fix(html_formatter): match prettier for svelte each as destructuring …

[ruidosujeira]

Summary

This PR fixes two formatting inconsistencies between Biome's Svelte/HTML formatter and Prettier, as reported in #10839.

Closed #10839

Changes

Array destructuring in {#each} blocks
Removed unnecessary spaces inside square brackets when using array destructuring.svelte.

<!-- Before -->
{#each list as [ item, title ]}

<!-- After -->
{#each list as [item, title]}
Bind with getter/setter functions
Improved formatting of bind:prop={get, set} expressions to allow proper line breaking when the value is complex.svelte<!-- Now formats correctly -->
bind:clientWidth={
    null,
    (width) => { ... }
}

These changes make Biome's output match Prettier's behavior for the reported cases.
Changeset: fix-svelte-html-each-as-and-bind.md (patch)

Test Plan

All existing Svelte snapshot tests are passing:

cargo test -p biome_html_formatter --test spec_tests -- svelte

Ran just f to verify formatting consistency.

cargo clippy -p biome_html_formatter -- -D warnings (clean).

Updated snapshots:

each_with_destructuring.svelte.snap
each_with_rename_binding.svelte.snap

Docs

No documentation changes needed (formatter behavior only).

[changeset-bot]

🦋 Changeset detected

Latest commit: fbb4e28

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 13 packages

Name	Type
@biomejs/biome	Patch
@biomejs/cli-win32-x64	Patch
@biomejs/cli-win32-arm64	Patch
@biomejs/cli-darwin-x64	Patch
@biomejs/cli-darwin-arm64	Patch
@biomejs/cli-linux-x64	Patch
@biomejs/cli-linux-arm64	Patch
@biomejs/cli-linux-x64-musl	Patch
@biomejs/cli-linux-arm64-musl	Patch
@biomejs/wasm-web	Patch
@biomejs/wasm-bundler	Patch
@biomejs/wasm-nodejs	Patch
@biomejs/backend-jsonrpc	Patch

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[coderabbitai]

Walkthrough

Updates Svelte HTML formatting for array destructuring in {#each} blocks by removing spaces inside square brackets. Adjusts multiline bind function expression formatting to conditionally break and indent getter, setter, and function body content. Adds a Svelte fixture covering both cases and records a patch changeset referencing issue #10839.

Possibly related PRs

• biomejs/biome#9692: Covers related Svelte nested #each array destructuring support and formatting.

Suggested reviewers: dyc3

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title is specific and related to the formatter changes, though it only highlights one of the two fixes.
Description check	✅ Passed	The description matches the Svelte formatter fixes and changeset described in the diff.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[codspeed-hq]

Merging this PR will not alter performance

✅ 67 untouched benchmarks
⏩ 206 skipped benchmarks¹

---

_{Comparing ruidosujeira:fix/svelte-html-formatter-10839 (fbb4e28) with main (c9acb25)}

Footnotes

1. 206 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[ematipico]

Can you please add tests that show that the softline break works as expected?

[dyc3]

Code is good, fine to merge as is, but this doesn't fully resolve #10839. There's more formatting mismatches in that issue's repro.

[ematipico]

Actually, the fix isn't right now that I look at it. Prettier doesn't emit a softline. It just prints without space between brackets

[ruidosujeira]

@dyc3 @ematipico

Thank you both for the fast reviews and detailed feedback! 🙏
I understand now, there are still more formatting mismatches in the original repro of #10839 that this PR didn't cover yet.
The current approach with soft_block_indent/softline is not matching Prettier's simpler behavior (it just prints without space between brackets, no softline).
I'll update the PR shortly with:
A more minimal fix for the destructuring (just remove the spaces inside [], exactly as Prettier does).
Coverage for the remaining mismatches from the issue's repro.
The requested tests for the bind behavior

[ruidosujeira]

Thanks for the feedback, and apologies for leaving this without a proper follow-up.

After reviewing the full reproduction and comparing the output with Prettier again, I agree that my description overstated what this PR currently fixes. The problem hasn't been resolved yet, and I'm working on it.

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In
`@crates/biome_html_formatter/src/svelte/auxiliary/bind_function_binding_expression.rs`:
- Around line 30-37: Move set.format() into the existing indent block in the
binding expression formatter, alongside get.format(), comma_token.format(), and
the line-break elements. Preserve the current ordering so set remains formatted
after the separator while inheriting the nested indentation when the group
breaks.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

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📥 Commits

Reviewing files that changed from the base of the PR and between 9ea537c and 218ab10.

⛔ Files ignored due to path filters (1)

• crates/biome_html_formatter/tests/specs/html/svelte/issue_10839.svelte.snap is excluded by !**/*.snap and included by **

📒 Files selected for processing (3)

• .changeset/fix-svelte-html-each-as-and-bind.md
• crates/biome_html_formatter/src/svelte/auxiliary/bind_function_binding_expression.rs
• crates/biome_html_formatter/tests/specs/html/svelte/issue_10839.svelte

🚧 Files skipped from review as they are similar to previous changes (1)

• .changeset/fix-svelte-html-each-as-and-bind.md

[ruidosujeira]

I’ve updated the PR with a smaller and cleaner implementation:

• removed the extra spaces inside Svelte {#each} array destructuring without introducing softline;
• adjusted bind:prop={get, set} so short expressions remain inline and long expressions break with the getter, setter, and function body correctly indented;
• added coverage for the remaining mismatches from the original 📝 svelte html formatter formats differently each as and bind functions from prettier #10839 reproduction, including nested destructuring and multiline bind functions;
• removed the redundant test fixture and kept the changes narrowly scoped.

The previous indentation issue reported by CodeRabbit was also fixed, and the snapshot now reflects the expected output.

Could you please take another look when possible?