Performance improvements for keyed lists changes

[lifeart]

this is failing tests related to #940

This PR must increase keyed lists swap perf up to 10x! Moon

(See swap rows row)

from this:

to this:

[lifeart]

mutations.map((item)=>{ return item.removedNodes.length ? ['-', item.removedNodes[0]] : ['+', item.addedNodes[0]] }).map(n=>{
	n.push(n[1].textContent);
	return n;
})

from

<li>1</li><li>2</li><li>3</li><li>4</li><li>5</li>

to

<li>1</li><li>4</li><li>3</li><li>2</li><li>5</li>

2 -> 4, 4 -> 2

for @Index test:

for keyed test:

[lifeart]

looks like it's working like this:

for muation [1, 2, 3, 4, 5] to [1, 4, 3, 2, 5]

index-0 - ok.
index-1 - now for el 4, move el 4 to index-1,

• invalidate all index-2 - index-3 nodes (rerender) // to prev element 4 index

add 3 to index-2,
add 2 to index-3

for lists 1-8, 2->7, 7->2

if we found first changed ref, we trying to find last changed ref and invalidate middle?

[lifeart]

Iterator Synchronizer doing a lot of unnecessary work.

for [0...8], 1->7, 7->1

[lifeart]

[0,1,2,3,4,5,6,7,8]

1->7,7->1

[0,7,2,3,4,5,6,1,8]

0 - retain          | [0,1,2,3,4,5,6,7,8]
7 -> move before 1  | [0,7,1,2,3,4,5,6,8]
2 -> move before 8  | [0,7,1,3,4,5,6,2,8]
3 -> move before 8  | [0,7,1,4,5,6,2,3,8]
4 -> move before 8  | [0,7,1,5,6,2,3,4,8]
5 -> move before 8  | [0,7,1,6,2,3,4,5,8]
6 -> move before 8  | [0,7,1,2,3,4,5,6,8]
1 -> move before 8  | [0,7,2,3,4,5,6,1,8]
8 - retain

[lifeart]

how fix work?

cursor 0 -> retain
cursor 1 -> new item, found new item, insert before cursor 1 -> next cursor ...

[lifeart]

@wycats is any updates/fixes I can add?

[wycats]

@lifeart I'm taking a look at this today 😄

Thanks for all the effort!

[wycats]

💥