Related: #7341, #7226
For purely static HTML, instead of walking the node tree and claiming every node/text etc, hydration now uses the same innerHTML optimization technique for hydration compared to normal create. It uses a new data-svelte-h attribute which is added upon server side rendering containing a hash (computed at build time), and then comparing that hash in the client to ensure it's the same node. If the hash is the same, the whole child content is expected to be the same. If the hash is different, the whole child content is replaced with innerHTML.
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Co-authored-by: Ben McCann <322311+benmccann@users.noreply.github.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
* Implement new hydration optimization
During hydration, greedily pick nodes that exist in the original HTML that should not be detached.
Detach the rest.
* Implement optimal reordering during hydration
During hydration we track the order in which children are claimed.
Afterwards, rather than reordering them greedily one-by-one, we reorder all claimed children during the first append optimally.
The optimal reordering first finds the longest subsequence of children that have been claimed in order.
These children will not be moved.
The rest of the children are reordered to where they have to go.
This algorithm is guaranteed to be optimal in the number of reorderings.
The hydration/head-meta-hydrate-duplicate test sample has been modified slightly.
The order in which the <title> tag is being generated changed, which does not affect correctness.
* Fix issue potentially causing extra reorders
Not sorting children before executing the `insertBefore` calls in `init_hydrate` potentially caused extra `insertBefore` calls in `append`
* Simplify`init_hydrate` sorting logic