fix: add a trailing slash automatically for sourcemapBaseUrl (#5022)

fix: add a trailing slash automatically

src/utils/options/normalizeOutputOptions.ts

@@ -14,7 +14,7 @@ import {
 } from '../error';
 import { resolve } from '../path';
 import { sanitizeFileName as defaultSanitizeFileName } from '../sanitizeFileName';
-import { isValidUrl } from '../url';
+import { addTrailingSlashIfMissed, isValidUrl } from '../url';
 import {
 	URL_OUTPUT_AMD_BASEPATH,
 	URL_OUTPUT_AMD_ID,
@@ -537,7 +537,7 @@ const getSourcemapBaseUrl = (
 	const { sourcemapBaseUrl } = config;
 	if (sourcemapBaseUrl) {
 		if (isValidUrl(sourcemapBaseUrl)) {
-			return sourcemapBaseUrl;
+			return addTrailingSlashIfMissed(sourcemapBaseUrl);
 		}
 		return error(
 			errorInvalidOption(

src/utils/url.ts

@@ -10,3 +10,10 @@ export function isValidUrl(url: string): boolean {
 export function getRollupUrl(snippet: string) {
 	return `https://rollupjs.org/${snippet}`;
 }
+
+export function addTrailingSlashIfMissed(url: string) {
+	if (!url.endsWith('/')) {
+		return url + '/';
+	}
+	return url;
+}

test/sourcemaps/samples/sourcemap-base-url-without-trailing-slash/_config.js

@@ -0,0 +1,17 @@
+const assert = require('node:assert');
+
+module.exports = defineTest({
+	description: 'add a trailing slash automatically if it is missing',
+	options: {
+		output: {
+			sourcemapBaseUrl: 'https://example.com/a'
+		}
+	},
+	test: (code, map, { format }) => {
+		const sourceMappingURL = code.split('\n').slice(-2)[0];
+		assert.strictEqual(
+			sourceMappingURL,
+			`//# sourceMappingURL=https://example.com/a/bundle.${format}.js.map`
+		);
+	}
+});

test/sourcemaps/samples/sourcemap-base-url-without-trailing-slash/main.js

@@ -0,0 +1 @@
+assert.ok(true);

test/sourcemaps/samples/sourcemap-base-url/_config.js

@@ -1,22 +1,18 @@
 const assert = require('node:assert');
-const fs = require('node:fs');
-const path = require('node:path');
 
 module.exports = defineTest({
 	description: 'adds a sourcemap base url',
 	options: {
 		output: {
-			sourcemapBaseUrl: 'https://example.com'
+			sourcemapBaseUrl: 'https://example.com/a/'
 		}
 	},
-	test: (code, map, profile) => {
-		assert.equal(map.file, `bundle.${profile.format}.js`);
-		const bundlePath = path.join(__dirname, `_actual/bundle.${profile.format}.js`);
-		const bundledCode = fs.readFileSync(bundlePath, { encoding: 'utf8', flag: 'r' });
-		const sourceMappingURL = bundledCode.split('\n').slice(-2)[0];
+	test: (code, map, { format }) => {
+		assert.equal(map.file, `bundle.${format}.js`);
+		const sourceMappingURL = code.split('\n').slice(-2)[0];
 		assert.equal(
 			sourceMappingURL,
-			`//# sourceMappingURL=https://example.com/bundle.${profile.format}.js.map`
+			`//# sourceMappingURL=https://example.com/a/bundle.${format}.js.map`
 		);
 	}
 });