[MDX] Add Prism and Shiki support (#4002)

* deps: add rehype-prism, shiki, rehype-pretty-code

* wip: apply rehype plugins depending on config

* wip: cherry-pick jsx-runtime fix?

* deps: rehype-pretty-code -> shiki-twoslash, add rehype-raw

* wip: add jsx-runtime fix

* feat: get shiki working!

* deps: add @astrojs/prism, prismjs, unist-util-visit

* feat: add prism support

* example: add small syntax highlight demo to with-mdx

* deps: remove rehype-prism

* chore: remove unused async

* chore: add .test.js to all mdx tests

* test: shiki, shikiConfig, prism

* fix: remove "is:raw" from prism output

* docs: add syntax highlighting section

* chore: add changeset

* nit: "Shiki config" -> Shiki config

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

* Revert "wip: add jsx-runtime fix"

This reverts commit 07f4528f449281afb7bbc154b09292244795a183.

* docs: link to integration README from example

Co-authored-by: Nate Moore <nate@astro.build>
Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

1 files changed, 45 insertions, 0 deletions

diff --git a/packages/integrations/mdx/test/mdx-frontmatter.test.js b/packages/integrations/mdx/test/mdx-frontmatter.test.js
new file mode 100644
index 000000000..3021f926f
--- /dev/null
+++ b/packages/integrations/mdx/test/mdx-frontmatter.test.js
@@ -0,0 +1,45 @@
+import mdx from '@astrojs/mdx';
+
+import { expect } from 'chai';
+import { loadFixture } from '../../../astro/test/test-utils.js';
+
+const FIXTURE_ROOT = new URL('./fixtures/mdx-frontmatter/', import.meta.url);
+
+describe('MDX frontmatter', () => {
+	it('builds when "frontmatter.property" is in JSX expression', async () => {
+		const fixture = await loadFixture({
+			root: FIXTURE_ROOT,
+			integrations: [mdx()],
+		});
+		await fixture.build();
+		expect(true).to.equal(true);
+	});
+
+	it('extracts frontmatter to "frontmatter" export', async () => {
+		const fixture = await loadFixture({
+			root: FIXTURE_ROOT,
+			integrations: [mdx()],
+		});
+		await fixture.build();
+
+		const { titles } = JSON.parse(await fixture.readFile('/glob.json'));
+		expect(titles).to.include('Using YAML frontmatter');
+	});
+
+	it('extracts frontmatter to "customFrontmatter" export when configured', async () => {
+		const fixture = await loadFixture({
+			root: new URL('./fixtures/mdx-custom-frontmatter-name/', import.meta.url),
+			integrations: [
+				mdx({
+					frontmatterOptions: {
+						name: 'customFrontmatter',
+					},
+				}),
+			],
+		});
+		await fixture.build();
+
+		const { titles } = JSON.parse(await fixture.readFile('/glob.json'));
+		expect(titles).to.include('Using YAML frontmatter');
+	});
+});