[b84330808]

closes #12727

When enhanced:img gets an image imported in the script (src={example}), its size is only known at runtime, so the plugin passes {example.img.w} and {example.img.h} to serialize_img_attributes. If the user sets only width (or only height), the other one is computed with parseInt on those strings, which gives height=NaN (or width=NaN).

In that case the plugin now outputs an expression that does the same calculation at runtime, for example height={Math.round((example.img.h * 280) / example.img.w)}. Static images keep the number computed at build time.

The snapshot test gets a width-only and a height-only case with an imported image, and now checks that the output contains no NaN. It fails without this change.

I used Claude Code to write this change.

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I ran the @sveltejs/enhanced-img unit tests and its check, plus oxfmt --check and ESLint on the changed files, not the full pnpm test.

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[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from ed86c66:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/ed86c665756b63876f126f8c46a18a1bac1f7afd

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/17499

Note

This PR is from a fork. A maintainer must approve approve each commit before it can be built and installed.

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🦋 Changeset detected

Latest commit: ed86c66

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

This PR includes changesets to release 1 package

Name	Type
@sveltejs/enhanced-img	Patch

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