fixed appending

src/music_kraken/objects/collection.py

@@ -42,6 +42,9 @@ class Collection:
 
     def map_element(self, element: DatabaseObject):
         for name, value in element.indexing_values:
+            if value is None:
+                continue
+
             self._attribute_to_object_map[name][value] = element
 
     def append(self, element: DatabaseObject, merge_on_conflict: bool = True):
@@ -57,12 +60,13 @@ class Collection:
 
         for name, value in element.indexing_values:
             if value in self._attribute_to_object_map[name]:
-                # if the object does already exist
-                # thus merging and don't add it afterwards
-                existing_object = self._attribute_to_object_map[name][value]
-                existing_object.merge(element)
-                # in case any relevant data has been added (e.g. it remaps the old object)
-                self.map_element(existing_object)
+                if merge_on_conflict:
+                    # if the object does already exist
+                    # thus merging and don't add it afterwards
+                    existing_object = self._attribute_to_object_map[name][value]
+                    existing_object.merge(element)
+                    # in case any relevant data has been added (e.g. it remaps the old object)
+                    self.map_element(existing_object)
                 return
 
         self._data.append(element)

src/music_kraken/objects/parents.py

@@ -56,12 +56,12 @@ class DatabaseObject:
         return list()
         
     def merge(self, other, override: bool = False):
-        if isinstance(other, type(self)):
+        if not isinstance(other, type(self)):
             LOGGER.warning(f"can't merge \"{type(other)}\" into \"{type(self)}\"")
             return
 
         for collection in type(self).COLLECTION_ATTRIBUTES:
-            getattr(self, collection).extend(collection)
+            getattr(self, collection).extend(getattr(other, collection))
 
         for simple_attribute in type(self).SIMPLE_ATTRIBUTES:
             if getattr(other, simple_attribute) is None:

src/music_kraken/objects/song.py

@@ -87,7 +87,7 @@ class Song(MainObject):
         return [
             ('id', self.id),
             ('title', self.unified_title),
-            ('isrc', self.isrc.strip()),
+            ('isrc', self.isrc),
             *[('url', source.url) for source in self.source_collection]
         ]