1 files changed, 115 insertions, 0 deletions
diff --git a/scripts/cmd/prebuild.js b/scripts/cmd/prebuild.js
new file mode 100644
index 000000000..7c4174abf
--- /dev/null
+++ b/scripts/cmd/prebuild.js
@@ -0,0 +1,115 @@
+import fs from 'node:fs';
+import path from 'node:path';
+import { fileURLToPath, pathToFileURL } from 'node:url';
+import esbuild from 'esbuild';
+import glob from 'fast-glob';
+import { red } from 'kleur/colors';
+
+function escapeTemplateLiterals(str) {
+	return str.replace(/\`/g, '\\`').replace(/\$\{/g, '\\${');
+}
+
+export default async function prebuild(...args) {
+	let buildToString = args.indexOf('--to-string');
+	if (buildToString !== -1) {
+		args.splice(buildToString, 1);
+		buildToString = true;
+	}
+	let minify = true;
+	let minifyIdx = args.indexOf('--no-minify');
+	if (minifyIdx !== -1) {
+		minify = false;
+		args.splice(minifyIdx, 1);
+	}
+
+	let patterns = args;
+	// NOTE: absolute paths returned are forward slashes on windows
+	let entryPoints = [].concat(
+		...(await Promise.all(
+			patterns.map((pattern) => glob(pattern, { onlyFiles: true, absolute: true })),
+		)),
+	);
+
+	function getPrebuildURL(entryfilepath, dev = false) {
+		const entryURL = pathToFileURL(entryfilepath);
+		const basename = path.basename(entryfilepath);
+		const ext = path.extname(entryfilepath);
+		const name = basename.slice(0, basename.indexOf(ext));
+		const outname = dev ? `${name}.prebuilt-dev${ext}` : `${name}.prebuilt${ext}`;
+		const outURL = new URL('./' + outname, entryURL);
+		return outURL;
+	}
+
+	async function prebuildFile(filepath) {
+		let tscode = await fs.promises.readFile(filepath, 'utf-8');
+		// If we're bundling a client directive, modify the code to match `packages/astro/src/core/client-directive/build.ts`.
+		// If updating this code, make sure to also update that file.
+		if (filepath.includes('runtime/client')) {
+			// `export default xxxDirective` is a convention used in the current client directives that we use
+			// to make sure we bundle this right. We'll error below if this convention isn't followed.
+			const newTscode = tscode.replace(
+				/export default (.*?)Directive/,
+				(_, name) =>
+					`(self.Astro || (self.Astro = {})).${name} = ${name}Directive;window.dispatchEvent(new Event('astro:${name}'))`,
+			);
+			if (newTscode === tscode) {
+				console.error(
+					red(
+						`${filepath} doesn't follow the \`export default xxxDirective\` convention. The prebuilt output may be wrong. ` +
+							`For more information, check out ${fileURLToPath(import.meta.url)}`,
+					),
+				);
+			}
+			tscode = newTscode;
+		}
+
+		const esbuildOptions = {
+			stdin: {
+				contents: tscode,
+				resolveDir: path.dirname(filepath),
+				loader: 'ts',
+				sourcefile: filepath,
+			},
+			format: 'iife',
+			target: ['es2018'],
+			minify,
+			bundle: true,
+			write: false,
+		};
+
+		const results = await Promise.all(
+			[
+				{
+					build: await esbuild.build(esbuildOptions),
+					dev: false,
+				},
+				filepath.includes('astro-island')
+					? {
+							build: await esbuild.build({
+								...esbuildOptions,
+								define: { 'process.env.NODE_ENV': '"development"' },
+							}),
+							dev: true,
+						}
+					: undefined,
+			].filter((entry) => entry),
+		);
+
+		for (const result of results) {
+			const code = result.build.outputFiles[0].text.trim();
+			const rootURL = new URL('../../', import.meta.url);
+			const rel = path.relative(fileURLToPath(rootURL), filepath);
+			const mod = `/**
+ * This file is prebuilt from ${rel}
+ * Do not edit this directly, but instead edit that file and rerun the prebuild
+ * to generate this file.
+ */
+
+export default \`${escapeTemplateLiterals(code)}\`;`;
+			const url = getPrebuildURL(filepath, result.dev);
+			await fs.promises.writeFile(url, mod, 'utf-8');
+		}
+	}
+
+	await Promise.all(entryPoints.map(prebuildFile));
+}