diff --git a/src/core/collection/artist.rs b/src/core/collection/artist.rs
index 3375ade..396561b 100644
--- a/src/core/collection/artist.rs
+++ b/src/core/collection/artist.rs
@@ -526,11 +526,20 @@ mod tests {
         let mut left = FULL_COLLECTION[0].to_owned();
         let mut right = FULL_COLLECTION[1].to_owned();
         right.meta.id = left.meta.id.clone();
+
+        // The right collection needs more albums than we modify to make sure some do not overlap.
+        assert!(right.albums.len() > 2);
+
+        // This album will have a lib_id and will match based on lib_id.
         left.albums.push(right.albums[0].clone());
-        left.albums.sort_unstable();
+
+        // This album will not have a lib_id and will match based on title.
+        left.albums.push(right.albums[1].clone());
+        right.albums[1].meta.id.lib_id = AlbumLibId::None;
 
         // Albums on right without a match on the left will lose their lib id.
-        reset_lib_id(&mut right.albums[1..]);
+        let mut newly_added = right.albums[2..].to_vec();
+        reset_lib_id(&mut newly_added);
 
         let mut expected = left.clone();
         expected.meta.info.properties = expected
@@ -538,9 +547,12 @@ mod tests {
             .info
             .properties
             .merge(right.clone().meta.info.properties);
-        expected.albums.append(&mut right.albums.clone());
+        expected.albums.extend(newly_added);
         expected.albums.sort_unstable();
-        expected.albums.dedup();
+
+        // Albums are expected to be sorted.
+        left.albums.sort_unstable();
+        right.albums.sort_unstable();
 
         let merged = left.clone().merge(right);
         assert_eq!(expected, merged);