Return an error when no repository data

ui/src/lib/repositories.js

@@ -106,7 +106,7 @@ export async function getRepositories(wid, userid) {
     if (data) {
       return data.map((r) => new WorkRepository(r));
     } else {
-      return [];
+      throw new Error("No repository attached");
     }
   } else {
     throw new Error((await res.json()).errmsg);

ui/src/routes/works/[wid]/rendus.svelte

@@ -93,6 +93,8 @@
                                         </div>
                                     {/each}
                                 </div>
+                            {:catch err}
+                                -
                             {/await}
                         </td>
                         <td>