fix(storage_client): prevent the SDK from throwing when null path was returned from calling createSignedUrls() (supabase#599)

* fix: add test case for createSignedUrls

* format document

* log returned value

* upload file in test before getting signed urls

* log response

* pass a fall back empty string for path

* update comments

Author: dshukertjr

packages/storage_client/lib/src/storage_file_api.dart

@@ -363,7 +363,9 @@ class StorageFileApi {
     );
     final List<SignedUrl> urls = (response as List).map((e) {
       return SignedUrl(
-        path: e['path'],
+        // Prevents exceptions being thrown when null value is returned
+        // https://github.com/supabase/storage-api/issues/353
+        path: e['path'] ?? '',
         signedUrl: '$url${e['signedURL']}',
       );
     }).toList();

packages/storage_client/test/client_test.dart

@@ -71,6 +71,10 @@ void main() {
     final response = await storage.createBucket(newBucketName);
     expect(response, newBucketName);
   });
+  test('createSignedUrls does not throw', () async {
+    await storage.from(newBucketName).upload(uploadPath, file);
+    await storage.from(newBucketName).createSignedUrls([uploadPath], 2000);
+  });
 
   test('Create new public bucket', () async {
     const newPublicBucketName = 'my-new-public-bucket';