextnode);
|
|
|
|
// pop the scope off the stack
|
|
self.scope_stack.pop();
|
|
|
|
if meta.added_to_stack == 0 {
|
|
panic!("This should never happen");
|
|
}
|
|
|
|
// Finally, insert this scope as a seen node.
|
|
self.seen_scopes.insert(new_idx);
|
|
|
|
CreateMeta::new(vcomponent.is_static, meta.added_to_stack)
|
|
}
|
|
|
|
// Fragments are the only nodes that can contain dynamic content (IE through curlies or iterators).
|
|
// We can never ignore their contents, so the prescence of a fragment indicates that we need always diff them.
|
|
// Fragments will just put all their nodes onto the stack after creation
|
|
VNodeKind::Fragment(frag) => self.create_children(frag.children),
|
|
|
|
VNodeKind::Suspended(VSuspended { node: real_node }) => {
|
|
todo!("wip on adding suspense back in");
|
|
// let id = self.vdom.reserve_node();
|
|
// self.edit_create_placeholder(id);
|
|
// node.dom_id.set(Some(id));
|
|
// real_node.set(Some(id));
|
|
// CreateMeta::new(false, 1)
|
|
}
|
|
}
|
|
}
|
|
|
|
fn create_children(&mut self, children: &'bump [VNode<'bump>]) -> CreateMeta {
|
|
let mut is_static = true;
|
|
let mut added_to_stack = 0;
|
|
|
|
for child in children {
|
|
let child_meta = self.create_vnode(child);
|
|
is_static = is_static && child_meta.is_static;
|
|
added_to_stack += child_meta.added_to_stack;
|
|
}
|
|
|
|
CreateMeta {
|
|
is_static,
|
|
added_to_stack,
|
|
}
|
|
}
|
|
|
|
/// Destroy a scope and all of its descendents.
|
|
///
|
|
/// Calling this will run the destuctors on all hooks in the tree.
|
|
/// It will also add the destroyed nodes to the `seen_nodes` cache to prevent them from being renderered.
|
|
fn destroy_scopes(&mut self, old_scope: ScopeId) {
|
|
let mut nodes_to_delete = vec![old_scope];
|
|
let mut scopes_to_explore = vec![old_scope];
|
|
|
|
// explore the scope tree breadth first
|
|
while let Some(scope_id) = scopes_to_explore.pop() {
|
|
// If we're planning on deleting this node, then we don't need to both rendering it
|
|
self.seen_scopes.insert(scope_id);
|
|
let scope = self.get_scope(&scope_id).unwrap();
|
|
for child in scope.descendents.borrow().iter() {
|
|
// Add this node to be explored
|
|
scopes_to_explore.push(child.clone());
|
|
|
|
// Also add it for deletion
|
|
nodes_to_delete.push(child.clone());
|
|
}
|
|
}
|
|
|
|
// Delete all scopes that we found as part of this subtree
|
|
for node in nodes_to_delete {
|
|
log::debug!("Removing scope {:#?}", node);
|
|
let _scope = self.vdom.try_remove(node).unwrap();
|
|
// do anything we need to do to delete the scope
|
|
// I think we need to run the destructors on the hooks
|
|
// TODO
|
|
}
|
|
}
|
|
|
|
// Diff the given set of old and new children.
|
|
//
|
|
// The parent must be on top of the change list stack when this function is
|
|
// entered:
|
|
//
|
|
// [... parent]
|
|
//
|
|
// the change list stack is in the same state when this function returns.
|
|
//
|
|
// If old no anchors are provided, then it's assumed that we can freely append to the parent.
|
|
//
|
|
// Remember, non-empty lists does not mean that there are real elements, just that there are virtual elements.
|
|
fn diff_children(&mut self, old: &'bump [VNode<'bump>], new: &'bump [VNode<'bump>]) {
|
|
const IS_EMPTY: bool = true;
|
|
const IS_NOT_EMPTY: bool = false;
|
|
|
|
match (old.is_empty(), new.is_empty()) {
|
|
(IS_EMPTY, IS_EMPTY) => {}
|
|
|
|
// Completely adding new nodes, removing any placeholder if it exists
|
|
(IS_EMPTY, IS_NOT_EMPTY) => {
|
|
let meta = self.create_children(new);
|
|
self.edit_append_children(meta.added_to_stack);
|
|
}
|
|
|
|
// Completely removing old nodes and putting an anchor in its place
|
|
// no anchor (old has nodes) and the new is empty
|
|
// remove all the old nodes
|
|
(IS_NOT_EMPTY, IS_EMPTY) => {
|
|
for node in old {
|
|
self.remove_vnode(node);
|
|
}
|
|
}
|
|
|
|
(IS_NOT_EMPTY, IS_NOT_EMPTY) => {
|
|
let first_old = &old[0];
|
|
let first_new = &new[0];
|
|
|
|
match (&first_old.kind, &first_new.kind) {
|
|
(VNodeKind::Anchor(old_anchor), VNodeKind::Anchor(new_anchor)) => {
|
|
old_anchor.dom_id.set(new_anchor.dom_id.get());
|
|
}
|
|
(VNodeKind::Anchor(anchor), _) => {
|
|
// replace new anchor with many
|
|
todo!();
|
|
}
|
|
(_, VNodeKind::Anchor(anchor)) => {
|
|
// replace many with new anchor
|
|
todo!();
|
|
}
|
|
_ => {
|
|
let new_is_keyed = new[0].key.is_some();
|
|
let old_is_keyed = old[0].key.is_some();
|
|
|
|
debug_assert!(
|
|
new.iter().all(|n| n.key.is_some() == new_is_keyed),
|
|
"all siblings must be keyed or all siblings must be non-keyed"
|
|
);
|
|
debug_assert!(
|
|
old.iter().all(|o| o.key.is_some() == old_is_keyed),
|
|
"all siblings must be keyed or all siblings must be non-keyed"
|
|
);
|
|
|
|
if new_is_keyed && old_is_keyed {
|
|
self.diff_keyed_children(old, new);
|
|
} else {
|
|
self.diff_non_keyed_children(old, new);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Diffing "keyed" children.
|
|
//
|
|
// With keyed children, we care about whether we delete, move, or create nodes
|
|
// versus mutate existing nodes in place. Presumably there is some sort of CSS
|
|
// transition animation that makes the virtual DOM diffing algorithm
|
|
// observable. By specifying keys for nodes, we know which virtual DOM nodes
|
|
// must reuse (or not reuse) the same physical DOM nodes.
|
|
//
|
|
// This is loosely based on Inferno's keyed patching implementation. However, we
|
|
// have to modify the algorithm since we are compiling the diff down into change
|
|
// list instructions that will be executed later, rather than applying the
|
|
// changes to the DOM directly as we compare virtual DOMs.
|
|
//
|
|
// https://github.com/infernojs/inferno/blob/36fd96/packages/inferno/src/DOM/patching.ts#L530-L739
|
|
//
|
|
// When entering this function, the parent must be on top of the change list
|
|
// stack:
|
|
//
|
|
// [... parent]
|
|
//
|
|
// Upon exiting, the change list stack is in the same state.
|
|
fn diff_keyed_children(&mut self, old: &'bump [VNode<'bump>], new: &'bump [VNode<'bump>]) {
|
|
if cfg!(debug_assertions) {
|
|
let mut keys = fxhash::FxHashSet::default();
|
|
let mut assert_unique_keys = |children: &'bump [VNode<'bump>]| {
|
|
keys.clear();
|
|
for child in children {
|
|
let key = child.key;
|
|
debug_assert!(
|
|
key.is_some(),
|
|
"if any sibling is keyed, all siblings must be keyed"
|
|
);
|
|
keys.insert(key);
|
|
}
|
|
debug_assert_eq!(
|
|
children.len(),
|
|
keys.len(),
|
|
"keyed siblings must each have a unique key"
|
|
);
|
|
};
|
|
assert_unique_keys(old);
|
|
assert_unique_keys(new);
|
|
}
|
|
|
|
// First up, we diff all the nodes with the same key at the beginning of the
|
|
// children.
|
|
//
|
|
// `shared_prefix_count` is the count of how many nodes at the start of
|
|
// `new` and `old` share the same keys.
|
|
let shared_prefix_count = match self.diff_keyed_prefix(old, new) {
|
|
KeyedPrefixResult::Finished => return,
|
|
KeyedPrefixResult::MoreWorkToDo(count) => count,
|
|
};
|
|
|
|
// Next, we find out how many of the nodes at the end of the children have
|
|
// the same key. We do _not_ diff them yet, since we want to emit the change
|
|
// list instructions such that they can be applied in a single pass over the
|
|
// DOM. Instead, we just save this information for later.
|
|
//
|
|
// `shared_suffix_count` is the count of how many nodes at the end of `new`
|
|
// and `old` share the same keys.
|
|
let shared_suffix_count = old[shared_prefix_count..]
|
|
.iter()
|
|
.rev()
|
|
.zip(new[shared_prefix_count..].iter().rev())
|
|
.take_while(|&(old, new)| old.key == new.key)
|
|
.count();
|
|
|
|
let old_shared_suffix_start = old.len() - shared_suffix_count;
|
|
let new_shared_suffix_start = new.len() - shared_suffix_count;
|
|
|
|
// Ok, we now hopefully have a smaller range of children in the middle
|
|
// within which to re-order nodes with the same keys, remove old nodes with
|
|
// now-unused keys, and create new nodes with fresh keys.
|
|
self.diff_keyed_middle(
|
|
&old[shared_prefix_count..old_shared_suffix_start],
|
|
&new[shared_prefix_count..new_shared_suffix_start],
|
|
shared_prefix_count,
|
|
shared_suffix_count,
|
|
old_shared_suffix_start,
|
|
);
|
|
|
|
// Finally, diff the nodes at the end of `old` and `new` that share keys.
|
|
let old_suffix = &old[old_shared_suffix_start..];
|
|
let new_suffix = &new[new_shared_suffix_start..];
|
|
debug_assert_eq!(old_suffix.len(), new_suffix.len());
|
|
if !old_suffix.is_empty() {
|
|
self.diff_keyed_suffix(old_suffix, new_suffix, new_shared_suffix_start)
|
|
}
|
|
}
|
|
|
|
// Diff the prefix of children in `new` and `old` that share the same keys in
|
|
// the same order.
|
|
//
|
|
// Upon entry of this function, the change list stack must be:
|
|
//
|
|
// [... parent]
|
|
//
|
|
// Upon exit, the change list stack is the same.
|
|
fn diff_keyed_prefix(
|
|
&mut self,
|
|
old: &'bump [VNode<'bump>],
|
|
new: &'bump [VNode<'bump>],
|
|
) -> KeyedPrefixResult {
|
|
let mut shared_prefix_count = 0;
|
|
|
|
for (i, (old, new)) in old.iter().zip(new.iter()).enumerate() {
|
|
// abort early if we finally run into nodes with different keys
|
|
if old.key() != new.key() {
|
|
break;
|
|
}
|
|
|
|
self.diff_node(old, new);
|
|
|
|
shared_prefix_count += 1;
|
|
}
|
|
|
|
// If that was all of the old children, then create and append the remaining
|
|
// new children and we're finished.
|
|
if shared_prefix_count == old.len() {
|
|
self.create_and_append_children(&new[shared_prefix_count..]);
|
|
return KeyedPrefixResult::Finished;
|
|
}
|
|
|
|
// And if that was all of the new children, then remove all of the remaining
|
|
// old children and we're finished.
|
|
if shared_prefix_count == new.len() {
|
|
// self.go_to_sibling(shared_prefix_count);
|
|
// self.commit_traversal();
|
|
self.remove_self_and_next_siblings(&old[shared_prefix_count..]);
|
|
return KeyedPrefixResult::Finished;
|
|
}
|
|
|
|
KeyedPrefixResult::MoreWorkToDo(shared_prefix_count)
|
|
}
|
|
|
|
// Create the given children and append them to the parent node.
|
|
//
|
|
// The parent node must currently be on top of the change list stack:
|
|
//
|
|
// [... parent]
|
|
//
|
|
// When this function returns, the change list stack is in the same state.
|
|
pub fn create_and_append_children(&mut self, new: &'bump [VNode<'bump>]) {
|
|
for child in new {
|
|
let meta = self.create_vnode(child);
|
|
self.edit_append_children(meta.added_to_stack);
|
|
}
|
|
}
|
|
|
|
// The most-general, expensive code path for keyed children diffing.
|
|
//
|
|
// We find the longest subsequence within `old` of children that are relatively
|
|
// ordered the same way in `new` (via finding a longest-increasing-subsequence
|
|
// of the old child's index within `new`). The children that are elements of
|
|
// this subsequence will remain in place, minimizing the number of DOM moves we
|
|
// will have to do.
|
|
//
|
|
// Upon entry to this function, the change list stack must be:
|
|
//
|
|
// [... parent]
|
|
//
|
|
// Upon exit from this function, it will be restored to that same state.
|
|
fn diff_keyed_middle(
|
|
&mut self,
|
|
old: &'bump [VNode<'bump>],
|
|
new: &'bump [VNode<'bump>],
|
|
shared_prefix_count: usize,
|
|
shared_suffix_count: usize,
|
|
old_shared_suffix_start: usize,
|
|
) {
|
|
// Should have already diffed the shared-key prefixes and suffixes.
|
|
debug_assert_ne!(new.first().map(|n| n.key()), old.first().map(|o| o.key()));
|
|
debug_assert_ne!(new.last().map(|n| n.key()), old.last().map(|o| o.key()));
|
|
|
|
// The algorithm below relies upon using `u32::MAX` as a sentinel
|
|
// value, so if we have that many new nodes, it won't work. This
|
|
// check is a bit academic (hence only enabled in debug), since
|
|
// wasm32 doesn't have enough address space to hold that many nodes
|
|
// in memory.
|
|
debug_assert!(new.len() < u32::MAX as usize);
|
|
|
|
// Map from each `old` node's key to its index within `old`.
|
|
// IE if the keys were A B C, then we would have (A, 1) (B, 2) (C, 3).
|
|
let mut old_key_to_old_index = old
|
|
.iter()
|
|
.enumerate()
|
|
.map(|(i, o)| (o.key(), i))
|
|
.collect::<FxHashMap<_, _>>();
|
|
|
|
// The set of shared keys between `new` and `old`.
|
|
let mut shared_keys = FxHashSet::default();
|
|
|
|
// Map from each index in `new` to the index of the node in `old` that
|
|
// has the same key.
|
|
let mut new_index_to_old_index = new
|
|
.iter()
|
|
.map(|n| {
|
|
let key = n.key();
|
|
if let Some(&i) = old_key_to_old_index.get(&key) {
|
|
shared_keys.insert(key);
|
|
i
|
|
} else {
|
|
u32::MAX as usize
|
|
}
|
|
})
|
|
.collect::<Vec<_>>();
|
|
|
|
// If none of the old keys are reused by the new children, then we
|
|
// remove all the remaining old children and create the new children
|
|
// afresh.
|
|
if shared_suffix_count == 0 && shared_keys.is_empty() {
|
|
if shared_prefix_count == 0 {
|
|
// self.commit_traversal();
|
|
self.remove_all_children(old);
|
|
} else {
|
|
// self.go_down_to_child(shared_prefix_count);
|
|
// self.commit_traversal();
|
|
self.remove_self_and_next_siblings(&old[shared_prefix_count..]);
|
|
}
|
|
|
|
self.create_and_append_children(new);
|
|
|
|
return;
|
|
}
|
|
|
|
// Save each of the old children whose keys are reused in the new
|
|
// children.
|
|
let mut old_index_to_temp = vec![u32::MAX; old.len()];
|
|
let mut start = 0;
|
|
loop {
|
|
let end = (start..old.len())
|
|
.find(|&i| {
|
|
let key = old[i].key();
|
|
!shared_keys.contains(&key)
|
|
})
|
|
.unwrap_or(old.len());
|
|
|
|
if end - start > 0 {
|
|
// self.commit_traversal();
|
|
// let mut t = self.save_children_to_temporaries(
|
|
// shared_prefix_count + start,
|
|
// shared_prefix_count + end,
|
|
// );
|
|
// for i in start..end {
|
|
// old_index_to_temp[i] = t;
|
|
// t += 1;
|
|
// }
|
|
}
|
|
|
|
debug_assert!(end <= old.len());
|
|
if end == old.len() {
|
|
break;
|
|
} else {
|
|
start = end + 1;
|
|
}
|
|
}
|
|
|
|
// // Remove any old children whose keys were not reused in the new
|
|
// // children. Remove from the end first so that we don't mess up indices.
|
|
// let mut removed_count = 0;
|
|
// for (i, old_child) in old.iter().enumerate().rev() {
|
|
// if !shared_keys.contains(&old_child.key()) {
|
|
// // registry.remove_subtree(old_child);
|
|
// // todo
|
|
// // self.commit_traversal();
|
|
// self.remove(old_child.dom_id.get());
|
|
// self.remove_child(i + shared_prefix_count);
|
|
// removed_count += 1;
|
|
// }
|
|
// }
|
|
|
|
// // If there aren't any more new children, then we are done!
|
|
// if new.is_empty() {
|
|
// return;
|
|
// }
|
|
|
|
// // The longest increasing subsequence within `new_index_to_old_index`. This
|
|
// // is the longest sequence on DOM nodes in `old` that are relatively ordered
|
|
// // correctly within `new`. We will leave these nodes in place in the DOM,
|
|
// // and only move nodes that are not part of the LIS. This results in the
|
|
// // maximum number of DOM nodes left in place, AKA the minimum number of DOM
|
|
// // nodes moved.
|
|
// let mut new_index_is_in_lis = FxHashSet::default();
|
|
// new_index_is_in_lis.reserve(new_index_to_old_index.len());
|
|
// let mut predecessors = vec![0; new_index_to_old_index.len()];
|
|
// let mut starts = vec![0; new_index_to_old_index.len()];
|
|
// longest_increasing_subsequence::lis_with(
|
|
// &new_index_to_old_index,
|
|
// &mut new_index_is_in_lis,
|
|
// |a, b| a < b,
|
|
// &mut predecessors,
|
|
// &mut starts,
|
|
// );
|
|
|
|
// // Now we will iterate from the end of the new children back to the
|
|
// // beginning, diffing old children we are reusing and if they aren't in the
|
|
// // LIS moving them to their new destination, or creating new children. Note
|
|
// // that iterating in reverse order lets us use `Node.prototype.insertBefore`
|
|
// // to move/insert children.
|
|
// //
|
|
// // But first, we ensure that we have a child on the change list stack that
|
|
// // we can `insertBefore`. We handle this once before looping over `new`
|
|
// // children, so that we don't have to keep checking on every loop iteration.
|
|
// if shared_suffix_count > 0 {
|
|
// // There is a shared suffix after these middle children. We will be
|
|
// // inserting before that shared suffix, so add the first child of that
|
|
// // shared suffix to the change list stack.
|
|
// //
|
|
// // [... parent]
|
|
// self.edits
|
|
// .go_down_to_child(old_shared_suffix_start - removed_count);
|
|
// // [... parent first_child_of_shared_suffix]
|
|
// } else {
|
|
// // There is no shared suffix coming after these middle children.
|
|
// // Therefore we have to process the last child in `new` and move it to
|
|
// // the end of the parent's children if it isn't already there.
|
|
// let last_index = new.len() - 1;
|
|
// // uhhhh why an unwrap?
|
|
// let last = new.last().unwrap();
|
|
// // let last = new.last().unwrap_throw();
|
|
// new = &new[..new.len() - 1];
|
|
// if shared_keys.contains(&last.key()) {
|
|
// let old_index = new_index_to_old_index[last_index];
|
|
// let temp = old_index_to_temp[old_index];
|
|
// // [... parent]
|
|
// self.go_down_to_temp_child(temp);
|
|
// // [... parent last]
|
|
// self.diff_node(&old[old_index], last);
|
|
|
|
// if new_index_is_in_lis.contains(&last_index) {
|
|
// // Don't move it, since it is already where it needs to be.
|
|
// } else {
|
|
// // self.commit_traversal();
|
|
// // [... parent last]
|
|
// self.append_child();
|
|
// // [... parent]
|
|
// self.go_down_to_temp_child(temp);
|
|
// // [... parent last]
|
|
// }
|
|
// } else {
|
|
// // self.commit_traversal();
|
|
// // [... parent]
|
|
// self.create(last);
|
|
|
|
// // [... parent last]
|
|
// self.append_child();
|
|
// // [... parent]
|
|
// self.go_down_to_reverse_child(0);
|
|
// // [... parent last]
|
|
// }
|
|
// }
|
|
|
|
// for (new_index, new_child) in new.iter().enumerate().rev() {
|
|
// let old_index = new_index_to_old_index[new_index];
|
|
// if old_index == u32::MAX as usize {
|
|
// debug_assert!(!shared_keys.contains(&new_child.key()));
|
|
// // self.commit_traversal();
|
|
// // [... parent successor]
|
|
// self.create(new_child);
|
|
// // [... parent successor new_child]
|
|
// self.insert_before();
|
|
// // [... parent new_child]
|
|
// } else {
|
|
// debug_assert!(shared_keys.contains(&new_child.key()));
|
|
// let temp = old_index_to_temp[old_index];
|
|
// debug_assert_ne!(temp, u32::MAX);
|
|
|
|
// if new_index_is_in_lis.contains(&new_index) {
|
|
// // [... parent successor]
|
|
// self.go_to_temp_sibling(temp);
|
|
// // [... parent new_child]
|
|
// } else {
|
|
// // self.commit_traversal();
|
|
// // [... parent successor]
|
|
// self.push_temporary(temp);
|
|
// // [... parent successor new_child]
|
|
// self.insert_before();
|
|
// // [... parent new_child]
|
|
// }
|
|
|
|
// self.diff_node(&old[old_index], new_child);
|
|
// }
|
|
// }
|
|
}
|
|
|
|
// Diff the suffix of keyed children that share the same keys in the same order.
|
|
//
|
|
// The parent must be on the change list stack when we enter this function:
|
|
//
|
|
// [... parent]
|
|
//
|
|
// When this function exits, the change list stack remains the same.
|
|
fn diff_keyed_suffix(
|
|
&mut self,
|
|
old: &'bump [VNode<'bump>],
|
|
new: &'bump [VNode<'bump>],
|
|
new_shared_suffix_start: usize,
|
|
) {
|
|
debug_assert_eq!(old.len(), new.len());
|
|
debug_assert!(!old.is_empty());
|
|
|
|
for (i, (old_child, new_child)) in old.iter().zip(new.iter()).enumerate() {
|
|
self.diff_node(old_child, new_child);
|
|
}
|
|
}
|
|
|
|
// Diff children that are not keyed.
|
|
//
|
|
// The parent must be on the top of the change list stack when entering this
|
|
// function:
|
|
//
|
|
// [... parent]
|
|
//
|
|
// the change list stack is in the same state when this function returns.
|
|
fn diff_non_keyed_children(&mut self, old: &'bump [VNode<'bump>], new: &'bump [VNode<'bump>]) {
|
|
// Handled these cases in `diff_children` before calling this function.
|
|
//
|
|
// debug_assert!(!new.is_empty());
|
|
// debug_assert!(!old.is_empty());
|
|
|
|
for (_i, (new_child, old_child)) in new.iter().zip(old.iter()).enumerate() {
|
|
self.diff_node(old_child, new_child);
|
|
}
|
|
|
|
match old.len().cmp(&new.len()) {
|
|
// old.len > new.len -> removing some nodes
|
|
Ordering::Greater => {
|
|
for item in &old[new.len()..] {
|
|
for i in RealChildIterator::new(item, self.vdom) {
|
|
self.edit_push_root(i.direct_id());
|
|
self.edit_remove();
|
|
}
|
|
}
|
|
}
|
|
// old.len < new.len -> adding some nodes
|
|
Ordering::Less => {
|
|
self.create_and_append_children(&new[old.len()..]);
|
|
}
|
|
// old.len == new.len -> no nodes added/removed, but πerhaps changed
|
|
Ordering::Equal => {}
|
|
}
|
|
}
|
|
|
|
// ======================
|
|
// Support methods
|
|
// ======================
|
|
// Remove all of a node's children.
|
|
//
|
|
// The change list stack must have this shape upon entry to this function:
|
|
//
|
|
// [... parent]
|
|
//
|
|
// When this function returns, the change list stack is in the same state.
|
|
fn remove_all_children(&mut self, old: &'bump [VNode<'bump>]) {
|
|
// debug_assert!(self.traversal_is_committed());
|
|
log::debug!("REMOVING CHILDREN");
|
|
for _child in old {
|
|
// registry.remove_subtree(child);
|
|
}
|
|
// Fast way to remove all children: set the node's textContent to an empty
|
|
// string.
|
|
todo!()
|
|
// self.set_inner_text("");
|
|
}
|
|
// Remove the current child and all of its following siblings.
|
|
//
|
|
// The change list stack must have this shape upon entry to this function:
|
|
//
|
|
// [... parent child]
|
|
//
|
|
// After the function returns, the child is no longer on the change list stack:
|
|
//
|
|
// [... parent]
|
|
fn remove_self_and_next_siblings(&self, old: &[VNode<'bump>]) {
|
|
// debug_assert!(self.traversal_is_committed());
|
|
for child in old {
|
|
if let VNodeKind::Component(_vcomp) = child.kind {
|
|
// dom
|
|
// .create_text_node("placeholder for vcomponent");
|
|
|
|
todo!()
|
|
// let root_id = vcomp.stable_addr.as_ref().borrow().unwrap();
|
|
// self.lifecycle_events.push_back(LifeCycleEvent::Remove {
|
|
// root_id,
|
|
// stable_scope_addr: Rc::downgrade(&vcomp.ass_scope),
|
|
// })
|
|
// let id = get_id();
|
|
// *component.stable_addr.as_ref().borrow_mut() = Some(id);
|
|
// self.save_known_root(id);
|
|
// let scope = Rc::downgrade(&component.ass_scope);
|
|
// self.lifecycle_events.push_back(LifeCycleEvent::Mount {
|
|
// caller: Rc::downgrade(&component.caller),
|
|
// root_id: id,
|
|
// stable_scope_addr: scope,
|
|
// });
|
|
}
|
|
|
|
// registry.remove_subtree(child);
|
|
}
|
|
todo!()
|
|
// self.remove_self_and_next_siblings();
|
|
}
|
|
|
|
fn create_garbage(&mut self, node: &'bump VNode<'bump>) {
|
|
let cur_scope = self.current_scope().unwrap();
|
|
let scope = self.get_scope(&cur_scope).unwrap();
|
|
let garbage: &'bump VNode<'static> = unsafe { std::mem::transmute(node) };
|
|
scope.pending_garbage.borrow_mut().push(garbage);
|
|
}
|
|
|
|
fn immediately_dispose_garabage(&mut self, node: ElementId) {
|
|
self.vdom.collect_garbage(node)
|
|
}
|
|
|
|
fn replace_node_with_node(
|
|
&mut self,
|
|
anchor: ElementId,
|
|
old_node: &'bump VNode<'bump>,
|
|
new_node: &'bump VNode<'bump>,
|
|
) {
|
|
self.edit_push_root(anchor);
|
|
let meta = self.create_vnode(new_node);
|
|
self.edit_replace_with(meta.added_to_stack);
|
|
self.create_garbage(old_node);
|
|
self.edit_pop();
|
|
}
|
|
|
|
// assumes
|
|
fn remove_many_and_return_the_first_root(&mut self) -> ElementId {
|
|
todo!()
|
|
}
|
|
|
|
fn remove_vnode(&mut self, node: &'bump VNode<'bump>) {
|
|
match &node.kind {
|
|
VNodeKind::Text(el) => self.immediately_dispose_garabage(node.direct_id()),
|
|
VNodeKind::Element(el) => {
|
|
self.immediately_dispose_garabage(node.direct_id());
|
|
for child in el.children {
|
|
self.remove_vnode(&child);
|
|
}
|
|
}
|
|
VNodeKind::Anchor(a) => {
|
|
//
|
|
}
|
|
VNodeKind::Fragment(frag) => {
|
|
for child in frag.children {
|
|
self.remove_vnode(&child);
|
|
}
|
|
}
|
|
VNodeKind::Component(el) => {
|
|
//
|
|
// self.destroy_scopes(old_scope)
|
|
}
|
|
VNodeKind::Suspended(_) => todo!(),
|
|
}
|
|
}
|
|
|
|
fn current_scope(&self) -> Option<ScopeId> {
|
|
self.scope_stack.last().map(|f| f.clone())
|
|
}
|
|
|
|
fn fix_listener<'a>(&mut self, listener: &'a Listener<'a>) {
|
|
let scope_id = self.current_scope();
|
|
if let Some(scope_id) = scope_id {
|
|
let scope = self.get_scope(&scope_id).unwrap();
|
|
let mut queue = scope.listeners.borrow_mut();
|
|
let long_listener: &'a Listener<'static> = unsafe { std::mem::transmute(listener) };
|
|
queue.push(long_listener as *const _)
|
|
}
|
|
}
|
|
|
|
pub fn get_scope_mut(&mut self, id: &ScopeId) -> Option<&'bump mut Scope> {
|
|
// ensure we haven't seen this scope before
|
|
// if we have, then we're trying to alias it, which is not allowed
|
|
debug_assert!(!self.seen_scopes.contains(id));
|
|
|
|
unsafe { self.vdom.get_scope_mut(*id) }
|
|
}
|
|
pub fn get_scope(&mut self, id: &ScopeId) -> Option<&'bump Scope> {
|
|
// ensure we haven't seen this scope before
|
|
// if we have, then we're trying to alias it, which is not allowed
|
|
unsafe { self.vdom.get_scope(*id) }
|
|
}
|
|
|
|
// Navigation
|
|
pub(crate) fn edit_push_root(&mut self, root: ElementId) {
|
|
let id = root.as_u64();
|
|
self.edits.push(PushRoot { id });
|
|
}
|
|
|
|
pub(crate) fn edit_pop(&mut self) {
|
|
self.edits.push(PopRoot {});
|
|
}
|
|
|
|
// Add Nodes to the dom
|
|
// add m nodes from the stack
|
|
pub(crate) fn edit_append_children(&mut self, many: u32) {
|
|
self.edits.push(AppendChildren { many });
|
|
}
|
|
|
|
// replace the n-m node on the stack with the m nodes
|
|
// ends with the last element of the chain on the top of the stack
|
|
pub(crate) fn edit_replace_with(&mut self, many: u32) {
|
|
self.edits.push(ReplaceWith { many });
|
|
}
|
|
|
|
// Remove Nodesfrom the dom
|
|
pub(crate) fn edit_remove(&mut self) {
|
|
self.edits.push(Remove);
|
|
}
|
|
|
|
// Create
|
|
pub(crate) fn edit_create_text_node(&mut self, text: &'bump str, id: ElementId) {
|
|
let id = id.as_u64();
|
|
self.edits.push(CreateTextNode { text, id });
|
|
}
|
|
|
|
pub(crate) fn edit_create_element(
|
|
&mut self,
|
|
tag: &'static str,
|
|
ns: Option<&'static str>,
|
|
id: ElementId,
|
|
) {
|
|
let id = id.as_u64();
|
|
match ns {
|
|
Some(ns) => self.edits.push(CreateElementNs { id, ns, tag }),
|
|
None => self.edits.push(CreateElement { id, tag }),
|
|
}
|
|
}
|
|
|
|
// placeholders are nodes that don't get rendered but still exist as an "anchor" in the real dom
|
|
pub(crate) fn edit_create_placeholder(&mut self, id: ElementId) {
|
|
let id = id.as_u64();
|
|
self.edits.push(CreatePlaceholder { id });
|
|
}
|
|
|
|
// events
|
|
pub(crate) fn edit_new_event_listener(&mut self, listener: &Listener, scope: ScopeId) {
|
|
let Listener {
|
|
event,
|
|
mounted_node,
|
|
..
|
|
} = listener;
|
|
|
|
let element_id = mounted_node.get().unwrap().as_u64();
|
|
|
|
self.edits.push(NewEventListener {
|
|
scope,
|
|
event_name: event,
|
|
mounted_node_id: element_id,
|
|
});
|
|
}
|
|
|
|
pub(crate) fn edit_remove_event_listener(&mut self, event: &'static str) {
|
|
self.edits.push(RemoveEventListener { event });
|
|
}
|
|
|
|
// modify
|
|
pub(crate) fn edit_set_text(&mut self, text: &'bump str) {
|
|
self.edits.push(SetText { text });
|
|
}
|
|
|
|
pub(crate) fn edit_set_attribute(&mut self, attribute: &'bump Attribute) {
|
|
let Attribute {
|
|
name,
|
|
value,
|
|
is_static,
|
|
is_volatile,
|
|
namespace,
|
|
} = attribute;
|
|
// field: &'static str,
|
|
// value: &'bump str,
|
|
// ns: Option<&'static str>,
|
|
self.edits.push(SetAttribute {
|
|
field: name,
|
|
value,
|
|
ns: *namespace,
|
|
});
|
|
}
|
|
|
|
pub(crate) fn edit_remove_attribute(&mut self, attribute: &Attribute) {
|
|
let name = attribute.name;
|
|
self.edits.push(RemoveAttribute { name });
|
|
}
|
|
}
|
|
|
|
// When we create new nodes, we need to propagate some information back up the call chain.
|
|
// This gives the caller some information on how to handle things like insertins, appending, and subtree discarding.
|
|
pub struct CreateMeta {
|
|
pub is_static: bool,
|
|
pub added_to_stack: u32,
|
|
}
|
|
|
|
impl CreateMeta {
|
|
fn new(is_static: bool, added_to_tack: u32) -> Self {
|
|
Self {
|
|
is_static,
|
|
added_to_stack: added_to_tack,
|
|
}
|
|
}
|
|
}
|
|
|
|
enum KeyedPrefixResult {
|
|
// Fast path: we finished diffing all the children just by looking at the
|
|
// prefix of shared keys!
|
|
Finished,
|
|
// There is more diffing work to do. Here is a count of how many children at
|
|
// the beginning of `new` and `old` we already processed.
|
|
MoreWorkToDo(usize),
|
|
}
|
|
|
|
fn find_first_real_node<'a>(
|
|
nodes: impl IntoIterator<Item = &'a VNode<'a>>,
|
|
scopes: &'a SharedResources,
|
|
) -> Option<&'a VNode<'a>> {
|
|
for node in nodes {
|
|
let mut iter = RealChildIterator::new(node, scopes);
|
|
if let Some(node) = iter.next() {
|
|
return Some(node);
|
|
}
|
|
}
|
|
|
|
None
|
|
}
|
|
|
|
/// This iterator iterates through a list of virtual children and only returns real children (Elements or Text).
|
|
///
|
|
/// This iterator is useful when it's important to load the next real root onto the top of the stack for operations like
|
|
/// "InsertBefore".
|
|
pub struct RealChildIterator<'a> {
|
|
scopes: &'a SharedResources,
|
|
|
|
// Heuristcally we should never bleed into 4 completely nested fragments/components
|
|
// Smallvec lets us stack allocate our little stack machine so the vast majority of cases are sane
|
|
// TODO: use const generics instead of the 4 estimation
|
|
stack: smallvec::SmallVec<[(u16, &'a VNode<'a>); 4]>,
|
|
}
|
|
|
|
impl<'a> RealChildIterator<'a> {
|
|
pub fn new(starter: &'a VNode<'a>, scopes: &'a SharedResources) -> Self {
|
|
Self {
|
|
scopes,
|
|
stack: smallvec::smallvec![(0, starter)],
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'a> Iterator for RealChildIterator<'a> {
|
|
type Item = &'a VNode<'a>;
|
|
|
|
fn next(&mut self) -> Option<&'a VNode<'a>> {
|
|
let mut should_pop = false;
|
|
let mut returned_node: Option<&'a VNode<'a>> = None;
|
|
let mut should_push = None;
|
|
|
|
while returned_node.is_none() {
|
|
if let Some((count, node)) = self.stack.last_mut() {
|
|
match &node.kind {
|
|
// We can only exit our looping when we get "real" nodes
|
|
// This includes fragments and components when they're empty (have a single root)
|
|
VNodeKind::Element(_) | VNodeKind::Text(_) => {
|
|
// We've recursed INTO an element/text
|
|
// We need to recurse *out* of it and move forward to the next
|
|
should_pop = true;
|
|
returned_node = Some(&*node);
|
|
}
|
|
|
|
// If we get a fragment we push the next child
|
|
VNodeKind::Fragment(frag) => {
|
|
let subcount = *count as usize;
|
|
|
|
if frag.children.len() == 0 {
|
|
should_pop = true;
|
|
returned_node = Some(&*node);
|
|
}
|
|
|
|
if subcount >= frag.children.len() {
|
|
should_pop = true;
|
|
} else {
|
|
should_push = Some(&frag.children[subcount]);
|
|
}
|
|
}
|
|
// // If we get a fragment we push the next child
|
|
// VNodeKind::Fragment(frag) => {
|
|
// let subcount = *count as usize;
|
|
|
|
// if frag.children.len() == 0 {
|
|
// should_pop = true;
|
|
// returned_node = Some(&*node);
|
|
// }
|
|
|
|
// if subcount >= frag.children.len() {
|
|
// should_pop = true;
|
|
// } else {
|
|
// should_push = Some(&frag.children[subcount]);
|
|
// }
|
|
// }
|
|
|
|
// Immediately abort suspended nodes - can't do anything with them yet
|
|
VNodeKind::Suspended(node) => {
|
|
// VNodeKind::Suspended => should_pop = true,
|
|
todo!()
|
|
}
|
|
|
|
VNodeKind::Anchor(a) => {
|
|
todo!()
|
|
}
|
|
|
|
// For components, we load their root and push them onto the stack
|
|
VNodeKind::Component(sc) => {
|
|
let scope =
|
|
unsafe { self.scopes.get_scope(sc.ass_scope.get().unwrap()) }.unwrap();
|
|
// let scope = self.scopes.get(sc.ass_scope.get().unwrap()).unwrap();
|
|
|
|
// Simply swap the current node on the stack with the root of the component
|
|
*node = scope.frames.fin_head();
|
|
}
|
|
}
|
|
} else {
|
|
// If there's no more items on the stack, we're done!
|
|
return None;
|
|
}
|
|
|
|
if should_pop {
|
|
self.stack.pop();
|
|
if let Some((id, _)) = self.stack.last_mut() {
|
|
*id += 1;
|
|
}
|
|
should_pop = false;
|
|
}
|
|
|
|
if let Some(push) = should_push {
|
|
self.stack.push((0, push));
|
|
should_push = None;
|
|
}
|
|
}
|
|
|
|
returned_node
|
|
}
|
|
}
|
|
|
|
fn compare_strs(a: &str, b: &str) -> bool {
|
|
// Check by pointer, optimizing for static strs
|
|
if !std::ptr::eq(a, b) {
|
|
// If the pointers are different then check by value
|
|
a == b
|
|
} else {
|
|
true
|
|
}
|
|
}
|