feat: support importing package with ts export (#10)

Author: privatenumber

src/loaders.ts

@@ -17,17 +17,19 @@ const sourcemaps = installSourceMapSupport();
 const tsconfig = getTsconfig();
 const tsconfigRaw = tsconfig?.config;
 
+type Resolved = {
+	url: string;
+	format: ModuleFormat;
+};
+
 type resolve = (
 	specifier: string,
 	context: {
 		conditions: string[];
 		parentURL: string | undefined;
 	},
 	defaultResolve: resolve,
-) => MaybePromise<{
-	url: string;
-	format: ModuleFormat;
-}>;
+) => MaybePromise<Resolved>;
 
 const hasExtensionPattern = /\.\w+$/;
 
@@ -69,25 +71,9 @@ export const resolve: resolve = async function (
 		}
 	}
 
-	if (tsExtensionsPattern.test(specifier)) {
-		const resolved = await defaultResolve(specifier, context, defaultResolve);
-		const format = getFormatFromExtension(resolved.url) ?? await getPackageType(resolved.url);
-
-		return {
-			...resolved,
-			format,
-		};
-	}
-
-	if (specifier.endsWith('.json')) {
-		return {
-			...(await defaultResolve(specifier, context, defaultResolve)),
-			format: 'json',
-		};
-	}
-
+	let resolved: Resolved;
 	try {
-		return await defaultResolve(specifier, context, defaultResolve);
+		resolved = await defaultResolve(specifier, context, defaultResolve);
 	} catch (error) {
 		if (error instanceof Error) {
 			if ((error as any).code === 'ERR_UNSUPPORTED_DIR_IMPORT') {
@@ -114,6 +100,23 @@ export const resolve: resolve = async function (
 
 		throw error;
 	}
+
+	if (resolved.url.endsWith('.json')) {
+		return {
+			...resolved,
+			format: 'json',
+		};
+	}
+
+	if (tsExtensionsPattern.test(resolved.url)) {
+		const format = getFormatFromExtension(resolved.url) ?? await getPackageType(resolved.url);
+		return {
+			...resolved,
+			format,
+		};
+	}
+
+	return resolved;
 };
 
 type load = (
@@ -149,12 +152,7 @@ export const load: load = async function (
 
 	const loaded = await defaultLoad(url, context, defaultLoad);
 
-	if (
-		!loaded.source
-
-		// node_modules don't need to be transformed
-		|| url.includes('/node_modules/')
-	) {
+	if (!loaded.source) {
 		return loaded;
 	}
 

tests/fixtures/package-module/node_modules/package-module/ts.ts

@@ -0,0 +1,20 @@
+import { testSuite, expect } from 'manten';
+import type { NodeApis } from '../../utils/node-with-loader';
+
+export default testSuite(async ({ describe }, node: NodeApis) => {
+	describe('Dependencies', ({ describe }) => {
+		describe('TypeScript dependency', ({ test }) => {
+			const output = '{"default":"ts default export","namedExport":"ts named export"}';
+
+			test('Import', async () => {
+				const nodeProcess = await node.import('package-module/ts.ts');
+				expect(nodeProcess.stdout).toBe(output);
+			});
+
+			test('Import', async () => {
+				const nodeProcess = await node.import('package-typescript-export');
+				expect(nodeProcess.stdout).toBe(output);
+			});
+		});
+	});
+});

tests/fixtures/package-module/node_modules/package-typescript-export/index.ts

@@ -9,5 +9,6 @@ export default testSuite(async ({ describe }, node: NodeApis) => {
 		runTestSuite(import('./mts'), node);
 		runTestSuite(import('./cts'), node);
 		runTestSuite(import('./tsconfig'), node);
+		runTestSuite(import('./dependencies'), node);
 	});
 });