Was trying to 'catch out' the mutation handling by having siblings present on mutation processing before they could be added, but couldn't (deliberately) break anything. Adding test anyway as it might throw up an interesting scenario

eoghanmurray · eoghanmurray · commit 4c2af793aab4 · 2025-03-07T12:49:04.000Z
diff --git a/packages/rrweb/test/html/mutation.html b/packages/rrweb/test/html/mutation.html
@@ -1,5 +1,4 @@
 <!DOCTYPE html>
 <html>
-  <body>
-  </body>
+  <body></body>
 </html>
diff --git a/packages/rrweb/test/record/__snapshots__/mutation.test.ts.mutation.siblings_added_in_idleCallback.snap.json b/packages/rrweb/test/record/__snapshots__/mutation.test.ts.mutation.siblings_added_in_idleCallback.snap.json
@@ -0,0 +1,62 @@
+[
+  {
+    "type": 3,
+    "data": {
+      "source": 0,
+      "texts": [],
+      "attributes": [],
+      "removes": [
+        {
+          "parentId": 7,
+          "id": 8
+        }
+      ],
+      "adds": [
+        {
+          "parentId": 7,
+          "nextId": null,
+          "node": {
+            "type": 2,
+            "tagName": "div",
+            "attributes": {},
+            "childNodes": [],
+            "id": 9
+          }
+        }
+      ]
+    }
+  },
+  {
+    "type": 3,
+    "data": {
+      "source": 0,
+      "texts": [],
+      "attributes": [],
+      "removes": [],
+      "adds": [
+        {
+          "parentId": 7,
+          "nextId": null,
+          "node": {
+            "type": 2,
+            "tagName": "div",
+            "attributes": {},
+            "childNodes": [],
+            "id": 10
+          }
+        },
+        {
+          "parentId": 7,
+          "nextId": 9,
+          "node": {
+            "type": 2,
+            "tagName": "div",
+            "attributes": {},
+            "childNodes": [],
+            "id": 11
+          }
+        }
+      ]
+    }
+  }
+]
diff --git a/packages/rrweb/test/record/mutation.test.ts b/packages/rrweb/test/record/mutation.test.ts
@@ -262,4 +262,21 @@ describe('mutation', () => {
     const mutations = events.filter((e)=>e.type === EventType.IncrementalSnapshot);
     await assertSnapshot(mutations, true);
   });
+
+  it('siblings added in idleCallback', async () => {
+    await page.evaluate(() => {
+      document.body.childNodes.forEach((cn) => document.body.removeChild(cn)); // clear out text nodes created by server
+      document.body.prepend(document.createElement('div'));
+      requestAnimationFrame(() => {
+        //rrweb.freezePage();
+        document.body.prepend(document.createElement('div'));
+        document.body.append(document.createElement('div'));
+      });
+    });
+    await waitForRAF(page);
+    const mutations = events.filter(
+      (e) => e.type === EventType.IncrementalSnapshot,
+    );
+    await assertSnapshot(mutations, true);
+  });
 });

-Original file line number
+Diff line change
@@ @@ -1,5 +1,4 @@ @@
 <!DOCTYPE html>
 <html>
 -  <body>
 -  </body>
 +  <body></body>
 </html>