diff --git a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.html b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.html
index 24afe87..7117574 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.html
@@ -777,7 +777,17 @@
       const commentSide = 'left';
 
       assert.isOk(element._getOrCreateThread(threadGroupEl,
-          commentSide));
+          commentSide, undefined, false, '2'));
+
+      let threads = Polymer.dom(threadGroupEl)
+          .queryDistributedElements('gr-diff-comment-thread');
+
+      assert.equal(threads.length, 1);
+      assert.equal(threads[0].commentSide, commentSide);
+      assert.equal(threads[0].range, undefined);
+      assert.equal(threads[0].isOnParent, false);
+      assert.equal(threads[0].patchNum, 2);
+
 
       // Try to fetch a thread with a different range.
       range = {
@@ -788,10 +798,16 @@
       };
 
       assert.isOk(element._getOrCreateThread(
-          threadGroupEl, commentSide, range));
-      const threadCount = Polymer.dom(threadGroupEl.root).
-            querySelectorAll('gr-diff-comment-thread').length;
-      assert.equal(threadCount, 2);
+          threadGroupEl, commentSide, range, true, '3'));
+
+      threads = Polymer.dom(threadGroupEl)
+          .queryDistributedElements('gr-diff-comment-thread');
+
+      assert.equal(threads.length, 2);
+      assert.equal(threads[1].commentSide, commentSide);
+      assert.equal(threads[1].range, range);
+      assert.equal(threads[1].isOnParent, true);
+      assert.equal(threads[1].patchNum, 3);
     });
 
     suite('_translateChunksToIgnore', () => {