1 files changed, 40 insertions, 0 deletions
diff --git a/packages/integrations/mdx/test/mdx-frontmatter-injection.test.js b/packages/integrations/mdx/test/mdx-frontmatter-injection.test.js
new file mode 100644
index 000000000..ae1d485bb
--- /dev/null
+++ b/packages/integrations/mdx/test/mdx-frontmatter-injection.test.js
@@ -0,0 +1,40 @@
+import { expect } from 'chai';
+import { loadFixture } from '../../../astro/test/test-utils.js';
+
+const FIXTURE_ROOT = new URL('./fixtures/mdx-frontmatter-injection/', import.meta.url);
+
+describe('MDX frontmatter injection', () => {
+	let fixture;
+
+	before(async () => {
+		fixture = await loadFixture({
+			root: FIXTURE_ROOT,
+		});
+		await fixture.build();
+	});
+
+	it('remark supports custom vfile data - get title', async () => {
+		const frontmatterByPage = JSON.parse(await fixture.readFile('/glob.json'));
+		const titles = frontmatterByPage.map((frontmatter = {}) => frontmatter.title);
+		expect(titles).to.contain('Page 1');
+		expect(titles).to.contain('Page 2');
+	});
+
+	it('rehype supports custom vfile data - reading time', async () => {
+		const frontmatterByPage = JSON.parse(await fixture.readFile('/glob.json'));
+		const readingTimes = frontmatterByPage.map((frontmatter = {}) => frontmatter.injectedReadingTime);
+		expect(readingTimes.length).to.be.greaterThan(0);
+		for (let readingTime of readingTimes) {
+			expect(readingTime).to.not.be.null;
+			expect(readingTime.text).match(/^\d+ min read/);
+		}
+	});
+
+	it('overrides injected frontmatter with user frontmatter', async () => {
+		const frontmatterByPage = JSON.parse(await fixture.readFile('/glob.json'));
+		const readingTimes = frontmatterByPage.map((frontmatter = {}) => frontmatter.injectedReadingTime?.text);
+		const titles = frontmatterByPage.map((frontmatter = {}) => frontmatter.title);
+		expect(titles).to.contain('Overridden title');
+		expect(readingTimes).to.contain('1000 min read');
+	});
+});