Fix head content parsing issue

[HiDeoo]

Changes

• Closes Closing HTML tag getting removed when there's a component above #957

This PR fixes an issue with head content parsing when such content is defined in a component that first renders another component before other elements like <title> when using an expression for the title.

When first encoutering a start tag token for a component before any HTML, we switch to the "in body" insertion mode. After that, when we encounter a start tag token for some head related tags, we use the "in head" insertion mode to parse them correctly. Altho, when we later encounter the associated end tag token, we do not switch back to the "in head" insertion mode, which causes invalid markup to be generated.

For example, considering the following Astro component supposed to be rendered in the head:

---
import Analytics from '../components/Analytics.astro';
---
<Analytics />
<title>{title}</title>
<meta name="description" content="a description" />

The generated code before this fix was invalid (notice the meta tag is inside the title tag):

return $$render`${$$renderComponent($$result, "Analytics", Analytics, {})}
<title>${title}
<meta name="description" content="a description"></title>`;

Testing

I added a new print test case for a similar scenario as the one described in the issue which generates a snapshot file with the expected output after the fix.

Docs

This is a bug fix only, so no docs were added or updated.

[changeset-bot]

🦋 Changeset detected

Latest commit: baba655

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

This PR includes changesets to release 1 package

Name	Type
@astrojs/compiler	Patch

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[ematipico]

Great fix!