We've marked several methods used for walking the DOM with a `__NO_SIDE_EFFECTS__` comment. That was good historically, because we didn't need those kept around if its results were unused, but since the hydration changes in #12335 this actually introduces a bug: Because that PR now relies on the hydration nodes being correct due to walking the DOM, tree-shaking unused variables/calls results in the walk being incorrect, leading to bugs
Fixes#12422
* fix: prevent whitespaces merging across component boundaries
The logic that was there didn't take components into account. The underlying problem is that the parent isn't properly set to `Fragment` in all cases because of nested `visit` calls we do in some places.
Fixes#12447
* update test
This enhances our "variable was mutated" detection to also recognize that `foo` in `[foo[1]] = [..]` was mutated. This allows us to be more granular about detecting mutations to each expressions in legacy mode, which fixes#12169
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Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
* move cloning logic into new file, use structuredClone, add tests
* changeset
* breaking
* tweak
* use same cloning approach between server and client
* get types mostly working
* fix type error that popped up
* cheeky hack
* we no longer need deep_snapshot
* shallow copy state when freezing
* throw if argument is a state proxy
* docs
* regenerate
The previous validation for checking if slots with let directives were rendered with `{@render children(...)}` had false positives
- threw an error even if the other side didn't make use of the arguments, i.e. wasn't actually using a let directive
- didn't check that the rendered snippet actually was the children property
This fixes the validation by only applying it to children render tags, and by adding the slot to `$$slots.default` instead of `$$props.children` in more cases (when it's using `<svelte:fragment>` or `let:` directives, which both mean you're using old slot syntax)
Fixes#12414
* fix: cache call expressions in render tag arguments
Ensure that they're called at most once per change, not once per access within the snippet
fixes#12187
* leverage state
* types
* fix
* chore: add support for HMR env flag
* chore: add support for HMR env flag
* chore: add support for HMR env flag
* chore: add support for HMR env flag
* fix: properly delay intro transitions
WAAPI applies the styles of a delayed animation only when that animation starts. In the case of fade-in transitions that means the element is visible, then goes invisible and fades in. Fix that by never applying a delay on intro transitions, instead add keyframes of the initial state for the duration of the delay.
Fixes#10876
* fix bug, make test pass
* make test more selfcontained, test outro delay aswell and add functionality for that in animation-helpers
* lint
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
* fix: more event handling tweaks
- ensure we only have a single document listener per event+runtime
- add `<svelte:body>` listeners to `before_init` similar to the document/window elements
- move some code into `events.js` where it belongs
* add a counter
* changeset
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
* chore: document `@html` and `<img src>` hydration change
Also add a test for it
closes#12333
* add a test
* Update sites/svelte-5-preview/src/routes/docs/content/03-appendix/02-breaking-changes.md
Co-authored-by: Rich Harris <rich.harris@vercel.com>
* lint
* update example and wording
* update test
* since it turns out we already had a test, we can delete the new one
* fix test
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
* feat: runtime dev warn for mismatched `@html`
* fix: limit the length of the client value shown in the error
* put logic inside a helper
* remove $.hash, no longer needed
* fix
* tweak
* update changeset
* fix
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
* separated url-search params and url classes and added more tests
* making URL aware of SvelteURLSearchParams changes so they are in sync
* added changeset
* generated types
* bail out if url.sp and SvelteSp are already in sync
* sync search on searchParams change because of how node18 handles it
* use ts-expect-error instead of ts-ignore
* remove a bit of indirection
* tweak
* fix
* regenerate types
* short-circuit in both directions
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
* chore: reenable server CSS output through a compiler option
There are various use cases where this continues to be necessary/nice to have:
- rendering OG cards
- rendering emails
- basically anything where you use `render` manually and want to quickly stitch together the CSS without setting up an elaborate tooling chain
* cssRenderOnServer -> css: 'injected'
* update tests
* move append_styles into new module, update implementation
* get HMR working
* don't append styles to head when compiling as a custom element
* update changeset
* tweak
* tweak
* tweak wording
* update test
* fix
* reinstate optimisation, but without the bug
* fix sourcemap test
* move breaking change note
* Update packages/svelte/src/internal/server/index.js
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
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Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
* WIP towards single-pass hydration
* fix
* fixes
* fix
* fix
* fixes
* fix
* fixes
* fix
* fix, tidy up
* update script (it currently fails)
* fix
* fix
* hmm
* fix
* fix
* fix
* fix
* all hydration tests passing
* drive-by fix
* fix
* update snapshot tests
* fix
* recover: false
* fix invalid HTML message
* note to self
* fix
* fix
* update snapshot tests
* fix
* fix
* fix
* update test
* fix
* fix
* fix
* ALL TESTS PASSING THIS IS NOT A DRILL
* optimise each blocks
* changeset
* type stuff
* fix comment
* tidy up
* tidy up
* tidy up
* tidy up
* tidy up
* remove comment, turns out we do need it
* revert
* reinstate standalone optimisation
* improve <svelte:element> SSR
* reset more conservatively
* tweak
* DRY/fix
* revert
* simplify
* add comment
* tweak
* simplify
* simplify
* answer: yes, at least for now, because otherwise empty components are a nuisance
* tweak
* unused
* comment is answered by https://github.com/sveltejs/svelte/pull/12356
* tweak
* handle `<template>` edge case at compile time
* this is no longer a possibility, because of is_text_first
* unused
* tweak
* fix
* move annotations to properties
* Update packages/svelte/src/constants.js
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
* Update packages/svelte/src/compiler/phases/3-transform/client/visitors/template.js
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
* Update packages/svelte/src/internal/client/dom/blocks/each.js
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
* Update packages/svelte/src/internal/client/dom/hydration.js
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
* Update playgrounds/demo/vite.config.js
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
* add a comment
* prettier
* tweak
* tighten up hydration tests, add test for standalone component
* test for standalone snippet
* fix
* add some comments
* tidy up
* avoid mutating `arguments`
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Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
assign_nodes inside the branch sets the nodes property, and there's a dependency on the `this` value, which both (on its own) already prevent the effect from being pruned.
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