Change detailed status child ordering to sort self-replies on top (mastodon#11686)

Fixes mastodon#11679

Author: ClearlyClaire

app/javascript/mastodon/features/status/index.js

@@ -84,28 +84,38 @@ const makeMapStateToProps = () => {
   const getDescendantsIds = createSelector([
     (_, { id }) => id,
     state => state.getIn(['contexts', 'replies']),
-  ], (statusId, contextReplies) => {
-    let descendantsIds = Immutable.List();
-    descendantsIds = descendantsIds.withMutations(mutable => {
-      const ids = [statusId];
+    state => state.get('statuses'),
+  ], (statusId, contextReplies, statuses) => {
+    let descendantsIds = [];
+    const ids = [statusId];
 
-      while (ids.length > 0) {
-        let id        = ids.shift();
-        const replies = contextReplies.get(id);
+    while (ids.length > 0) {
+      let id        = ids.shift();
+      const replies = contextReplies.get(id);
 
-        if (statusId !== id) {
-          mutable.push(id);
-        }
+      if (statusId !== id) {
+        descendantsIds.push(id);
+      }
 
-        if (replies) {
-          replies.reverse().forEach(reply => {
-            ids.unshift(reply);
-          });
-        }
+      if (replies) {
+        replies.reverse().forEach(reply => {
+          ids.unshift(reply);
+        });
       }
-    });
+    }
+
+    let insertAt = descendantsIds.findIndex((id) => statuses.get(id).get('in_reply_to_account_id') !== statuses.get(id).get('account'));
+    if (insertAt !== -1) {
+      descendantsIds.forEach((id, idx) => {
+        if (idx > insertAt && statuses.get(id).get('in_reply_to_account_id') === statuses.get(id).get('account')) {
+          descendantsIds.splice(idx, 1);
+          descendantsIds.splice(insertAt, 0, id);
+          insertAt += 1;
+        }
+      });
+    }
 
-    return descendantsIds;
+    return Immutable.List(descendantsIds);
   });
 
   const mapStateToProps = (state, props) => {