Simplified head injection (#6034)

* Simplified head injection

* Make renderHead also yield an instruction

* Add changeset

* Add mdx test

1 files changed, 33 insertions, 0 deletions

diff --git a/packages/integrations/mdx/test/css-head-mdx.test.js b/packages/integrations/mdx/test/css-head-mdx.test.js
new file mode 100644
index 000000000..a6492c3ba
--- /dev/null
+++ b/packages/integrations/mdx/test/css-head-mdx.test.js
@@ -0,0 +1,33 @@
+import mdx from '@astrojs/mdx';
+
+import { expect } from 'chai';
+import { parseHTML } from 'linkedom';
+import { loadFixture } from '../../../astro/test/test-utils.js';
+
+describe('Head injection w/ MDX', () => {
+	let fixture;
+
+	before(async () => {
+		fixture = await loadFixture({
+			root: new URL('./fixtures/css-head-mdx/', import.meta.url),
+			integrations: [mdx()],
+		});
+	});
+
+	describe('build', () => {
+		before(async () => {
+			await fixture.build();
+		});
+
+		it('only injects contents into head', async () => {
+			const html = await fixture.readFile('/indexThree/index.html');
+			const { document } = parseHTML(html);
+
+			const links = document.querySelectorAll('link[rel=stylesheet]');
+			expect(links).to.have.a.lengthOf(1);
+
+			const scripts = document.querySelectorAll('script[type=module]');
+			expect(scripts).to.have.a.lengthOf(1);
+		});
+	});
+});