fix: normalizePathSlashes should normalize multiple leading slashes

src/routes.ts

@@ -86,7 +86,7 @@ export function createHref(
 
     const compiledRoute = `${compile(preparedRoute)(params)}${search}`;
 
-    if (options.withBasename) {
+    if (options.withBasename && basename) {
         // For SPA links react-router adds basename itself
         // It is needed for external links - <a> or uikit <Link>
         return normalizePathSlashes(`${basename}/${compiledRoute}`);

src/utils/__test__/index.test.ts

@@ -16,6 +16,9 @@ describe('normalizePathSlashes', () => {
     test('should handle paths with multiple trailing slashes', () => {
         expect(normalizePathSlashes('path////')).toBe('path/');
     });
+    test('should handle paths with multiple leading slashes', () => {
+        expect(normalizePathSlashes('////path')).toBe('/path');
+    });
     test('should handle full paths with normal slashes', () => {
         expect(normalizePathSlashes('http://example.com/path/to/resource')).toBe(
             'http://example.com/path/to/resource',
@@ -26,9 +29,14 @@ describe('normalizePathSlashes', () => {
             'http://example.com/path/to/resource',
         );
     });
+    test('should not replace double slashes near protocols (after a colon)', () => {
+        expect(normalizePathSlashes('http://host.ydb.com')).toBe('http://host.ydb.com');
+        expect(normalizePathSlashes('https://host.ydb.com')).toBe('https://host.ydb.com');
+        expect(normalizePathSlashes('grpc://host.ydb.com')).toBe('grpc://host.ydb.com');
+    });
     test('should replace slashes more than two slashes after a colon', () => {
-        expect(normalizePathSlashes('http://///example.com/path/to/resource')).toBe(
-            'http://example.com/path/to/resource',
-        );
+        expect(normalizePathSlashes('http:////host.ydb.com')).toBe('http://host.ydb.com');
+        expect(normalizePathSlashes('https://///host.ydb.com')).toBe('https://host.ydb.com');
+        expect(normalizePathSlashes('grpc://///host.ydb.com')).toBe('grpc://host.ydb.com');
     });
 });

src/utils/index.ts

@@ -14,5 +14,6 @@ export async function wait<T = unknown>(time: number, value?: T): Promise<T | un
 
 export function normalizePathSlashes(path: string) {
     // Prevent multiple slashes when concatenating path parts
-    return path.replaceAll(/([^:])(\/\/+)/g, '$1/');
+    // (?<!:) - negative lookbehind - ignore parts that start with :
+    return path.replaceAll(/(?<!:)\/\/+/g, '/');
 }