2479 Commits (svelte@5.53.7)

Author	SHA1	Message	Date
github-actions[bot]	25a1c5368b	Version Packages (#17842) ... 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@5.53.7 ### Patch Changes - fix: correctly add \_\_svelte_meta after else-if chains ([#17830](https://github.com/sveltejs/svelte/pull/17830)) - perf: cache element interactivity and source line splitting in compiler ([#17839](https://github.com/sveltejs/svelte/pull/17839)) - chore: avoid rescheduling effects during branch commit ([#17837](https://github.com/sveltejs/svelte/pull/17837)) - perf: optimize CSS selector pruning ([#17846](https://github.com/sveltejs/svelte/pull/17846)) - fix: preserve original boundary errors when keyed each rows are removed during async updates ([#17843](https://github.com/sveltejs/svelte/pull/17843)) - perf: avoid O(n²) name scanning in scope `generate` and `unique` ([#17844](https://github.com/sveltejs/svelte/pull/17844)) - fix: preserve each items that are needed by pending batches ([#17819](https://github.com/sveltejs/svelte/pull/17819)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Philip Breuer	b7bc1309aa	fix: preserve original boundary errors when keyed each rows are removed during async updates (#17843) ... Fixes a runtime edge case where keyed #each reconciliation can hit a missing item during deferred async updates, causing an internal crash and masking the original boundary error. Fixes #17841 ### 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` --------- Co-authored-by: Rich Harris <rich.harris@vercel.com>	2 months ago
Mathias Picker	0965028d3b	perf: optimize CSS selector pruning (#17846) ... ## Summary Reduces CSS selector pruning overhead by eliminating unnecessary allocations and redundant work in the hot path. **Changes:** - Replace `.slice()` + `.shift()`/`.pop()` in `apply_selector` with index-based `from`/`to` params — avoids O(n) array copies per recursive call - Merge `has_selectors`/`other_selectors` split in `relative_selector_might_apply_to_node` into a single pass — eliminates 2 temporary array allocations per call - Hoist `name.toLowerCase()` out of the inner loop in `attribute_matches` - Replace `value.split(/\s/).includes()` with `indexOf` + boundary checks in `test_attribute` for `~=` — avoids array allocation on every class match - Skip `name.replace()` regex when selector name has no backslash ## Benchmark Interleaved benchmark (5 rounds, alternating baseline/optimized): ``` --- Round 1 --- Baseline: min=59.58ms median=64.63ms Optimized: min=47.20ms median=54.35ms --- Round 2 --- Baseline: min=59.11ms median=64.90ms Optimized: min=48.36ms median=54.74ms --- Round 3 --- Baseline: min=58.38ms median=64.06ms Optimized: min=48.38ms median=53.83ms --- Round 4 --- Baseline: min=58.49ms median=63.99ms Optimized: min=48.45ms median=53.82ms --- Round 5 --- Baseline: min=58.40ms median=64.07ms Optimized: min=48.97ms median=54.64ms Best min: Before=58.38ms After=47.20ms Improvement=19.1% Best median: Before=63.99ms After=53.82ms Improvement=15.9% ``` CPU profile before → after: | Function | Before | After | |---|---|---| | `relative_selector_might_apply_to_node` | 14.3% | 5.2% | | `attribute_matches` | 4.0% | 3.3% | | `test_attribute` | 3.2% | <0.9% | ## Test plan - [x] All 196 CSS tests pass (180 samples + 16 parse) - [x] All 31 snapshot tests pass - [x] All 2380 runtime-runes tests pass - [x] All 3291 runtime-legacy tests pass - [x] All 145 compiler-errors tests pass - [x] All 326 validator tests pass - [x] Added `css-prune-edge-cases` test covering: `~=` word matching (substring vs whole word), deep combinator chains (4+ levels), `:has()` combined with class selectors, escaped selectors, `:is()`/`:where()`/`:not()` with combinators - [x] Edge case test passes on both baseline and optimized code 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com> Co-authored-by: Rich Harris <rich.harris@vercel.com>	2 months ago
Mathias Picker	32111f9e84	perf: avoid O(n²) name scanning in scope generate/unique (#17844) ... ## Summary `Scope.generate()` and `ScopeRoot.unique()` search for available names by iterating from suffix `_1` upward. When the same preferred name is generated many times (e.g. `text` is generated 482 times in a large component), the Nth call re-scans all N-1 already-taken names — O(n²) total work. This adds a `#name_counters` Map to `ScopeRoot` that tracks the next suffix to try per name, so each call resumes from where the last one left off. Generated names are identical to before. ## Benchmark (interleaved, best-of-3 rounds) | Component | Min | Median | |---|---|---| | Realistic (~80 lines) | ~1% | ~7% | | Medium (316 lines) | ~1% | ~5% | | Large (642 lines) | ~7% | ~2% | | XLarge (1302 lines) | **~11%** | **~10%** | ## Test plan - [x] All snapshot tests pass (name generation unchanged) - [x] All validator, compiler-error, runtime-runes, runtime-legacy tests pass 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>	2 months ago
Rich Harris	2f12b60701	chore: avoid reschedule during branch commit (#17837) ... If a dirty effect is resumed — for example `condition` becomes `false` then `count` changes then `condition` becomes `true` again... ```svelte {#if condition} <div transition:fade> {count} </div> {/if} ``` ...then the effect is rescheduled. This happens when branches are committed (after the effect tree is traversed, before effects are flushed). That's undesirable, because it causes another turn of the `flush_effects` loop. It's better if we can handle everything in a single pass, which is what happens in this PR. The trade-off is that we have to traverse the entire effect tree, instead of skipping inert subtrees, which is a trade-off that I think makes sense. The real agenda here is that I'm trying to eliminate all `schedule_effect` calls that happen at inconvenient times, because I have a hunch that if we do that we can return to #17805, which I'm increasingly convinced will be important. (You might have to trust me on this; a full explanation would look a bit charlie-day-meme.jpg. Call it a hunch.) ### 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` --------- Co-authored-by: Vercel <vercel[bot]@users.noreply.github.com>	2 months ago
Rich Harris	86ec210866	fix: correctly add `__svelte_meta` after else-if chains (#17830) ... While looking into something else I spotted the fact that we use `false` to indicate 'else' in an `{#if ...}` block (whether there's an `else` block to render or not). If we instead use `-1`, and use `<!--[0-->` to indicate that the first block in an if-elseif chain was rendered... - instead of `<!--[-->`, we do `<!--[0-->` - instead of `<!--[!-->`, we do `<!--[-1-->` - all others stay the same ...we can simplify things a bit — the `key` argument to `update_branch` is always a number (which probably has some microscopic benefits in terms of making it monomorphic when `else` is defined, and less polymorphic when it isn't), and the hydration mismatch code only needs to consider one type of hydration marker. In the process, I discovered a bug — the dev-time `add_locations` function fails on hydration markers like `<!--[1-->`. This PR fixes it.	2 months ago
Rich Harris	7717ba01b4	fix: preserve each items that are needed by pending batches (#17819) ... This fixes a longstanding TODO with each blocks: currently, if any effects aren't used in the current batch at the moment of reconciliation, they are destroyed. Subsequent batches therefore end up recreating them. This is wasteful at the best of times, but if the effect contains any async work, that work has to be restarted. This PR fixes it by preserving any effects that correspond to the keys of pending batches. It _does_ mean that we need to iterate over each `keys` map for each pending batch in which an each block re-ran, but that is a rare scenario. This feels preferable to the alternative approaches.	2 months ago
Mathias Picker	791d5e332c	perf: cache element interactivity and source line splitting (#17839) ... ## Summary Two small compiler optimizations that reduce redundant work: - **Cache `element_interactivity` per element in a11y checks**: `check_element` was calling `element_interactivity()` up to 10 times per element (via `is_interactive_element`, `is_non_interactive_element`, `is_static_element` wrappers), each time re-iterating schema arrays. Now computed once after building the attribute map and reused. The now-unused wrapper functions are removed. - **Split source lines once in `state.set_source`**: Every compiler warning called `get_code_frame` which split the entire source string with `source.split('\n')`. Now the split happens once in `set_source()` and is exported as `state.source_lines`, naturally cleared by `reset()`. ## Benchmark Synthetic component (80 state vars, 30 each blocks, ~1300 lines): ``` Min Best3 Median Before 66.55ms 67.03ms 73.44ms After 61.14ms 61.90ms 70.63ms Improvement 8.1% 7.7% 3.8% ``` Realistic component (~80 lines, ~25 elements, few warnings): **~1-4%** improvement. The a11y cache scales with element count, the source.split saving scales with warning count. ## Test plan - [x] All 326 validator tests pass (includes all a11y tests) - [x] All 5671 runtime tests pass - [x] 145 compiler-error tests pass 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>	2 months ago
github-actions[bot]	d4c78292ed	Version Packages (#17812) ... 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@5.53.6 ### Patch Changes - perf: optimize parser hot paths for faster compilation ([#17811](https://github.com/sveltejs/svelte/pull/17811)) - fix: `SvelteMap` incorrectly handles keys with `undefined` values ([#17826](https://github.com/sveltejs/svelte/pull/17826)) - fix: SvelteURL `search` setter now returns the normalized value, matching native URL behavior ([#17828](https://github.com/sveltejs/svelte/pull/17828)) - fix: visit synthetic value node during ssr ([#17824](https://github.com/sveltejs/svelte/pull/17824)) - fix: always case insensitive event handlers during ssr ([#17822](https://github.com/sveltejs/svelte/pull/17822)) - chore: more efficient effect scheduling ([#17808](https://github.com/sveltejs/svelte/pull/17808)) - perf: optimize compiler analysis phase ([#17823](https://github.com/sveltejs/svelte/pull/17823)) - fix: skip redundant batch.apply ([#17816](https://github.com/sveltejs/svelte/pull/17816)) - chore: null out current_batch before committing branches ([#17809](https://github.com/sveltejs/svelte/pull/17809)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Mathias Picker	361b32c7cd	fix: SvelteURL search setter uses unnormalized value (#17828) ... ## Summary - The `SvelteURL` `search` setter stored the raw input `value` instead of `super.search`, unlike every other setter in the class - This caused `url.search` to return incorrect values when the URL API normalizes the input (e.g. adding the `?` prefix, or stripping a lone `?`) - For example: `url.search = 'foo=bar'` would return `'foo=bar'` instead of `'?foo=bar'` ## Test plan - [x] Added `url.search normalizes value` test covering: - Setting search without `?` prefix - Setting search with `?` prefix (existing behavior) - Setting search to lone `?` (normalized to `""`) - [x] All existing reactivity tests pass (46/46) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>	2 months ago
Mathias Picker	1043f79d1e	perf: optimize compiler analysis phase (#17823) ... ## Summary Two optimizations to the compiler's analysis phase: - **Cache `ignore_stack` snapshots instead of `structuredClone` on every node.** The universal `_` visitor in the analysis walk runs on every AST node and calls `structuredClone(ignore_stack)` each time. In practice, `svelte-ignore` comments are rare (0–5 per component), so 99%+ of nodes deep-clone an unchanged stack. This adds a copy-on-write cache that only re-creates the snapshot when `push_ignore`/`pop_ignore` actually change the stack. - **Walk the CSS stylesheet once instead of once per element.** `prune()` was called in a loop for each element, each time doing a full `walk()` of the stylesheet AST. This restructures the loop so the stylesheet is walked once, and the element iteration happens inside the `ComplexSelector` visitor. ## Benchmarks Compiled each component 500 times (after 50 warmup iterations), measuring average time per `compile()` call: | Component | Before | After | Speedup | |---|---|---|---| | `has` (80+ CSS selectors, 12 elements) | 3.405 ms | 2.680 ms | **21% faster** | | `siblings-combinator-each-nested` (65 CSS rules, 15 elements) | 2.034 ms | 1.575 ms | **23% faster** | | synthetic (100 CSS rules, 50 elements) | 10.099 ms | 4.564 ms | **55% faster** | The CSS pruning optimization scales with `elements × CSS rules` — the more elements a component has, the bigger the win since we go from N stylesheet walks down to 1. The `structuredClone` fix helps every component regardless of CSS, eliminating ~500–2000 deep clones per compile (one per AST node) and replacing them with 0–5 (one per `svelte-ignore` comment). For typical real-world components with 10–20 elements and some CSS, expect roughly **20–30% faster compilation** in the analysis phase. ## Test plan - [x] Full test suite passes (7329 tests, 0 failures) - [x] CSS pruning tests pass (selector matching, scoping, unused rule detection) - [x] `svelte-ignore` behavior unchanged (snapshot is consumed read-only via `.has()`/`.some()`) 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>	2 months ago
Paolo Ricciuti	b6faa2a905	fix: always case insensitive event handlers during ssr (#17822) ... Fixes events not being stripped on svg, mathml and custom elements. ### 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` --------- Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>	2 months ago
Paolo Ricciuti	e3d277b000	fix: visit synthetic value node during ssr (#17824) ... Closes #17821 ### 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`	2 months ago
Mathias Picker	18db0cab86	fix: SvelteMap incorrectly handles keys with `undefined` values (#17826) ... ## Summary `SvelteMap` had two bugs related to how it checked for key existence internally: ### 1. `has()` and `get()` returned wrong results for keys with `undefined` values Both methods used `super.get(key) !== undefined` to determine if a key existed before creating a per-key reactive source. This fails for keys whose value is legitimately `undefined`, causing: - `has(key)` to return `false` for existing keys with `undefined` values - `get(key)` to skip creating a per-key source and fall back to tracking `version`, resulting in over-notification **Fix:** Replace `super.get(key) !== undefined` with `super.has(key)` in both `has()` and `get()`, matching the pattern already used in `SvelteSet`. ### 2. `delete()` skipped reactive updates when a key had no per-key source The `size` and `version` reactive updates were inside the `if (s !== undefined)` block, meaning they only fired when a per-key source existed (i.e., someone had previously called `has()` or `get()` on that specific key). If a key was added via the constructor or `set()` but never individually read, deleting it would not trigger reactive updates for effects depending on `size` or iterators. **Fix:** Move `set(this.#size, super.size)` and `increment(this.#version)` to a separate `if (res)` block so they fire whenever a key is actually deleted, regardless of whether a per-key source existed. ### Before fix ```js const map = new SvelteMap([['foo', undefined]]); map.has('foo'); // false (should be true) map.get('foo'); // undefined but tracks version instead of per-key source ``` ### After fix ```js const map = new SvelteMap([['foo', undefined]]); map.has('foo'); // true map.get('foo'); // undefined with correct per-key tracking ``` ## Test plan Tests are in `packages/svelte/src/reactivity/map.test.ts`: - `map.has()` returns `true` for constructor-initialized keys with `undefined` values - `map.get()` returns `undefined` with proper per-key reactive tracking - `map.delete()` triggers `has()`/`get()` reactivity for undefined-valued keys - `map.set(key, undefined)` followed by `has()`/`get()` works correctly - `map.delete()` triggers `size` reactivity for keys that were never individually read (no per-key source) - All existing tests pass unchanged 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>	2 months ago
Rich Harris	16a13517ef	fix: skip redundant batch.apply (#17816) ... tiny fix — just realised we're calling `this.apply()` (via `this.activate()`) unnecessarily, since it will happen again immediately after in `flush_effects`	2 months ago
Mathias Picker	efb651cd33	perf: optimize parser hot paths for ~18% faster compilation (#17811) ... ## Summary Optimizes the Svelte compiler's parser phase — the hot path that runs on every file compilation during development (HMR). The changes are surgical micro-optimizations to 7 files in `packages/svelte/src/compiler/phases/1-parse/`, with no architectural changes. ### Changes - **`Parser.match()` — `slice` → `startsWith`**: Avoids creating a new substring on every multi-char match call (called thousands of times per compilation) - **`Parser.match_regex()` — `slice` → sticky flag**: Uses `lastIndex` + `y` flag instead of slicing the entire template string on every regex match. All 14 regex patterns passed to `match_regex`/`read` across 4 files updated with `y` flag. - **`Parser.allow_whitespace()` / `require_whitespace()` — regex → charCode**: Replaces `regex_whitespace.test()` with numeric charCode comparisons in a tight loop (called hundreds of times per compilation). Covers the full `\s` character set with a fast path for common ASCII whitespace. - **Text parser — string concatenation → `slice`**: Replaced `data += template[index++]` loop (O(n²)) with tracking start position + single `slice()` call (O(n)) - **`read_sequence` — string concatenation → `slice`**: Same pattern — derive `raw` from `template.slice()` in `flush()` instead of char-by-char concatenation - **`is_valid_element_name()` — inline regexes → module-level constants**: Extracted 2 regex literals to module scope - **Dynamic `new RegExp()` → `indexOf`**: Replaced `parser.read_until(new RegExp(...))` with `template.indexOf()` for script/style closing tags - **`match_bracket` — `Array.includes` → `Set.has`**: Pre-computes close bracket values as a `Set` for O(1) lookups ## Benchmark A benchmark script was written that: 1. Compiles 5 real test components of varying complexity (a11y validators, form bindings, component migration output, rich selects) 2. Compiles 2 synthetic stress-test templates (500 elements and 2000 elements with expressions and entities) 3. Runs 50 warmup iterations for parse, 20 for compile (JIT warmup) 4. Forces GC between benchmarks via `--expose-gc` 5. Measures both parse-only and full compilation (parse + analyze + transform + codegen) ### Parse-only results | Component | Before | After | Speedup | |---|---|---|---| | a11y-role-supports-aria-props (371 lines) | 2.410ms | 2.129ms | **-11.7%** | | form-default-value-spread (199 lines) | 1.726ms | 1.360ms | **-21.2%** | | svelte-component (251 lines) | 1.925ms | 1.648ms | **-14.4%** | | select-with-rich-content (157 lines) | 0.795ms | 0.636ms | **-20.0%** | | rich-select (173 lines) | 0.807ms | 0.637ms | **-21.1%** | | synthetic-large (500 elements) | 2.560ms | 1.547ms | **-39.6%** | | synthetic-huge (2000 elements) | 136.849ms | 114.115ms | **-16.6%** | | **Total** | **147.071ms** | **122.072ms** | **-17.0%** | ### Full compile results | Component | Before | After | Speedup | |---|---|---|---| | a11y-role-supports-aria-props | 25.407ms | 21.990ms | **-13.4%** | | form-default-value-spread | 10.711ms | 9.422ms | **-12.0%** | | svelte-component | 10.304ms | 8.481ms | **-17.7%** | | select-with-rich-content | 5.986ms | 4.694ms | **-21.6%** | | rich-select | 6.010ms | 5.059ms | **-15.8%** | | synthetic-large (500 elements) | 30.511ms | 25.196ms | **-17.4%** | | synthetic-huge (2000 elements) | 932.801ms | 764.794ms | **-18.0%** | | **Total** | **1021.729ms** | **839.637ms** | **-17.8%** | Benchmarked on macOS, Node.js, Apple Silicon. The parse improvements carry through to end-to-end compile time since the parser is a significant portion of the compilation pipeline. Text-heavy templates benefit the most (up to 40% faster parse). Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>	2 months ago
Rich Harris	5bd4699539	chore: more efficient effect scheduling (#17808) ... This extracts part of #17805 into its own PR that can be merged independently. Today, if a (non-render) effect is created during traversal (e.g. an `{#if condition}` block becomes true, and an `$effect` is created somewhere inside it) then it goes through `schedule_effect`, ultimately causing the loop in `flush_effects` to run again. This is wasteful. We can instead push to an array — `collected_effects` — which is flushed following the first traversal. By using `collected_effects !== null` as a proxy for 'is traversing', we can also simplify the bail-out logic inside `schedule_effect` and make it work in more cases. Bailing out means that in the case that a signal is written to during traversal (which is the case for `each` blocks, for example), we can avoid triggering another turn of the loop because we know that the affected effects are about to be discovered as a result of the ongoing traversal. All this brings us slightly closer to the intermediate goal in #17805 of ensuring that scheduled effects always belong to a specific batch. No test for this because it shouldn't have any user-observable impact, though I've added a changeset out of an abundance of caution.	2 months ago
Rich Harris	b76cd5cafc	chore: null out current_batch before committing branches (#17809) ... Another small tweak extracted from #17805, just to make that diff a bit more legible. By passing the `batch` to the branch commit callback, we don't need to rely on the value of `current_batch` being the same as the batch currently being processed. That gives us more control over the order of operations — for example we can null out `current_batch` _before_ committing branches, which is important (at present, if a state change occurs while those branches are being committed, it will belong to the current batch, but the resulting effects will happen in the context of a _new_ batch, which is something we need to avoid for the sake of #17805). ### 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`	2 months ago
github-actions[bot]	ed14b499d6	Version Packages (#17802) ... 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@5.53.5 ### Patch Changes - fix: escape `innerText` and `textContent` bindings of `contenteditable` ([`0df5abcae223058ceb95491470372065fb87951d`](0df5abcae2)) - fix: sanitize `transformError` values prior to embedding in HTML comments ([`0298e979371bb583855c9810db79a70a551d22b9`](0298e97937)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Paolo Ricciuti	0df5abcae2	Merge commit from fork ... * fix: escape `innerText` and `textContent` bindings of `contenteditable` * fix: better if else structure	2 months ago
Elliott Johnson	0298e97937	Merge commit from fork ... * fix: sanitize `transformError` values prior to embedding in HTML comments * did a little dumb	2 months ago
github-actions[bot]	96fd3ce763	Version Packages (#17786) ... 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@5.53.4 ### Patch Changes - fix: set server context after async transformError ([#17799](https://github.com/sveltejs/svelte/pull/17799)) - fix: hydrate if blocks correctly ([#17784](https://github.com/sveltejs/svelte/pull/17784)) - fix: handle default parameters scope leaks ([#17788](https://github.com/sveltejs/svelte/pull/17788)) - fix: prevent flushed effects from running again ([#17787](https://github.com/sveltejs/svelte/pull/17787)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Simon H	1b3e660519	fix: prevent flushed effects from running again (#17787) ... We never cleared the list of (maybe)dirty_effects on the assumption that once a batch has run them it's complete. But that's not the case when a boundary has a pending snippet, in which case the pending snippet shows up, so `blocking_pending` is already 0 and effects are flushed. That can lead to effects being run unnecessarily, even leading to infinite loops. So we clear them. This is safe because any additional effects would either be scheduled by the boundary (which keeps track of the offscreen effects created while the pending snippet is shown, and schedules them once the pending snippet goes away) or by unskipping skipped branches (which reschedules the effects inside it) Fixes #17717 After creating the test I noticed it fails when run together with other tests, but not alone, which lead me to discover that we're missing an `unset_context`. I also added clearing of `#skipped_branches` just to be safe.	2 months ago
Simon H	673a1ab964	fix: set server context after async transformError (#17799) ... This will get the tests in https://github.com/sveltejs/kit/pull/15308 green, right now they fail because page state cannot be found because context not available	2 months ago
Maurício Kishi	3a289797bd	fix: handle default parameters scope leaks (#17788) ... Use separate scopes for function declarations/expressions and function bodies. This prevents variable declarations from leaking into default parameter initialization expressions. Closes #17785. ### 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`	2 months ago
Simon H	fcdc0289db	fix: hydrate if blocks correctly (#17784) ... We were not using the correct node to analyze the if block marker Fixes #17751	2 months ago
github-actions[bot]	97f3ac5571	Version Packages (#17775) ... 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@5.53.3 ### Patch Changes - fix: render `:catch` of `#await` block with correct key ([#17769](https://github.com/sveltejs/svelte/pull/17769)) - chore: pin aria-query@5.3.1 ([#17772](https://github.com/sveltejs/svelte/pull/17772)) - fix: make string coercion consistent to `toString` ([#17774](https://github.com/sveltejs/svelte/pull/17774)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Simon H	7deedc5bb4	fix: render `:catch` of `#await` block with correct key (#17769) ... Fixes #17678	2 months ago
Paolo Ricciuti	f67d03df5b	fix: make string coercion consistent to `toString` (#17774) ... Closes #17758 ### 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`	2 months ago
Conduitry	4e29eee4b0	chore: pin aria-query@5.3.1 (#17772) ... The only change between 5.3.1 and 5.3.2 is 2106d5e872 to support versions of Node before 4, with the cost of a minuscule but pointless performance hit. This is a pretty stable library, and there have been no further changes in the ensuing year and a half, so it seems pretty safe to pin to the previous version. ### Before submitting the PR, please make sure you do the following - [ ] 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. - [ ] 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`	2 months ago
github-actions[bot]	69e6c4cdbb	Version Packages (#17768) ... 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@5.53.2 ### Patch Changes - fix: update expressions on server deriveds ([#17767](https://github.com/sveltejs/svelte/pull/17767)) - fix: further obfuscate `node:crypto` import from overzealous static analysis ([#17763](https://github.com/sveltejs/svelte/pull/17763)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Conduitry	d75d1f7dbb	fix: further obfuscate `node:crypto` import from overzealous static analysis (#17763) ... Fixes #17762, hopefully	2 months ago
Paolo Ricciuti	6aa7b9c64a	fix: update expressions on server deriveds (#17767) ... Closes #17760	2 months ago
github-actions[bot]	d258f85235	Version Packages (#17755) ... 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@5.53.1 ### Patch Changes - fix: handle shadowed function names correctly ([#17753](https://github.com/sveltejs/svelte/pull/17753)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Simon H	0c7f815143	fix: handle shadowed function names correctly (#17753) ... Fixes #17750 (though the change that causes the issue only surfaced this more general bug) We were not adding the correct scope to function ids. Instead it was part of the function body/params scope, which leads to bugs when the function name is shadowed within the function.	2 months ago
github-actions[bot]	c2fc95a467	Version Packages (#17747) ... 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@5.53.0 ### Minor Changes - feat: allow comments in tags ([#17671](https://github.com/sveltejs/svelte/pull/17671)) - feat: allow error boundaries to work on the server ([#17672](https://github.com/sveltejs/svelte/pull/17672)) ### Patch Changes - fix: use TrustedHTML to test for customizable <select> support, where necessary ([#17743](https://github.com/sveltejs/svelte/pull/17743)) - fix: ensure head effects are kept in the effect tree ([#17746](https://github.com/sveltejs/svelte/pull/17746)) - chore: deactivate current_batch by default in unset_context ([#17738](https://github.com/sveltejs/svelte/pull/17738)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Rich Harris	92e2fc1209	feat: allow comments in tags (#17671) ... Alternative to #17188. I prefer this syntax, it's lighter and feels much more natural to me. For me it's less about commenting things _out_ than about just, well... commenting — I frequently want to do this sort of thing: ```svelte <button // when the user clicks the button, the thing should happen onclick={doTheThing} >click me</button> ``` One difference between this and #17188 is that this doesn't add a node to the AST, just like comments in CSS/JS. Haven't decided if that's desirable or not. I think it's more correct (it's an AST, not a CST; HTML comments are different insofar as they _can_ represent 'real' nodes) but it might be less convenient when (for example) pretty-printing. ### 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` --------- Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>	2 months ago
Simon H	2661513cd3	feat: allow error boundaries to work on the server (#17672) ... This makes error boundaries run on the server if a new `onerror` handler is passed to `render`. `onerror` can either synchronously or asynchronously return a value. It should be a sanitized JSON.stringify-able value so that it can be passed to the client for hydration via a comment. `mount/hydrate` also get the `onerror` property. If no `onerror` is passed to `render` it will just throw just like before, hence this is backwards compatible. This work is important for SvelteKit to allow `+error.svelte` to make use of them and in general to make boundaries properly work during SSR (also see https://github.com/sveltejs/kit/issues/14398). closes #15370 ### 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` --------- Co-authored-by: Rich Harris <rich.harris@vercel.com>	2 months ago
Simon H	582e4443dc	fix: ensure head effects are kept in the effect tree (#17746) ... Fixes #17726 The problem was that the head effect had no "keep me around"-flag, which it needs because its children are not guaranteed to be present immediately - as shown in the related issue, where the child effect is only created once async work has completed. ### 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`	2 months ago
Rich Harris	f8bf9bb461	chore: deactivate current_batch by default in unset_context (#17738) ... Small tweak: except for `{#await ...}` blocks, which are a bit of an anomaly, I'm pretty sure we _always_ want to deactivate the current batch when unsetting context, otherwise it could incorrectly pick up unrelated state changes. There might even be some subtle bugs lurking in the system at present because we _don't_ always do this ### 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`	2 months ago
Rich Harris	696d97ff3e	fix: use TrustedHTML to test for customizable <select> support, where necessary (#17743) ... https://github.com/sveltejs/svelte/pull/17701#issuecomment-3899991195 no test because jsdom	2 months ago
github-actions[bot]	cbf4e246fc	Version Packages (#17742) ... 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@5.52.0 ### Minor Changes - feat: support TrustedHTML in `{@html}` expressions ([#17701](https://github.com/sveltejs/svelte/pull/17701)) ### Patch Changes - fix: repair dynamic component truthy/falsy hydration mismatches ([#17737](https://github.com/sveltejs/svelte/pull/17737)) - fix: re-run non-render-bound deriveds on the server ([#17674](https://github.com/sveltejs/svelte/pull/17674)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Rich Harris	09c4cb5084	fix: re-run non-render-bound deriveds on the server (#17674) ... I tried to bring #14977 up-to-date but it's slipped too far. Also, I wanted to try a slightly different approach. In this PR, deriveds are memoized if they're created during render — in other words if you have something like this... ```svelte <script> let thing = $derived(expensivelyComputeThing()); </script> ``` ...`thing` will only be computed once. This seems correct since the inputs should never change during render. For deriveds created _outside_ render, we re-run the derived each time it is accessed, which fixes #14954. This way, there's still _some_ overhead compared to how deriveds work in the browser (where they only recompute when their dependencies have changed), but only in the rare places where it is necessary. There is one wrinkle: writable deriveds. On `main` these are just regular old variables, which means they can be written to during render. This PR currently preserves that behaviour, but I'm not sure it's desirable. It prevents the values of non-render-bound deriveds from ever updating, and makes no sense in the context of render-bound deriveds since they shouldn't be changing during render _anyway_. So my preference would be to disallow writes to deriveds on the server, but I'm not sure if we would need to consider that a breaking change. Draft because of that question, and also because I think we might be able to tidy up some stuff around class fields. - [x] figure out if we can delete some existing code around derived class fields - [x] figure out what to do about writable deriveds - [x] add a test ### 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`	2 months ago
Rich Harris	be24b0dca7	feat: support TrustedHTML in {@html} expressions (#17701) ... Follow-up to #16271. ## Summary - Allow `{@html}` blocks to accept `TrustedHTML` objects (from TrustedTypes policies) without coercing them to strings - This enables usage like `{@html myPolicy.createHTML(someHTML)}` - Works in regular HTML, SVG, and MathML contexts ## Changes - **`html.js`**: Instead of calling `create_fragment_from_html`, create the wrapper element directly (`<template>`, `<svg>`, or `<math>` depending on context) and assign the value to `innerHTML`. This preserves `TrustedHTML` objects. - **`reconciler.js`**: Removed the `trusted` parameter from `create_fragment_from_html` since it's no longer used by `{@html}` and all remaining callers want trusted HTML. - **`template.js`** and **`snippet.js`**: Removed the second argument from `create_fragment_from_html` calls. ## Notes No tests added because JSDOM doesn't implement TrustedTypes.	2 months ago
Simon H	9f48e7620f	fix: repair dynamic component truthy/falsy hydration mismatches (#17737) ... Fixes #17735 Use the if/else hydration markers to know what "branch" (component or no component) was rendered, and repair if differing. ### 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`	2 months ago
github-actions[bot]	8ea33bf7fe	Version Packages (#17740) ... 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@5.51.5 ### Patch Changes - fix: check to make sure `svelte:element` tags are valid during SSR ([`73098bb26c6f06e7fd1b0746d817d2c5ee90755f`](73098bb26c)) - fix: misc option escaping and backwards compatibility ([#17741](https://github.com/sveltejs/svelte/pull/17741)) - fix: strip event handlers during SSR ([`a0c7f289156e9fafaeaf5ca14af6c06fe9b9eae5`](a0c7f28915)) - fix: replace usage of `for in` with `for of Object.keys` ([`f89c7ddd7eebaa1ef3cc540400bec2c9140b330c`](f89c7ddd7e)) - fix: always escape option body in SSR ([`f7c80da18c215e3727c2a611b0b8744cc6e504c5`](f7c80da18c)) - chore: upgrade `devalue` ([#17739](https://github.com/sveltejs/svelte/pull/17739)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>	2 months ago
Elliott Johnson	f855a0b770	fix: misc option escaping and backwards compatibility (#17741) ... ### Before submitting the PR, please make sure you do the following - [ ] 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 - [ ] Prefix your PR title with `feat:`, `fix:`, `chore:`, or `docs:`. - [ ] This message body should clearly illustrate what problems it solves. - [ ] Ideally, include a test that fails without this PR but passes with it. - [ ] 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`	2 months ago
Elliott Johnson	781052eeab	chore: upgrade `devalue` (#17739) ... ### Before submitting the PR, please make sure you do the following - [ ] 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 - [ ] Prefix your PR title with `feat:`, `fix:`, `chore:`, or `docs:`. - [ ] This message body should clearly illustrate what problems it solves. - [ ] Ideally, include a test that fails without this PR but passes with it. - [ ] 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`	2 months ago
Paolo Ricciuti	f7c80da18c	Merge commit from fork	2 months ago
Elliott Johnson	a0c7f28915	Merge commit from fork ... * fix: strip event handlers during SSR * whatever conduitry you're not that cool * tweak	2 months ago