vite-plugin-mdx-postprocess.ts — astro Source File

Source Code

import type { AstroConfig } from 'astro';
import { type ExportSpecifier, type ImportSpecifier, parse } from 'es-module-lexer';
import type { Plugin } from 'vite';
import {
	ASTRO_IMAGE_ELEMENT,
	ASTRO_IMAGE_IMPORT,
	USES_ASTRO_IMAGE_FLAG,
} from './rehype-images-to-component.js';
import { type FileInfo, getFileInfo } from './utils.js';

const underscoreFragmentImportRegex = /[\s,{]_Fragment[\s,}]/;
const astroTagComponentImportRegex = /[\s,{]__astro_tag_component__[\s,}]/;

// These transforms must happen *after* JSX runtime transformations
export function vitePluginMdxPostprocess(astroConfig: AstroConfig): Plugin {
	return {
		name: '@astrojs/mdx-postprocess',
		transform: {
			filter: {
				id: /\.mdx$/,
			},
			handler(code, id) {
				const fileInfo = getFileInfo(id, astroConfig);
				const [imports, exports] = parse(code);

				// Call a series of functions that transform the code
				code = injectUnderscoreFragmentImport(code, imports);
				code = injectMetadataExports(code, exports, fileInfo);
				code = transformContentExport(code, exports);
				code = annotateContentExport(
					code,
					id,
					this.environment.name === 'ssr' || this.environment.name === 'prerender',
					imports,
				);

				// The code transformations above are append-only, so the line/column mappings are the same
				// and we can omit the sourcemap for performance.
				return { code, map: null };
			},
		},
	};
}

/**
 * Inject `Fragment` identifier import if not already present.
 */
function injectUnderscoreFragmentImport(code: string, imports: readonly ImportSpecifier[]) {
	if (!isSpecifierImported(code, imports, underscoreFragmentImportRegex, 'astro/jsx-runtime')) {
		code += `\nimport { Fragment as _Fragment } from 'astro/jsx-runtime';`;
	}
	return code;
}

/**
 * Inject MDX metadata as exports of the module.
 */
function injectMetadataExports(
	code: string,
	exports: readonly ExportSpecifier[],
// ... (97 more lines)