src/shared/lib/utils/buildQueryString/buildQueryString.ts

@@ -7,7 +7,7 @@
  * @example
  * ```ts
  * buildQueryString({ category: 'serif', subsets: ['latin', 'latin-ext'] })
- * // Returns: "?category=serif&subsets=latin%2Clatin-ext"
+ * // Returns: "?category=serif&subsets=latin&subsets=latin-ext"
  *
  * buildQueryString({ limit: 50, page: 1 })
  * // Returns: "?limit=50&page=1"
@@ -16,7 +16,7 @@
  * // Returns: ""
  *
  * buildQueryString({ search: 'hello world', active: true })
- * // Returns: "?search=hello%20world&active=true"
+ * // Returns: "?search=hello+world&active=true"
  * ```
  */
 
@@ -35,7 +35,7 @@ export type QueryParams = Record<string, QueryParamValue | undefined | null>;
  *
  * Handles:
  * - Primitive values (string, number, boolean) - converted to strings
- * - Arrays - comma-separated values
+ * - Arrays - multiple parameters with same key (e.g., ?key=1&key=2&key=3)
  * - null/undefined - omitted from output
  * - Special characters - URL encoded
  *
@@ -51,14 +51,12 @@ export function buildQueryString(params: QueryParams): string {
             continue;
         }
 
-        // Handle arrays (comma-separated values)
+        // Handle arrays - append each item as separate parameter with same key
         if (Array.isArray(value)) {
-            const joined = value
+            for (const item of value) {
-                .filter(item => item !== undefined && item !== null)
+                if (item !== undefined && item !== null) {
-                .map(String)
+                    searchParams.append(key, String(item));
-                .join(',');
+                }
-            if (joined) {
-                searchParams.append(key, joined);
             }
         } else {
             // Handle primitives