add displayname to parent posts

public/src/modules/helpers.common.js

@@ -327,11 +327,11 @@ module.exports = function (utils, Benchpress, relative_path) {
 	}
 
 	function generateRepliedTo(post, timeagoCutoff) {
-		const username = post.parent && post.parent.username ?
-			post.parent.username : '[[global:guest]]';
+		const displayname = post.parent && post.parent.displayname ?
+			post.parent.displayname : '[[global:guest]]';
 		const isBeforeCutoff = post.timestamp < (Date.now() - (timeagoCutoff * oneDayInMs));
 		const langSuffix = isBeforeCutoff ? 'on' : 'ago';
-		return `[[topic:replied-to-user-${langSuffix}, ${post.toPid}, ${relative_path}/post/${post.toPid}, ${username}, ${relative_path}/post/${post.pid}, ${post.timestampISO}]]`;
+		return `[[topic:replied-to-user-${langSuffix}, ${post.toPid}, ${relative_path}/post/${post.toPid}, ${displayname}, ${relative_path}/post/${post.pid}, ${post.timestampISO}]]`;
 	}
 
 	function generateWrote(post, timeagoCutoff) {

src/topics/posts.js

@@ -186,13 +186,13 @@ module.exports = function (Topics) {
 		const parentUids = _.uniq(parentPosts.map(postObj => postObj && postObj.uid));
 		const userData = await user.getUsersFields(parentUids, ['username']);
 
-		const usersMap = {};
-		userData.forEach((user) => {
-			usersMap[user.uid] = user.username;
-		});
+		const usersMap = _.zipObject(parentUids, userData);
 		const parents = {};
 		parentPosts.forEach((post, i) => {
-			parents[parentPids[i]] = { username: usersMap[post.uid] };
+			parents[parentPids[i]] = {
+				username: usersMap[post.uid].username,
+				displayname: usersMap[post.uid].displayname,
+			};
 		});
 
 		postData.forEach((post) => {