* feat: make `<svelte:component>` unnecessary in runes mode
In Svelte 4, writing `<Component />` meant that the component instance is static. If you made the variable `Component` a reactive state variable and updated the component value, the component would not be reinstantiated with the new value - you had to use `<svelte:component>` for that. One reason was that having a dynamic component was more overhead, which is no longer the case in Svelte 5. We can therefore reduce the potential API surface area (by maybe deprecating `<svelte:component>` in the future) by allowing Svelte to recognize when a component variable is potentially dynamic. It turned out that this was already mostly the case. This PR fixes one case where it wasn't, and fixes another where this was wrongfully applied in legacy mode.
* we already have this function
* add interactive demos
* changeset
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
language tools has to type its own shape for backwards compatibility, and it currently doesn't include the `$on` and `$set` methods, which means without widening the type as done here you would get a "this shape is not accepted" type error when passing it to `ComponentProps`
closes#12627
Closes#12643
Very weird behaviour from the draggable setter...if you set element.draggable="false" it will actually set draggable to true (the boolean).
* better code generation for slot props in SSR
* simplify
* remove getters mechanism from server compiler
* changeset
* no need to use getters in SSR mode
* fix comment
* add state.getters as alternative to binding.expression
* on second thoughts
* fix
* first of many
* couple more
* regenerate types
* more
* another
* more
* another
* another
* another
* remove binding.expression from client-side code
* tweak
* last one
* comment
* regenerate types
* add a changeset
* small tidy up
* simplify
* simplify
* simplify and fix
* simplify
* fix: ensure dynamic event handlers are wrapped in a derived
* fix test
* feedback
* more feedback
* address feedback
* we have .svelte.js files
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
* fix: bail-out of hydrating head if no anchor is found
* add failing test
* fix
* fix comment
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
* add invalid_default_snippet error message
* fix: improve validation error that occurs when using `{@render ...}` to render default slotted content
* cheeky hack to keep treeshakeability until we can nuke this validation altogether
Previously, if transitions/animations were playing in quick succession, overlapping each other, it could have disastrous outcomes, leading to elements jumping all over the place.
This PR gets that into much better state (not completely fixed, but close) by applying a few fixes:
- destructure style object from `getComputedStyles`, because it's a live object with getters and we're interested in the fixed values at the beginning
- `unfix` for animations didn't reset the transition styles
- don't apply `fix` when we detect already-running animations on the element. That means it's already away from its original position, and doesn't need fixing. Worse, applying an absolute position can lead to the element jumping to the top left if the running animation also applies a transition style - those take precedence over the one we would apply
fixes#10252
* fix: properly assign trailing comments
Trailing comments were added even if they started before the node end, which violates the definition of trailing comments.
This fixes that, with the consequence that some comments no longer show up in the AST at all. Previously they were stuffed _somewhere_, but arguably at the wrong positions. For example the last comment in a function body got assigned as a trailing comma for the body, which is wrong, because the body ends _after_ the comma.
The special case is comments at the end of an expression tag - they are added even if there are multiple, and they are added regardless of whether they are separated by newlines or not. This ensures the expression tag end is calculated correctly.
Fixes#12466
* support multiple trailing comments after last statement in a body
* simplify, handle object and array expressions
* parse `foo={bar}` attribute as `value: { type: 'ExpressionTag', .. }` (i.e. don't wrap in an array)
* warn on quoted single-expression-attributes
* breaking: warn on quotes single-expression attributes in runes mode
In a future version, that will mean things are getting stringified, which is a departure from how things work today, therefore a warning first.
Related to #7925
* Update .changeset/plenty-items-build.md
* Apply suggestions from code review
* missed a spot
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
The head hydration anchor didn't update after hydrating the contents of one `<svelte:head>` element, which meant subsequent `<svelte:head>` elements would always start at the beginning of the head. This PR fixes that. The test was updated such that the shape of each `<svelte:head>` content is sufficiently different to throw an error if this wasn't fixed.
fixes#12458
* fix: ensure `$state.snapshot` never errors
Snapshotting can error on un-cloneable objects. It's not practical to error in this case; often there's no way out of this for users, so it makes sense to return the original value in that case, and warn in dev mode about it.
closes#12438
* lint
* single warning per snapshot call, list affected properties
* lint
* lint
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
* fix: ensure previous transitions are properly aborted
- nullify options when the transition is aborted. This ensures a change in options is reflected the next time, else it would stick around indefinetly
- abort previous intro (if exists) when new intro plays (same for outro)
fixes#11372
* add a test
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
When Vite calls `hot.accept`, it passes the wrapped component, which means we're passing the HMR wrapper along as the new component. Avoid that by maintaining a reference to the original component.
* feat: add ability to ignore warnings through compiler option
Some people want to disable certain warnings for their whole application without having to add svelte-ignore comments everywhere. This new option makes that possible.
closes#9188
part of https://github.com/sveltejs/language-tools/issues/650
* make it a function
* singular
* warningFilter
* make internal filter non-nullable
* Update .changeset/little-seals-reflect.md
* filter_warning -> warning_filter, for symmetry with public option
* fix
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Co-authored-by: Rich Harris <rich.harris@vercel.com>
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
* 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>
* 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>
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