fix#16404
Currently one file can have multiple exports but only one `cssScopeTo` variable, which is hard coded to `default` inside vite-plugin-svelte.
Therefore set hasGlobal to `true` in case we export a snippet to not have this scoping enabled in v-p-s
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
When an async expression resumes after a pickled `await`, the thunk
returned by `save()` in `reactivity/async.js` calls `restore()` to
re-arm `active_reaction` for the rest of the expression, then disarms it
with `queue_micro_task(unset_context)`. Any microtask already queued
before that one runs inside the restored context. If it writes to a
source, `set()` throws `state_unsafe_mutation` in production, since the
guard is not dev-only. #18453 introduced the queued disarm and noted
this case in review as unavoidable. SvelteKit hits it in practice: its
fetch continuations write to internal `$state` (sveltejs/kit#16914), and
a user's `$derived((await q()).length)` resuming in the same tick makes
that write throw and drops the update signal.
The context restored by a `save` thunk now ends with the synchronous
segment it was restored in. A `restored` flag is set by the thunk and
consumed on entry to `save` and `track_reactivity_loss`, so every
suspension ends it; once an expression contains a pickled await, the
analysis pickles every later await in it too (`has_pickled_await` on
`ExpressionMetadata`), so a trailing await compiles to `$.save` rather
than a bare `await`. At the end of the body, `async_thunk` in
`3-transform/client/utils.js` wraps the return expression in
`$.unsave(...)` when the metadata has a pickled await. If the body
throws instead, the context is unset by `async_derived`'s existing
`finally`, as before. The queued microtask in `save` is removed.
Output is unchanged for expressions that pickle nothing (`$derived(await
a)` compiles byte for byte the same). Expressions with a pickled await
gain one `$.unsave(` call per body, and their trailing await becomes a
`$.save`, 4 to 6 bytes gzipped in the added tests. At runtime a boolean
write replaces a queued microtask per resume. `bench:compare` shows no
difference outside run-to-run noise.
Two runtime tests reproduce the throw without any library involved, one
in dev and one with the prod `await` shape, and fail on `main`.
---------
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Read the Date value through `getTime()` before cloning it to get reactive updates from `SvelteDate`.
Closes#18698
---------
Co-authored-by: svelte-triage-bot <team@svelte.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
include client-created <svelte:head> anchors in the head effect’s DOM range
remove anchors through the existing HEAD_EFFECT teardown
add client and hydration regression coverage for repeated mount/unmount cycles
Fixes#18695
---------
Co-authored-by: svelte-triage-bot <team@svelte.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
closes#15992
This is a minor update to the easing documents. It adds an overview
description for the module and short descriptions for each of the easing
functions.
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Co-authored-by: vercel[bot] <35613825+vercel[bot]@users.noreply.github.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
skip elements inside head, they should not get hashes
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
This PR resolves a `TODO` in `ConstTag.js` regarding the optimization of
simple object pattern matching cases like `{@const { x } = y}`.
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Fixes#15604
Given two nested blocks that both transition:
```svelte
{#if fetching}
<p>loading</p>
{:else}
<div transition:fade>
{#if shown}
<div class="red" transition:fade|global>red square</div>
{/if}
</div>
{/if}
```
and this sequence, where each step happens before the previous fade
finished:
```js
shown = false; // red square starts fading out
fetching = true; // outer block starts fading out too
fetching = false; // 50ms later
```
the red square should finish fading out and be removed, since `shown` is
still false. Instead it fades back in and stays on screen: resuming the
outer block walks the whole subtree, clears `INERT` on every effect and
plays `in()` on every transition it finds — including the inner block's,
so the square's outro is aborted and the removal callback waiting on it
never runs. The inner block has no reason to re-run on its own, `shown`
never changed again.
The root issue is that `INERT` records no ownership — it can't
distinguish "paused by the ancestor currently being resumed" (revive)
from "paused by its own block for its own reasons" (leave alone). The
pause side already has this restraint: `pause_children` refuses to touch
a subtree that is already `INERT`. The resume side had nothing to check.
This PR marks the one effect `pause_effect` was actually called on — the
root of the paused subtree — with a `PAUSED` flag, and gives resume the
same restraint:
```js
function resume_children(effect, local) {
if ((effect.f & PAUSED) !== 0) return;
```
so a resume can only ever undo its own pause; the flag is only cleared
by `resume_effect` on that exact effect. If `shown` flips back to true
while the outer block is paused, this still works: the inner block
effect carries no `PAUSED` itself, so it is resumed and rescheduled,
re-evaluates its condition and revives its own branch.
Fixes#18683.
The printer previously trimmed leading whitespace after an inline
element and failed to replace it when the fragment stayed on one line.
Track that whitespace while grouping fragment nodes and emit a space for
inline output, while retaining newline-based separation for multiline
output.
Adds regression coverage for whitespace following an inline element and
updates existing print snapshots that exposed the same behavior.
Fixes#14205
When a `slide` transition runs on an element without a layout box, for example inside a `display: none` parent, `getComputedStyle` returns values like `auto` for the animated dimensions. These were passed through `parseFloat` unguarded, so the generated css contained `height: NaNpx` and the browser rejected the keyframe property with an "Invalid keyframe value" warning on every transition.
Fix it by omitting properties if they have unparseable numbers - it's the same outcome but you don't see a warning.
---------
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Fix#18465
The style and classe directives are generated using an unique memoizer for all the class/style directive, which means if you have multiple of the same time on one element you have overly broad invalidation/reruns. This fixes it by having one memoizer call per directive instead of collecting them.
---------
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Fixes#18485
Two parts to this:
1. explicitly invoke error boundary during teardown errors, else they go missing/bubble up outside the render tree
2. skip destroying/destroyed boundaries will searching a handler
---------
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Basically, in a situation like this
```svelte
<script lang="ts">
let value = $state('A');
</script>
<input oninput={() => {}} />
<select bind:value>
<button><selectedcontent></selectedcontent></button>
<option>A</option>
<option>B</option>
<option>C</option>
</select>
<style>
select,::picker(select){
appearance: base-select;
}
</style>
```
what happens is that the `oninput` is delegated and so it registers the
global listener (which means it listen on every `oninput` not just the
one from the input). When the select change, the `input` event is
dispatched first, the listener runs, doesn't find an `__input` handler
and returns. Now before the `change` event is emitted, the
`MutationObserver` in `init_select` is triggered by the browser updating
`selectedcontent` and invokes `select_option` with `select.__value`.
However, since the `change` event has yet to fire, `select.__value`
still has the old value, so we "reselect" that. When the change event
runs, the selected option is effectively the old one and the whole thing
breaks.
I had to add the test in `runtime-browser` because JSDom doesn't support
`selectedcontent`
Fixes#18584.
There's multiple parts to this
- abort signal was buggy. It wasn't scoped per render, so cross-talk was possible. Fix by scoping to renderer
- onDestroy callbacks were skipped when something throws. Fix by carefully aborting the rest of the tree, waiting for settle, collect all callbacks and then call them
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Blockers didn't include analyzing implicit store subscriptions, which could also only happen in the template.
Also needs to defer store unsubscribe until after the async template has settled in case the store value is read after an async blocker, in which case unsubscribe synchronously is too soon.
Fixes https://github.com/sveltejs/kit/issues/15119
Fixes#18416.
We previously said that we don't want to handle component instances specifically when they're wrapped with state in #16747 - though the use case presented back then was much more arcane than the one in #18416. Therefore we now don't proxify component instances anymore, which also makes the dev time proxy warning obsolete.
---------
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Each `<svelte:boundary>` with:
```svelte
{#snippet failed(error)}
...
{/snippet}
```
generated a function named failed. Sibling boundaries placed both
functions in the same SSR scope:
```js
{
function failed() {}
function failed() {} // Identifier `failed` has already been declared
}
```
Resulting in a `[PARSE_ERROR] Identifier `failed` has already been
declared` error during build time.
A let declaration such as `{const x = 0}` can create a nested lexical
block, exposing the collision.
The fix gives each boundary its own scope:
```js
{
function failed() {}
$$renderer.boundary({ failed }, ...);
}
{
function failed() {}
$$renderer.boundary({ failed }, ...);
}
``
`render` returns `RenderOutput` and takes `csp: Csp`, but both are
declared in `src/internal/server/types.d.ts` and never exported. The
generated `svelte/server` block has them without `export`, so nothing
outside the repo can import them and the docs page names `RenderOutput`
as the return type with nothing on the page defining it.
Moves them into `src/server/public.d.ts` the way `svelte/motion` went in
#17967, rather than re-exporting internals.
Fixes#18440
`hmr()` in `packages/svelte/src/internal/client/dev/hmr.js` wrapped a
component in a `block` effect containing a `branch` effect. It forwarded
the inner effect's `nodes` object to the outer block:
This shared the same reference, meaning `outer_block.nodes ===
inner_branch.nodes`. When `pause_children` collected transitions for
unmounting, Each collected transition had `out(check)` called multiple times,
starting multiple animations and firing `outroend` multiple times.
Fix by only copying `start`/`end` (the DOM range info the outer block needs)
without sharing the transitions array:
`trace_references` recreated a fresh seen set for every CallExpression,
so `touch` re-walked the same transitive assignment graph once per call.
For N calls reaching an N-deep binding chain, this was $O(N^2)$.
Share one seen set per trace_references invocation. Use separate sets
for the write-directed CallExpression touches and the read-directed
ReturnStatement touches. The shared set ensures each assignment-value
expression is walked at most once, making the traversal linear. `touch`
only ever adds to a fixed target set, so skipping an already-seen
expression never drops a binding: compiler output is byte-identical.
Complements #18548.
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
`to_style()` strips CSS comments from an inline `style` value with
`/\s*\/\*.*?\*\/\s*/g`. The leading `\s*` makes the match retry from
every position, so a long run of whitespace backtracks in O(n^2). When a
dynamic `style={value}` sits on an element that also has a `style:`
directive, that regex runs on `value`, so a large whitespace string can
stall rendering (server) or the main thread (client).
### Fix
Drop the surrounding `\s*` and match only the comment: `/\/\*.*?\*\//g` to prevent quadratic regex.
The surrounding whitespace was already removed by the `.trim()`
---------
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Fixes#18568
`last_propagated_event` was added in #16527 to stop Firefox from garbage collecting the event wrapper mid-propagation. The problem with this is that the even is now retained until the next event, which could be a while. This removes it after a macrotask.
Co-authored-by: rmurphy <rmurphy@fortressinfosec.com>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Fixes#7916. Context lookup starts at the current component, not the
closest parent. `setContext` followed by `getContext` with the same key
in the same component returns the value.
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
The server copy of `createContext` shipped without the `missing_context`
throw and #17580 had to hand-mirror the client body back in, so this
duplication has already cost a bug. This moves the realm-independent
parts, the `createContext` tuple, `get_parent_context`, and
`get_or_init_context_map`, into `internal/shared/context.js`, and each
realm keeps its public context functions as thin wrappers over its own
state.
Fixes#18609
A `<an+b> of <selector>` CSS statement does not need whitespace after `of` if it's followed by a CSS-known syntax (like a `.` which marks a class identifier). Adjust the regex accordingly.
Fixes#18612.
A concise arrow body does not contain a `ReturnStatement` which we traverse in full calculate_blockers (else we bail on functions), so short-cut to `touch` there.
---------
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Fixes#18288
Check the surrounding branch effect's start node to retrieve the correct root node instead of just the anchor, since the latter could come from each.js/branch.js and be a text node that is never going to get connected
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Fixes#18404
`<svelte:head>` combined with two or more components that each use `bind:` on a child component's prop corrupts a renderer's `.type` during SSR, misplacing the head hydration marker in `<body>` instead of `<head>`.
Reason: `copy()` (`packages/svelte/src/internal/server/renderer.js`) rebuilds via `new Renderer(this.global, this.#parent)`. That constructor defaults `.type` from the *parent's* current type, not from `this.type`. To fix it we therefore reassign it (like already do for the boundary elsewhere)
Fixes#18677.
- preserve namespace prefixes on CSS `TypeSelector` AST nodes
- accept wildcard local names in `svg|*` and `*|*`
- retain namespaces when printing modern ASTs
- keep namespaced universal selectors intact while adding scoped CSS
selectors
- add compile and print regressions covering all four namespace forms
---------
Co-authored-by: svelte-triage-bot <team@svelte.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Fixes#18664
`print()` was writing selector names back out verbatim. The parser
decodes CSS escape sequences when it reads them — `\31` becomes `1`,
`\a` becomes a newline — so the printer produced selectors that either
failed to re-parse (`#123`) or silently meant something different
(`#line\nbreak` turns into a descendant combinator).
A small re-escaper (`escape_identifier`) is now used when printing type,
class, id, pseudo, attribute and at-rule names.
Also fixes a backslash parser bug in the process.
---------
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Hi! This PR fixes#18666
### Before submitting the PR, please make sure you do the following
- [x] It's really useful if your PR references an issue where it is
discussed ahead of time. In many cases, features are absent for a
reason. For large changes, please create an RFC:
https://github.com/sveltejs/rfcs
- [x] Prefix your PR title with `feat:`, `fix:`, `chore:`, or `docs:`.
- [x] This message body should clearly illustrate what problems it
solves.
- [x] Ideally, include a test that fails without this PR but passes with
it.
- [x] If this PR changes code within `packages/svelte/src`, add a
changeset (`npx changeset`).
### Tests and linting
- [x] Run the tests with `pnpm test` and lint the project with `pnpm
lint`
Fixes#18592.
Logical assignments to private `$state` fields were compiled as
unconditional setter calls. This preserves JavaScript short-circuiting
by evaluating the setter only when `||=`, `&&=`, or `??=` should assign.
The regression sample covers the no-assignment branch for all three
operators, alongside the existing assignment-path coverage.
### Before submitting the PR, please make sure you do the following
- [x] It's really useful if your PR references an issue where it is
discussed ahead of time. In many cases, features are absent for a
reason. For large changes, please create an RFC:
https://github.com/sveltejs/rfcs
- [x] Prefix your PR title with `feat:`, `fix:`, `chore:`, or `docs:`.
- [x] This message body should clearly illustrate what problems it
solves.
- [x] Ideally, include a test that fails without this PR but passes with
it.
- [x] If this PR changes code within `packages/svelte/src`, add a
changeset (`npx changeset`).
### Tests and linting
- [x] Run the tests with `pnpm test` and lint the project with `pnpm
lint`
Fixes#18304
The parent of a declaration could be the Program, on which HTML comments are added, which subsequently crashes the funciton. Ignore such comments.
---------
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Fixes#18608.
When `set_attributes` normalized removed spread attributes, it also
copied its internal `$$` listener bookkeeping keys into `next` with a
`null` value. This cleared the stored callback before event cleanup, so
removing a capture handler passed `null` to `removeEventListener` and
left the listener attached.
Skip internal `$$` keys during missing-attribute normalization. The
updated runtime-runes sample verifies replacing and then removing a
spread capture handler in both client and hydration modes.
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Fixes#18619
Make sure to not override old values with newer values that are part of the same flush
---------
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Fixes https://github.com/sveltejs/svelte/issues/18607.
For server output, `build_getter` reused a derived binding's declaration
identifier as the generated call callee. Esrap therefore associated
leading declaration comments with an earlier reference, potentially
emitting them immediately after `return` and triggering automatic
semicolon insertion. The getter returned `undefined` instead of the
derived value.
Fix it by avoiding the double-transform.
---------
Co-authored-by: svelte-triage-bot[bot] <316883489+svelte-triage-bot[bot]@users.noreply.github.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
- preserve whitespace around elements if it leads to a line break
- preserve whitespace for whitespace-sensitive elements (pre, textarea,
title)
Co-authored-by: Rich Harris <rich.harris@vercel.com>
Adds a new `comments` array to the stylesheet node which CSS comments
are added to. Is subsequently used in `print` to see them in the output.
Alternative to #18475
Fixes#18610
### Problem
In async mode, a controlled keyed `{#each}` throws `TypeError: Cannot
read properties of undefined (reading 'e')` when its collection becomes
empty while an earlier batch is still pending on the same block.
The fast path in `pause_effects` cleared `state.items` and then called
`destroy_effects`, which walks pending batch keys and reads
`state.items.get(key).e`. Those EachItems are still needed for the
pending batch (preserved offscreen), so clearing the map makes the
dereference throw and aborts the commit mid-flight.
### Fix
Only take the controlled-each fast path when `state.pending.size === 0`,
so pending batches keep their items until they commit or discard.
This PR was opened by the [Changesets
release](https://github.com/changesets/action) GitHub action. When
you're ready to do a release, you can merge this and the packages will
be published to npm automatically. If you're not ready to do a release
yet, that's fine, whenever you add more changesets to main, this PR will
be updated.
# Releases
## svelte@5.56.8
### Patch Changes
- fix: call `onerror` and provide a working `reset` when hydrating a
failed boundary
([#18556](https://github.com/sveltejs/svelte/pull/18556))
- fix: preserve select selection when spread attributes omit value
([#18561](https://github.com/sveltejs/svelte/pull/18561))
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Fixes#18555
A boundary that failed during SSR hydrates via
`#hydrate_failed_content`, which never calls `onerror` and passes the
`failed` snippet a no-op `reset`. Both came in with #17672, whose docs
say `onerror` "will be called upon hydration with the deserialized error
object". Once hydrated as failed, the boundary can never leave that
state. Downstream this is what keeps SvelteKit's `+error.svelte` mounted
after navigating away from a server-rendered error page
(sveltejs/kit#16345).
This extracts the reset/onerror machinery from `#handle_error` into
`#create_reset` and uses it in the hydration path too. `onerror` is
invoked in a microtask because it may mutate state, which is disallowed
while hydrating. `#handle_error` already invokes it asynchronously, so
the timing matches the error path.
The tests flip a `recovered` flag before calling `reset`, since the
child would otherwise throw again. That is the intended retry pattern,
and the same one kit uses when it resets route boundaries on navigation.
Verified against kit end to end, hydrating a server-rendered error page
and navigating away now tears it down with no kit changes needed.
Fixes#18557
A `<select>` with spread attributes initializes the option mutation
observer even when those attributes never provide a `value`. In that
case the element has no internal `__value`, but the observer previously
treated the missing property as an explicit `undefined` value and
deselected every option after an option was added or removed.
Only reapply the programmatic selection when `__value` is actually
present. This preserves the browser's current selection for spreads
without a value while keeping the existing behavior for bindings,
including an explicitly stored `undefined` value.
A runtime-legacy regression fixture covers both adding and removing an
option in client and hydration modes.
### Before submitting
- [x] References the existing issue
- [x] Uses a `fix:` title
- [x] Includes a regression test
- [x] Includes a patch changeset for `svelte`
### Test plan
- [x] `FILTER=select-spread-preserve-selection pnpm test runtime-legacy
--maxWorkers=1` (2 tests passed: client and hydrate)
- [x] `git diff --check`
- [ ] Full `pnpm test` was not run because the shared host was under
resource pressure and broad test processes were explicitly avoided
- [ ] `pnpm lint` and `pnpm check` were not run for the same reason
- [ ] Targeted repository Prettier check was attempted, but could not
start because `prettier-plugin-svelte` required the ungenerated
`packages/svelte/compiler/index.js`; no broad build or dependency
reinstall was run
### AI disclosure
AI-assisted: the implementation, regression test, and pull request text
were prepared with OpenAI Codex and reviewed by the contributor.
Co-authored-by: Paolo Ricciuti <ricciutipaolo@gmail.com>
This PR was opened by the [Changesets
release](https://github.com/changesets/action) GitHub action. When
you're ready to do a release, you can merge this and the packages will
be published to npm automatically. If you're not ready to do a release
yet, that's fine, whenever you add more changesets to main, this PR will
be updated.
# Releases
## svelte@5.56.7
### Patch Changes
- chore: provide `indent` option for `print`
([#18474](https://github.com/sveltejs/svelte/pull/18474))
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Relevant for https://github.com/sveltejs/cli/pull/1138.
This is basically just an option from `esrap` that we pass through. That
will allow tools like `sv migrate` to provide a guessed indent based on
the other file contents and therefore allow us to produce way smaller
diffs. Since we are just passing an option, there is no need for a test
here.
Technically a `feat:` but i dont think this is relevant enough.
### Before submitting the PR, please make sure you do the following
- [x] It's really useful if your PR references an issue where it is
discussed ahead of time. In many cases, features are absent for a
reason. For large changes, please create an RFC:
https://github.com/sveltejs/rfcs
- [x] Prefix your PR title with `feat:`, `fix:`, `chore:`, or `docs:`.
- [x] This message body should clearly illustrate what problems it
solves.
- [ ] Ideally, include a test that fails without this PR but passes with
it.
- [x] If this PR changes code within `packages/svelte/src`, add a
changeset (`npx changeset`).
### Tests and linting
- [x] Run the tests with `pnpm test` and lint the project with `pnpm
lint`
This PR was opened by the [Changesets
release](https://github.com/changesets/action) GitHub action. When
you're ready to do a release, you can merge this and the packages will
be published to npm automatically. If you're not ready to do a release
yet, that's fine, whenever you add more changesets to main, this PR will
be updated.
# Releases
## svelte@5.56.6
### Patch Changes
- perf: skip unnecessary blocker analysis when compiling components
without top-level await
([#18548](https://github.com/sveltejs/svelte/pull/18548))
- fix: rerun derived that had an abort controller on reconnection
([#18551](https://github.com/sveltejs/svelte/pull/18551))
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Skip function reference tracing in `calculate_blockers` when a component
has no top-level `await`.
Blockers only represent dependencies on top-level async statements.
Without a top-level `await`, no binding can have a blocker, so tracing
every top-level function cannot affect the generated output. In large
components with many functions and transitive assignments, that
unnecessary work can become quadratic.
Follow-up to #18400 - we need to mark a derived with an abort signal
that is frozen as dirty so it is guaranteed to rerun when it
reconnects/is re-requested. Else you could return a stale value, or
worse, you returned a promise from the derived which you aborted, and
it's now in the rejected state until you update one of its dependencies.
During my explorations I collected these new tests which are currently
failing. Two of them work on the incremental-batches branch, all of them
(adjusted for new behavior) pass on my uncommitted entangle batches
branch, and all of them also pass on another uncommitted experimental
branch of overlaying deriveds which will likely not land.
Fixes https://github.com/sveltejs/svelte/issues/18301
---------
Co-authored-by: Fedor Nezhivoi <f.nezhivoi@corp.vk.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Fixes#18501.
Problem is that is_updating_effect was also set to true for branch/root effects which are not reactive
---------
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
fixes#18438
Currently the `mark` method inside `#merge` for `earlier_batch` will
schedule effect for undirty derived. Add the condition for derived to
prevent unnecessary effect be scheduled.
```
if ((flags & DERIVED) !== 0) {
mark(/** @type {Derived} */ (reaction));
}
```
## Summary
Fixes#18491 — the compiler discards an upstream plugin's sourcemap when
it's generated without a `source` option (e.g. `new
MagicString(code).generateMap()`), producing wrong devtools/stack-trace
positions.
### Root cause
`compile()` already supports composing an incoming sourcemap into its
output via `options.sourcemap` (`merge_with_preprocessor_map` →
`apply_preprocessor_sourcemap` → `combine_sourcemaps` in
`packages/svelte/src/compiler/utils/mapped_code.js`). This is the same
mechanism `preprocess()` uses internally, and it's the documented
contract for tools that transform a `.svelte` file before compiling it
(see `CompileOptions.sourcemap`'s doc comment).
`combine_sourcemaps` composes maps by matching `sourcefile === filename`
(the basename of the file being compiled). A sourcemap produced by `new
MagicString(code).generateMap()` **without** a `source` option — which
is exactly what the reporter's Vite plugin does — has `sources: ['']`.
That empty string never equals `filename`, so `remapping()` treats the
node as a leaf (the "original" file) instead of a branch to keep
chaining through, and the whole incoming map is silently dropped. The
result: every position that flows through that segment resolves to `{
source: null, line: null, column: null }`, which is what produces the
wrong/missing devtools mapping described in the issue.
Vite itself already has to handle this exact ambiguity: in
`pluginContainer.ts`'s `_getCombinedSourcemap`, an empty `sources[0]`
from a MagicString-based transform is patched to refer to the file being
transformed before Vite uses it internally. This PR applies the same
normalization on svelte's side, so the contract holds regardless of
whether the caller happens to pass a `source` option to `generateMap()`.
### Fix
In `apply_preprocessor_sourcemap`, normalize an incoming map's `sources:
['']` (or `[null]`/`[undefined]`) to `[filename]` before calling
`combine_sourcemaps`, so the chain-matching step can actually find it.
Closes#18506
Declaration tags in the scope of an each block were considered "parts"
and transformed to use their value instead of the signal itself. We can
safely check on the `kind` of the binding since a `kind` of `state`,
`state_raw` or `derived` in the each scope needs to be a declaration tag
(and it's a stable reference so we can use them directly)
This PR was opened by the [Changesets
release](https://github.com/changesets/action) GitHub action. When
you're ready to do a release, you can merge this and the packages will
be published to npm automatically. If you're not ready to do a release
yet, that's fine, whenever you add more changesets to main, this PR will
be updated.
# Releases
## svelte@5.56.4
### Patch Changes
- fix: include wrapping parentheses in `{@const}` declarator `end`
position ([#18436](https://github.com/sveltejs/svelte/pull/18436))
- fix: always unset reactivity context after restoring it
([#18453](https://github.com/sveltejs/svelte/pull/18453))
- fix: don't notify `searchParams` subscribers when the URL changes
without affecting the search string
([#18425](https://github.com/sveltejs/svelte/pull/18425))
- fix: strip `?` from optional parameters in `<script lang="ts">` so
generated JavaScript is valid
([#18448](https://github.com/sveltejs/svelte/pull/18448))
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
When calling `save`, we restore the context after the promise resolves.
But we do not unset it after the subsequent synchronous execution. That
means that until `unset_context` runs in `async_derived` we will not
have the correct (nulled) context. That causes problems if the `save`
isn't the last promise contributing to the `async_derived`, because it
means the context is not properly unset until the promise _after_ the
`save` within the `async_derived` settles. This can cause all sorts of
mixups, including a wrong mutation error.
fixes#18441
`{@const x = (a)}` (and any `{@const}` whose initializer is wrapped in
parentheses, e.g. `(a = b)`, `({ ... })`) produced a
`VariableDeclarator` whose `end` fell before the closing `)`.
`read_expression` strips the wrapping parens from the returned node but
advances the parser past them, so `init.end` excludes the `)` while the
parser position does not. Use the parser position for the declarator
`end` instead. Fixes source slices / tooling that rely on the node range
(the range previously yielded invalid, unbalanced source).
<img width="2064" height="1746" alt="image"
src="https://github.com/user-attachments/assets/64153ee5-d543-442d-8018-d3668acfd7a7"
/>
### Before submitting the PR, please make sure you do the following
- [x] It's really useful if your PR references an issue where it is
discussed ahead of time. In many cases, features are absent for a
reason. For large changes, please create an RFC:
https://github.com/sveltejs/rfcs
- [x] Prefix your PR title with `feat:`, `fix:`, `chore:`, or `docs:`.
- [x] This message body should clearly illustrate what problems it
solves.
- [x] Ideally, include a test that fails without this PR but passes with
it.
- [x] If this PR changes code within `packages/svelte/src`, add a
changeset (`npx changeset`).
### Tests and linting
- [ ] Run the tests with `pnpm test` and lint the project with `pnpm
lint`
`SvelteURLSearchParams` has two notification bugs that surface through
`SvelteURL`.
The first is over-notification. Setting `url.href` always rebuilds the
params and bumps their version signal, even when the search string
didn't change at all. Effects that read `size` (or any params method)
re-run on every unrelated `href` write, which is #17218, where it caused
infinite effect loops in a router. The fix is a guard in the internal
replace path that bails out when the incoming params serialize
identically to the current ones.
The second is under-notification, and it's sneakier. Every read method
tracks the version signal, `get`, `getAll`, `has`, `keys`, `values`,
`entries`, `toString`, `size`, the iterator... except `forEach`, which
was never overridden. The inherited platform method reads the internal
list directly and subscribes to nothing, so a template that renders
params via `forEach` never updates:
```js
$effect(() => {
url.searchParams.forEach((value, key) => entries.push(`${key}=${value}`)); // never re-runs
});
```
We found this one in the wild while making `page.url` a `SvelteURL` in
sveltejs/kit#16031. Kit's own test suite renders query params with
`forEach`, and the coarse object-identity signal that previously masked
the gap went away, leaving stale UI after client-side navigations. The
fix is the same one-line tracking pattern every other read method
already uses.
Fixes#17218
---
- [x] It's really useful if your PR references an issue where it is
discussed ahead of time. In many cases, features are absent for a
reason. For large changes, please create an RFC:
https://github.com/sveltejs/rfcs
- [x] Prefix your PR title with `feat:`, `fix:`, `chore:`, or `docs:`.
- [x] This message body should clearly illustrate what problems it
solves.
- [x] Ideally, include a test that fails without this PR but passes with
it.
- [x] If this PR changes code within `packages/svelte/src`, add a
changeset (`npx changeset`).
### Tests and linting
- [x] Run the tests with `pnpm test` and lint the project with `pnpm
lint`
Bumps [esbuild](https://github.com/evanw/esbuild) from 0.25.11 to
0.28.1.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/evanw/esbuild/releases">esbuild's
releases</a>.</em></p>
<blockquote>
<h2>v0.28.1</h2>
<ul>
<li>
<p>Disallow <code>\</code> in local development server HTTP requests (<a
href="https://github.com/evanw/esbuild/security/advisories/GHSA-g7r4-m6w7-qqqr">GHSA-g7r4-m6w7-qqqr</a>)</p>
<p>This release fixes a security issue where HTTP requests to esbuild's
local development server could traverse outside of the serve directory
on Windows using a <code>\</code> backslash character. It happened due
to the use of Go's <code>path.Clean()</code> function, which only
handles Unix-style <code>/</code> characters. HTTP requests with paths
containing <code>\</code> are no longer allowed.</p>
<p>Thanks to <a
href="https://github.com/dellalibera"><code>@dellalibera</code></a> for
reporting this issue.</p>
</li>
<li>
<p>Add integrity checks to the Deno API (<a
href="https://github.com/evanw/esbuild/security/advisories/GHSA-gv7w-rqvm-qjhr">GHSA-gv7w-rqvm-qjhr</a>)</p>
<p>The previous release of esbuild added integrity checks to esbuild's
npm install script. This release also adds integrity checks to esbuild's
Deno install script. Now esbuild's Deno API will also fail with an error
if the downloaded esbuild binary contains something other than the
expected content.</p>
<p>Note that esbuild's Deno API installs from
<code>registry.npmjs.org</code> by default, but allows the
<code>NPM_CONFIG_REGISTRY</code> environment variable to override this
with a custom package registry. This change means that the esbuild
executable served by <code>NPM_CONFIG_REGISTRY</code> must now match the
expected content.</p>
<p>Thanks to <a
href="https://github.com/sondt99"><code>@sondt99</code></a> for
reporting this issue.</p>
</li>
<li>
<p>Avoid inlining <code>using</code> and <code>await using</code>
declarations (<a
href="https://redirect.github.com/evanw/esbuild/issues/4482">#4482</a>)</p>
<p>Previously esbuild's minifier sometimes incorrectly inlined
<code>using</code> and <code>await using</code> declarations into
subsequent uses of that declaration, which then fails to dispose of the
resource correctly. This bug happened because inlining was done for
<code>let</code> and <code>const</code> declarations by avoiding doing
it for <code>var</code> declarations, which no longer worked when more
declaration types were added. Here's an example:</p>
<pre lang="js"><code>// Original code
{
using x = new Resource()
x.activate()
}
<p>// Old output (with --minify)<br />
new Resource().activate();</p>
<p>// New output (with --minify)<br />
{using e=new Resource;e.activate()}<br />
</code></pre></p>
</li>
<li>
<p>Fix module evaluation when an error is thrown (<a
href="https://redirect.github.com/evanw/esbuild/issues/4461">#4461</a>,
<a
href="https://redirect.github.com/evanw/esbuild/pull/4467">#4467</a>)</p>
<p>If an error is thrown during module evaluation, esbuild previously
didn't preserve the state of the module for subsequent module
references. This was observable if <code>import()</code> or
<code>require()</code> is used to import a module multiple times. The
thrown error is supposed to be thrown by every call to
<code>import()</code> or <code>require()</code>, not just the first.
With this release, esbuild will now throw the same error every time you
call <code>import()</code> or <code>require()</code> on a module that
throws during its evaluation.</p>
</li>
<li>
<p>Fix some edge cases around the <code>new</code> operator (<a
href="https://redirect.github.com/evanw/esbuild/issues/4477">#4477</a>)</p>
<p>Previously esbuild incorrectly printed certain edge cases involving
complex expressions inside the target of a <code>new</code> expression
(specifically an optional chain and/or a tagged template literal). The
generated code for the <code>new</code> target was not correctly wrapped
with parentheses, and either contained a syntax error or had different
semantics. These edge cases have been fixed so that they now correctly
wrap the <code>new</code> target in parentheses. Here is an example of
some affected code:</p>
<pre lang="js"><code>// Original code
new (foo()`bar`)()
new (foo()?.bar)()
<p>// Old output<br />
new foo()<code>bar</code>();<br />
new (foo())?.bar();</p>
<p></code></pre></p>
</li>
</ul>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/evanw/esbuild/blob/main/CHANGELOG-2025.md">esbuild's
changelog</a>.</em></p>
<blockquote>
<h1>Changelog: 2025</h1>
<p>This changelog documents all esbuild versions published in the year
2025 (versions 0.25.0 through 0.27.2).</p>
<h2>0.27.2</h2>
<ul>
<li>
<p>Allow import path specifiers starting with <code>#/</code> (<a
href="https://redirect.github.com/evanw/esbuild/pull/4361">#4361</a>)</p>
<p>Previously the specification for <code>package.json</code> disallowed
import path specifiers starting with <code>#/</code>, but this
restriction <a
href="https://redirect.github.com/nodejs/node/pull/60864">has recently
been relaxed</a> and support for it is being added across the JavaScript
ecosystem. One use case is using it for a wildcard pattern such as
mapping <code>#/*</code> to <code>./src/*</code> (previously you had to
use another character such as <code>#_*</code> instead, which was more
confusing). There is some more context in <a
href="https://redirect.github.com/nodejs/node/issues/49182">nodejs/node#49182</a>.</p>
<p>This change was contributed by <a
href="https://github.com/hybrist"><code>@hybrist</code></a>.</p>
</li>
<li>
<p>Automatically add the <code>-webkit-mask</code> prefix (<a
href="https://redirect.github.com/evanw/esbuild/issues/4357">#4357</a>,
<a
href="https://redirect.github.com/evanw/esbuild/issues/4358">#4358</a>)</p>
<p>This release automatically adds the <code>-webkit-</code> vendor
prefix for the <a
href="https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties/mask"><code>mask</code></a>
CSS shorthand property:</p>
<pre lang="css"><code>/* Original code */
main {
mask: url(x.png) center/5rem no-repeat
}
<p>/* Old output (with --target=chrome110) */<br />
main {<br />
mask: url(x.png) center/5rem no-repeat;<br />
}</p>
<p>/* New output (with --target=chrome110) */<br />
main {<br />
-webkit-mask: url(x.png) center/5rem no-repeat;<br />
mask: url(x.png) center/5rem no-repeat;<br />
}<br />
</code></pre></p>
<p>This change was contributed by <a
href="https://github.com/BPJEnnova"><code>@BPJEnnova</code></a>.</p>
</li>
<li>
<p>Additional minification of <code>switch</code> statements (<a
href="https://redirect.github.com/evanw/esbuild/issues/4176">#4176</a>,
<a
href="https://redirect.github.com/evanw/esbuild/issues/4359">#4359</a>)</p>
<p>This release contains additional minification patterns for reducing
<code>switch</code> statements. Here is an example:</p>
<pre lang="js"><code>// Original code
switch (x) {
case 0:
foo()
break
case 1:
default:
bar()
}
</code></pre>
</li>
</ul>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="bb9db84c02"><code>bb9db84</code></a>
publish 0.28.1 to npm</li>
<li><a
href="9ff053e53b"><code>9ff053e</code></a>
security: add integrity checks to the Deno API</li>
<li><a
href="0a9bf2135b"><code>0a9bf21</code></a>
enforce non-negative size in gzip parser</li>
<li><a
href="e2a1a71320"><code>e2a1a71</code></a>
security: forbid <code>\\</code> in local dev server requests</li>
<li><a
href="83a2cbfc35"><code>83a2cbf</code></a>
fix <a
href="https://redirect.github.com/evanw/esbuild/issues/4482">#4482</a>:
don't inline <code>using</code> declarations</li>
<li><a
href="308ad745d8"><code>308ad74</code></a>
fix <a
href="https://redirect.github.com/evanw/esbuild/issues/4471">#4471</a>:
renaming of nested <code>var</code> declarations</li>
<li><a
href="f013f5f99a"><code>f013f5f</code></a>
fix some typos</li>
<li><a
href="aafd6e48b1"><code>aafd6e4</code></a>
chore: fix some minor issues in comments (<a
href="https://redirect.github.com/evanw/esbuild/issues/4462">#4462</a>)</li>
<li><a
href="15300c30b5"><code>15300c3</code></a>
follow up: cjs evaluation fixes</li>
<li><a
href="1bda0c31d7"><code>1bda0c3</code></a>
fix <a
href="https://redirect.github.com/evanw/esbuild/issues/4461">#4461</a>,
fix <a
href="https://redirect.github.com/evanw/esbuild/issues/4467">#4467</a>:
esm evaluation fixes</li>
<li>Additional commits viewable in <a
href="https://github.com/evanw/esbuild/compare/v0.25.11...v0.28.1">compare
view</a></li>
</ul>
</details>
<details>
<summary>Maintainer changes</summary>
<p>This version was pushed to npm by <a
href="https://www.npmjs.com/~GitHub%20Actions">GitHub Actions</a>, a new
releaser for esbuild since your current version.</p>
</details>
<br />
[](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores)
Dependabot will resolve any conflicts with this PR as long as you don't
alter it yourself. You can also trigger a rebase manually by commenting
`@dependabot rebase`.
[//]: # (dependabot-automerge-start)
[//]: # (dependabot-automerge-end)
---
<details>
<summary>Dependabot commands and options</summary>
<br />
You can trigger Dependabot actions by commenting on this PR:
- `@dependabot rebase` will rebase this PR
- `@dependabot recreate` will recreate this PR, overwriting any edits
that have been made to it
- `@dependabot show <dependency name> ignore conditions` will show all
of the ignore conditions of the specified dependency
- `@dependabot ignore this major version` will close this PR and stop
Dependabot creating any more for this major version (unless you reopen
the PR or upgrade to it yourself)
- `@dependabot ignore this minor version` will close this PR and stop
Dependabot creating any more for this minor version (unless you reopen
the PR or upgrade to it yourself)
- `@dependabot ignore this dependency` will close this PR and stop
Dependabot creating any more for this dependency (unless you reopen the
PR or upgrade to it yourself)
You can disable automated security fix PRs for this repo from the
[Security Alerts
page](https://github.com/sveltejs/svelte/network/alerts).
</details>
Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
This PR was opened by the [Changesets
release](https://github.com/changesets/action) GitHub action. When
you're ready to do a release, you can merge this and the packages will
be published to npm automatically. If you're not ready to do a release
yet, that's fine, whenever you add more changesets to main, this PR will
be updated.
# Releases
## svelte@5.56.3
### Patch Changes
- fix: ignore errors that occur in destroyed effects
([#18384](https://github.com/sveltejs/svelte/pull/18384))
- fix: type BigInts in `$state.snapshot(...)` return values
([#18388](https://github.com/sveltejs/svelte/pull/18388))
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
fixes#18383
I traced the issue to
`packages/svelte/src/internal/client/error-handling.js`, specifically
the `invoke_error_boundary` function. The problem is at line 56 where
`effect.b.error(error)` is called without checking if `effect.b` exists.
What happens is: when an async `$derived` rejects inside a
`<svelte:boundary>`, the error is handled correctly the first time. But
if the boundary is destroyed before the rejection fully settles (e.g.
component unmounts), a subsequent settle tries to call
`effect.b.error()` on a destroyed boundary where `effect.b` is `null`,
causing a `TypeError`.
The fix adds a null check for `effect.b` before calling `error()`. If
the boundary has been destroyed, we skip it and continue bubbling up to
the parent boundary. This way the error still gets handled properly
instead of crashing.
This could also be tested by creating a component with an async
`$derived` that rejects after the component unmounts, but I wanted to
get the fix up first for review.
---------
Co-authored-by: Rich Harris <rich.harris@vercel.com>
Fixes#18385
## Problem
`$state.snapshot` infers BigInt properties as `never` because `bigint`
is missing
from the `Primitive` type definition. BigInt is a valid JavaScript
primitive and is
supported by `structuredClone`.
## Solution
Added `bigint` to the `Primitive` type in both
`packages/svelte/src/ambient.d.ts` and
`packages/svelte/types/index.d.ts`.
## Before
```ts
const object = $state({ number: 1n });
const snapshot = $state.snapshot(object);
// snapshot.number is inferred as never ❌
After
const object = $state({ number: 1n });
const snapshot = $state.snapshot(object);
// snapshot.number is correctly inferred as bigint ✅
Tests and linting
- [x] This is a type-only change, no runtime behavior affected
---------
Co-authored-by: Rich Harris <hello@rich-harris.dev>
By checking that current/previous batch are null we filter out false
positives. `reactivity_loss_tracker` is only reset after a microtask, so
if a flush happens before that, we get warnings for things we shouldn't
warn on.
Fixes#18370
---------
Co-authored-by: Rich Harris <rich.harris@vercel.com>
If a block has a sole component child, we apply an optimization to not
need a template. But if that sole child is wrapped in `$.async`, it can
happens that the block's effect is assigned the wrong end node.
In the reproduction this happens because we have two components inside a
Child which is rendered only after an async block resolves. In
`$.append` we have logic to not reassign nodes when the active effect
didn't already run, which it has by the time we come across it (because
the async work had to resolve first; we added this in
https://github.com/sveltejs/svelte/pull/17120 to prevent the opposite,
nodes being "rewinded" to an earlier position) and so the second sibling
component's `$.append` will not set its end node to the effect. As a
result the end node is wrong (too early).
To fix this we assign the nodes in `$.async`. We could also use
`compareDocumentPosition` in `$.append` to only ever go forward, but
that feels a bit heavier performance-wise.
---------
Co-authored-by: paoloricciuti <ricciutipaolo@gmail.com>
Co-authored-by: Rich Harris <rich.harris@vercel.com>
## Summary
Bumps `vitest` and `@vitest/coverage-v8` from `^2.1.9` to `^4.1.7` (two
major versions). Three small test-harness updates compensate for vitest
4 behavior changes; all 7569 tests still pass.
- **`packages/svelte/tests/runtime-browser/test.ts`** — vitest 4 removed
the deprecated `describe(name, fn, opts)` signature. Pass options as the
second argument.
- **`packages/svelte/tests/runtime-legacy/shared.ts`** — vitest 4's
jsdom env binds `virtualConsole` to the original `globalThis.console`
reference *before* vitest wraps the console, so inline-`<script>` logs
and `jsdomError` events no longer reach per-test `console.{log,error}`
overrides. Restore vitest 2's behavior by re-routing the virtual console
through the live `console` in `beforeAll`. Also promote the window-error
listener to a named function and remove it in `finally` — previously
leaked listeners from earlier tests kept writing to module-level
`unhandled_rejection`, polluting later tests.
- **`vitest.config.js`** — bump `testTimeout` to 10s. The 5s default
trips a handful of dev-mode tests that exercise
`effect_update_depth_exceeded`, whose ~1000 Error-stack captures per
flush are slower under vitest 4's deeper async stacks.
## Test plan
- [x] `pnpm test` — 7569 passed, 63 skipped, 0 failed
---------
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-authored-by: Rich Harris <rich.harris@vercel.com>
The rejects all async deriveds of a batch as `OBSOLETE`, so they don't
hang around and bail early without triggering the batch.
If we don't do this, an async derived can trigger the already done
batch, which schedules an effect that is never flushed. Because it is
never flushed the branches it touched on its way up are never cleared,
and so anything else in that subtree is now unreactive.
Mimic what `parseExpressionAt` does
---------
Co-authored-by: hjaber <hjaber@users.noreply.github.com>
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Detect TypeScript `type` declarations by actually parsing instead of by
character-class blacklists, so that expressions like `{type === 'all' ?
a : b}` or `{type instanceof Foo}` aren't misclassified as malformed
declarations.
Closes#18328
---------
Co-authored-by: Simon Holthausen <simon.holthausen@vercel.com>
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
### Before submitting the PR, please make sure you do the following
- [x] It's really useful if your PR references an issue where it is
discussed ahead of time. In many cases, features are absent for a
reason. For large changes, please create an RFC:
https://github.com/sveltejs/rfcs
- [x] Prefix your PR title with `feat:`, `fix:`, `chore:`, or `docs:`.
- [x] This message body should clearly illustrate what problems it
solves.
- [x] Ideally, include a test that fails without this PR but passes with
it.
- [x] If this PR changes code within `packages/svelte/src`, add a
changeset (`npx changeset`).
### Tests and linting
- [x] Run the tests with `pnpm test` and lint the project with `pnpm
lint`
Fixes#18332.
When spread props put `value` before a later `type="hidden"` on an
`<input>`, `set_attributes` currently writes the value while the element
is still a text input. Browsers sanitize text input values by removing
newlines, so the hidden input permanently loses them before `type` is
applied.
This sets an input's `type` first whenever the same spread update also
includes `value` or `__value`, so the existing value handling runs with
the final input type. The new runtime-browser sample covers both the
problematic spread-first order and the already-working type-first order.
Validation:
- `corepack pnpm lint`
- `CI=1 corepack pnpm test`
- `corepack pnpm vitest run
packages/svelte/tests/runtime-browser/test.ts -t
input-type-before-value-spread`
---------
Co-authored-by: Rich Harris <rich.harris@vercel.com>
Co-authored-by: Rich Harris <hello@rich-harris.dev>
Mathias Picker
JY Wey
Ashok Kaushik
Nic Polumeyv
Bao Nguyen
svelte-triage-bot[bot]
ChaseCopeland
sliang-code
PD Shaheed Ali Khan
adiGuba
Giorgio Maria Federico Birnthaler
Rupankar Dutta
Paolo Ricciuti
Khaled Waleed
Alexander Kireyev
AminBouchareb
Kamil Jakubus
Liam O'Dea
Siddhesh Kabra
github-actions[bot]
Joe Schafer
Mukund Sarma
randalmurphal
kdelay
Magnar Ovedal Myrtveit
Sander Machado
Nathan Asdarjian
Madan kumar
Marwan
Gautier Ben Aïm
subotac
Yuichiro Yamashita
Yuuki Oohara
남정욱
Simon H
Sankalp Thakur
Floze
Manuel
Joe Schafer
prashantg-pixi
Fedor Nezhivoi
Thribhuvan
Rabindra Kumar Meher
Ivan
jyc.dev
dependabot[bot]
sijie-Z
hjaber
Rich Harris
jdoughty04