website/node_modules/astro-expressive-code/components/Code.astro

---
import { addClassName, toHtml } from 'rehype-expressive-code/hast'
import { getPageData } from './page-data'
import { getRenderer } from './renderer'
import type { CodeProps as Props, MarkerValueType } from './types'

function formatMessage(...messageParts: string[]) {
	return messageParts.map((part) => part.replace(/\s+/g, ' ')).join('\n\n')
}

async function renderToHtml() {
	const defaultSlotContent = await Astro.slots.render('default')
	if (defaultSlotContent?.trim().length) {
		throw new Error(
			formatMessage(
				`Unsupported child content was found inside the component.
				The code to render must be passed to the \`code\` prop as a string.`,
				`Please remove the following child content:\n${defaultSlotContent}`
			)
		)
	}

	let { code, lang = '', meta = '', locale, class: className, ...props } = Astro.props

	if (!code || !code.trim().length) {
		throw new Error('Missing code to render. The `code` prop must be set to a non-empty string.')
	}

	const pageData = getPageData(Astro.request)
	// Note: It's important to store the incremented index in a local variable immediately,
	// as the `pageData` object is shared between all components on the current page
	// and can be changed by other Code components during the `await` calls below
	const groupIndex = ++pageData.blockGroupIndex

	const renderer = await getRenderer()

	const { renderedGroupAst } = await renderer.ec.render({
		code,
		language: lang,
		meta,
		locale,
		parentDocument: {
			positionInDocument: {
				groupIndex,
			},
		},
		props,
	})

	if (renderedGroupAst?.type === 'element') {
		if (className) {
			const classNames = className.split(' ')
			classNames.forEach((className) => addClassName(renderedGroupAst, className))
		}
	}

	return toHtml(renderedGroupAst)
}

let html = ''
try {
	html = await renderToHtml()
} catch (err) {
	const prefix = `Failed to render a \`<Code>\` component on page ${Astro.request.url}:`
	const error = err instanceof Error ? err : new Error(String(err))
	throw new Error(`${prefix}\n\n${error.message}`, { cause: error })
}
---

<Fragment set:html={html} />