fix: freeze deriveds once their containing effects are destroyed#17921
Merged
Conversation
🦋 Changeset detectedLatest commit: 4420e67 The changes in this PR will be included in the next version bump. This PR includes changesets to release 1 package
Not sure what this means? Click here to learn what changesets are. Click here if you're a maintainer who wants to add another changeset to this PR |
Contributor
|
Member
Author
|
/autofix |
1 similar comment
Member
Author
|
/autofix |
dummdidumm
reviewed
Apr 9, 2026
dummdidumm
reviewed
Apr 9, 2026
Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
Rich-Harris
commented
Apr 9, 2026
dummdidumm
reviewed
Apr 9, 2026
dummdidumm
approved these changes
Apr 9, 2026
Merged
6 tasks
Rich-Harris
pushed a commit
that referenced
this pull request
Apr 10, 2026
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@5.55.3 ### Patch Changes - fix: ensure proper HMR updates for dynamic components ([#18079](#18079)) - fix: correctly calculate `@const` blockers ([#18039](#18039)) - fix: freeze deriveds once their containing effects are destroyed ([#17921](#17921)) - fix: defer error boundary rendering in forks ([#18076](#18076)) - fix: avoid false positives for reactivity loss warning ([#18088](#18088)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
1 task
caleb531
added a commit
to caleb531/personal-website
that referenced
this pull request
May 26, 2026
See lengthy comments explaining the issue. This commit fixes a bug caused by <sveltejs/svelte#17921> (released as part of svelte 5.55.3).
caleb531
added a commit
to caleb531/personal-website
that referenced
this pull request
May 27, 2026
See lengthy comments explaining the issue. This commit fixes a bug caused by <sveltejs/svelte#17921> (released as part of svelte 5.55.3).
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Per #17862 (comment), this freezes the value of a derived if it was created inside a parent effect that is now destroyed. This prevents the sort of bug where a derived reads
foo.bareven thoughfoois nowundefined.If the derived is dirty, a warning will be printed.
This PR also gets rid of some weirdness around
derived.parent— it can only ever be anEffect | null, and there's no need forget_derived_parent_effect.Blocked on sveltejs/kit#15533 and a follow-up that switches remote functions to use
$effect.root(since this effectively undoes #17171), hence draft.Before submitting the PR, please make sure you do the following
feat:,fix:,chore:, ordocs:.packages/svelte/src, add a changeset (npx changeset).Tests and linting
pnpm testand lint the project withpnpm lint