[feat] support for other aliases in package command

.changeset/weak-hotels-hang.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/package': patch
+---
+
+[feat] Support aliases set through `kit.alias`

packages/package/src/config.js

@@ -26,6 +26,7 @@ export async function load_config({ cwd = process.cwd() } = {}) {
 function process_config(config, { cwd = process.cwd() } = {}) {
 	return {
 		extensions: config.extensions ?? ['.svelte'],
+		kit: config.kit,
 		package: {
 			source: path.resolve(cwd, config.kit?.files?.lib ?? config.package?.source ?? 'src/lib'),
 			dir: config.package?.dir ?? 'package',

packages/package/src/utils.js

@@ -16,22 +16,26 @@ import { posixify, mkdirp, walk } from './filesystem.js';
  * @returns {string}
  */
 export function resolve_lib_alias(file, content, config) {
+	const aliases = { $lib: path.resolve(config.package.source), ...(config.kit?.alias ?? {}) };
+
 	/**
 	 * @param {string} match
 	 * @param {string} _
 	 * @param {string} import_path
 	 */
 	const replace_import_path = (match, _, import_path) => {
-		if (!import_path.startsWith('$lib/')) {
-			return match;
+		for (const [alias, value] of Object.entries(aliases)) {
+			if (!import_path.startsWith(alias)) continue;
+
+			const full_path = path.join(config.package.source, file);
+			const full_import_path = path.join(value, import_path.slice(alias.length));
+			let resolved = posixify(path.relative(path.dirname(full_path), full_import_path));
+			resolved = resolved.startsWith('.') ? resolved : './' + resolved;
+			return match.replace(import_path, resolved);
 		}
-
-		const full_path = path.join(config.package.source, file);
-		const full_import_path = path.join(config.package.source, import_path.slice('$lib/'.length));
-		let resolved = posixify(path.relative(path.dirname(full_path), full_import_path));
-		resolved = resolved.startsWith('.') ? resolved : './' + resolved;
-		return match.replace(import_path, resolved);
+		return match;
 	};
+
 	content = content.replace(/from\s+('|")([^"';,]+?)\1/g, replace_import_path);
 	content = content.replace(/import\s*\(\s*('|")([^"';,]+?)\1\s*\)/g, replace_import_path);
 	return content;

packages/package/test/fixtures/resolve-alias/expected/Test.svelte

@@ -1,4 +1,6 @@
 <script>
     import { foo } from './sub/foo';
+		import { util } from './utils';
     export let bar = foo;
+		util();
 </script>

packages/package/test/fixtures/resolve-alias/expected/package.json

@@ -7,10 +7,11 @@
 	"exports": {
 		"./package.json": "./package.json",
 		"./Test.svelte": "./Test.svelte",
+		"./utils": "./utils/index.js",
 		".": "./index.js",
 		"./baz": "./baz.js",
 		"./sub/bar": "./sub/bar.js",
 		"./sub/foo": "./sub/foo.js"
 	},
 	"svelte": "./index.js"
-}
+}

packages/package/test/fixtures/resolve-alias/expected/utils/index.d.ts

@@ -0,0 +1 @@
+export declare const util: () => void;

packages/package/test/fixtures/resolve-alias/expected/utils/index.js

@@ -0,0 +1 @@
+export const util = () => { };

packages/package/test/fixtures/resolve-alias/src/lib/Test.svelte

@@ -1,5 +1,8 @@
 <script lang="ts">
     import { foo } from '$lib/sub/foo';
+    import { util } from '$utils';
 
     export let bar = foo;
+
+		util();
 </script>

packages/package/test/fixtures/resolve-alias/src/lib/utils/index.ts

@@ -0,0 +1 @@
+export const util = () => {};

packages/package/test/fixtures/resolve-alias/svelte.config.js

@@ -1,5 +1,15 @@
 import preprocess from 'svelte-preprocess';
+import { fileURLToPath } from 'url';
+import path from 'path';
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.join(__filename, '..');
 
 export default {
-	preprocess: preprocess()
+	preprocess: preprocess(),
+	kit: {
+		alias: {
+			$utils: path.resolve(__dirname, './src/lib/utils')
+		}
+	}
 };

packages/package/test/fixtures/resolve-alias/tsconfig.json

@@ -5,7 +5,8 @@
 		"checkJs": true,
 		"baseUrl": ".",
 		"paths": {
-			"$lib/*": ["./src/lib/*"]
+			"$lib/*": ["./src/lib/*"],
+			"$utils/*": ["./src/lib/utils/*"]
 		}
 	},
 	"include": ["src/**/*.d.ts", "src/**/*.js", "src/**/*.svelte"]