astro/packages/integrations/markdoc/test/syntax-highlighting.test.js

import { parseHTML } from 'linkedom';
import { expect } from 'chai';
import Markdoc from '@markdoc/markdoc';
import shiki from '../dist/extensions/shiki.js';
import prism from '../dist/extensions/prism.js';
import { setupConfig } from '../dist/runtime.js';
import { isHTMLString } from 'astro/runtime/server/index.js';

const entry = `
\`\`\`ts
const highlighting = true;
\`\`\`

\`\`\`css
.highlighting {
	color: red;
}
\`\`\`
`;

describe('Markdoc - syntax highlighting', () => {
	describe('shiki', () => {
		it('transforms with defaults', async () => {
			const ast = Markdoc.parse(entry);
			const content = Markdoc.transform(ast, await getConfigExtendingShiki());

			expect(content.children).to.have.lengthOf(2);
			for (const codeBlock of content.children) {
				expect(isHTMLString(codeBlock)).to.be.true;

				const pre = parsePreTag(codeBlock);
				expect(pre.classList).to.include('astro-code');
				expect(pre.classList).to.include('github-dark');
			}
		});
		it('transforms with `theme` property', async () => {
			const ast = Markdoc.parse(entry);
			const content = Markdoc.transform(
				ast,
				await getConfigExtendingShiki({
					theme: 'dracula',
				})
			);
			expect(content.children).to.have.lengthOf(2);
			for (const codeBlock of content.children) {
				expect(isHTMLString(codeBlock)).to.be.true;

				const pre = parsePreTag(codeBlock);
				expect(pre.classList).to.include('astro-code');
				expect(pre.classList).to.include('dracula');
			}
		});
		it('transforms with `wrap` property', async () => {
			const ast = Markdoc.parse(entry);
			const content = Markdoc.transform(
				ast,
				await getConfigExtendingShiki({
					wrap: true,
				})
			);
			expect(content.children).to.have.lengthOf(2);
			for (const codeBlock of content.children) {
				expect(isHTMLString(codeBlock)).to.be.true;

				const pre = parsePreTag(codeBlock);
				expect(pre.getAttribute('style')).to.include('white-space: pre-wrap');
				expect(pre.getAttribute('style')).to.include('word-wrap: break-word');
			}
		});
	});

	describe('prism', () => {
		it('transforms', async () => {
			const ast = Markdoc.parse(entry);
			const config = await setupConfig({
				extends: [prism()],
			});
			const content = Markdoc.transform(ast, config);

			expect(content.children).to.have.lengthOf(2);
			const [tsBlock, cssBlock] = content.children;

			expect(isHTMLString(tsBlock)).to.be.true;
			expect(isHTMLString(cssBlock)).to.be.true;

			const preTs = parsePreTag(tsBlock);
			expect(preTs.classList).to.include('language-ts');

			const preCss = parsePreTag(cssBlock);
			expect(preCss.classList).to.include('language-css');
		});
	});
});

/**
 * @param {import('astro').ShikiConfig} config
 * @returns {import('../src/config.js').AstroMarkdocConfig}
 */
async function getConfigExtendingShiki(config) {
	return await setupConfig({
		extends: [shiki(config)],
	});
}

/**
 * @param {string} html
 * @returns {HTMLPreElement}
 */
function parsePreTag(html) {
	const { document } = parseHTML(html);
	const pre = document.querySelector('pre');
	expect(pre).to.exist;
	return pre;
}