Format failed with `attribute_empty_shorthand` for Snippet with attachment

[korywka]

Describe the bug

prettier stops formatting when snippet inside tag with attach tag with attribute_empty_shorthand error. svelte check gives no error and this code is compiled successfully.

Reproduction

	<UIButton href="/filters" variant="blur" badge={filtersBadge}>
		{#snippet icon()}
			<svg {@attach svg('/filter.svg')} />
		{/snippet}
	</UIButton>

Logs

2025-10-13T02:15:07+02:00 ERROR [project::lsp_store] Formatting failed: default prettier instance failed to format buffer: attribute_empty_shorthand: Attribute shorthand cannot be empty
https://svelte.dev/e/attribute_empty_shorthand
(unknown):6:8
4:   <UIButton href="/filters" variant="blur" badge={filtersBadge}>
5:     {#snippet icon()}
6:       <svg {@attach svg('/filter.svg')} />
              ^
7:     {/snippet}
8:   </UIButton>
While handling prettier request: {"jsonrpc":"2.0","id":39,"method":"prettier/format","params":{"text":"..snip..","options":{"plugins":["/Users/~/Library/Application Support/Zed/prettier/node_modules/prettier-plugin-svelte/plugin.js"],"parser":null,"filepath":"/Users/~/git/~web/src/components/menu/Menu.svelte","prettierOptions":{"printWidth":120,"useTabs":true,"tabWidth":2},"ignorePath":null

System Info

nodejs

Severity

annoyance

[korywka]

The bug is only in Zed editor but not VSCode. Looks like some old language server or something.