fix(#3319): add regression test for component children

packages/astro/test/astro-markdown.test.js

@@ -42,6 +42,13 @@ describe('Astro Markdown', () => {
 		expect($('h1').attr("id")).to.equal('my-blog-post');
 	});
 
+	it('Correctly handles component children in markdown pages (#3319)', async () => {
+		const html = await fixture.readFile('/children/index.html');
+
+		console.log(html);
+		expect(html).not.to.contain('<p></p>');
+	});
+
 	it('Can load more complex jsxy stuff', async () => {
 		const html = await fixture.readFile('/complex/index.html');
 		const $ = cheerio.load(html);

packages/astro/test/fixtures/astro-markdown/src/components/TextBlock.jsx

@@ -0,0 +1,20 @@
+import { h } from 'preact';
+
+const TextBlock = ({
+  title,
+  children,
+  noPadding = false,
+}) => {
+  return (
+    <div
+      className={`${
+        noPadding ? "" : "md:px-2 lg:px-4"
+      } flex-1 prose prose-headings:font-grotesk`}
+    >
+      <h3>{title}</h3>
+      <p>{children}</p>
+    </div>
+  );
+};
+
+export default TextBlock;

packages/astro/test/fixtures/astro-markdown/src/pages/children.md

@@ -0,0 +1,12 @@
+---
+setup: import TextBlock from '../components/TextBlock'
+---
+{/* https://github.com/withastro/astro/issues/3319 */}
+
+<TextBlock title="Hello world!" noPadding>
+  <ul class="not-prose">
+    <li>A</li>
+    <li>B</li>
+    <li>C</li>
+  </ul>
+</TextBlock>