fix: append trailing slash in manifest (#1507)

* fix: normalize trailing slash in prerender (#1486)

* this is a camelCase-free zone, except for public APIs

Co-authored-by: Rich Harris <[email protected]>

Author: pzerelles

packages/kit/src/core/adapt/prerender.js

@@ -90,11 +90,26 @@ export async function prerender({ cwd, out, log, config, build_data, fallback, a
 		}
 	});
 
+	/**
+	 * @param {string} path
+	 */
+	function normalize(path) {
+		if (config.kit.trailingSlash === 'always') {
+			return path.endsWith('/') ? path : `${path}/`;
+		} else if (config.kit.trailingSlash === 'never') {
+			return !path.endsWith('/') || path === '/' ? path : path.slice(0, -1);
+		}
+
+		return path;
+	}
+
 	/**
 	 * @param {string} path
 	 * @param {string} parent
 	 */
 	async function visit(path, parent) {
+		path = normalize(path);
+
 		if (seen.has(path)) return;
 		seen.add(path);