Forum previews and search results show mentions as names (GRYT-2025)

src/services/mentionSyntax.test.ts

@@ -3,7 +3,7 @@ import { readFileSync } from "node:fs";
 import { join } from "node:path";
 import { describe, it } from "node:test";
 
-import { canonicalizeMentions, mentionTarget } from "./mentionSyntax";
+import { canonicalizeMentions, mentionsAsText, mentionTarget } from "./mentionSyntax";
 
 interface Vectors {
   targets: { href: string; target: unknown }[];
@@ -54,3 +54,30 @@ describe("what the server stores", () => {
     assert.equal(out.forNicknames.includes("[@Ada](mention:user_1)"), true);
   });
 });
+
+describe("mention links as words, for previews and search (GRYT-2025)", () => {
+  const nickname = async (id: string) => ({ user_leo: "Leo", user_ada: "Ada" } as Record<string, string>)[id] ?? null;
+
+  it("names users by their current nickname, even with an empty or stale label", async () => {
+    assert.equal(await mentionsAsText("[](mention:user_leo) look at this", nickname), "@Leo look at this");
+    assert.equal(await mentionsAsText("thanks [@OldName](mention:user_ada)!", nickname), "thanks @Ada!");
+    assert.equal(await mentionsAsText("[@Gone](mention:user_gone) and [](mention:user_x)", nickname), "@Gone and @someone");
+  });
+
+  it("turns mass, role and channel links into words", async () => {
+    assert.equal(
+      await mentionsAsText("[@everyone](mention:everyone) [@here](mention:here) [@Mods](role:mods) see [#channel](channel:abc)", nickname),
+      "@everyone @here @Mods see #channel",
+    );
+  });
+
+  it("leaves code and ordinary links alone", async () => {
+    assert.equal(await mentionsAsText("`[](mention:user_leo)` and [docs](https://gryt.chat)", nickname), "`[](mention:user_leo)` and [docs](https://gryt.chat)");
+  });
+
+  it("keeps the name and drops the markup where a snippet cut through a link", async () => {
+    assert.equal(await mentionsAsText("eo](mention:user_leo) said hi", nickname), "eo said hi");
+    assert.equal(await mentionsAsText("said hi to [@Le", nickname), "said hi to [@Le");
+    assert.equal(await mentionsAsText("said hi to [@Leo](mention:user_l", nickname), "said hi to @Leo");
+  });
+});

src/services/mentionSyntax.ts

@@ -184,3 +184,40 @@ export function canonicalizeMentions(text: string, rights: MentionRights): Canon
 
   return { text: result, everyone, here, roleIds, forNicknames };
 }
+
+/* What's left where a snippet cut through a link: the end of one at the start, the start of one at the end. */
+const CUT_HEAD = /^([^[\]\n]*)\]\((?:mention|role|channel):[^)\s]*\)?/;
+const CUT_TAIL = /\[([^\]\n]*)(?:\]\((?:mention|role|channel):[^)\s]*)?$/;
+
+/**
+ * Mention, role and channel links as the words they stand for, for text shown outside a
+ * message (GRYT-2025). Users by their current nickname, since a link's label can be empty or stale.
+ */
+export async function mentionsAsText(text: string, nickname: (serverUserId: string) => Promise<string | null>): Promise<string> {
+  const names = new Map<string, string | null>();
+  for (const m of text.matchAll(LINK)) {
+    const target = mentionTarget(m[2]);
+    if (target?.kind === "user" && !names.has(target.id)) names.set(target.id, await nickname(target.id));
+  }
+  const words = (segment: string) =>
+    segment.replace(LINK, (whole: string, label: string, href: string) => {
+      const target = mentionTarget(href);
+      if (!target) return whole;
+      const bare = label.trim().replace(/^[@#]/, "");
+      if (target.kind === "user") {
+        const name = names.get(target.id) ?? bare;
+        return name ? `@${name}` : "@someone";
+      }
+      if (target.kind === "everyone" || target.kind === "here") return `@${target.kind}`;
+      if (target.kind === "role") return bare ? `@${bare}` : "@role";
+      return CHANNEL_LABEL;
+    });
+  let out = "";
+  let last = 0;
+  for (const m of text.matchAll(LITERAL)) {
+    const start = m.index ?? 0;
+    out += words(text.slice(last, start)) + m[0];
+    last = start + m[0].length;
+  }
+  return (out + words(text.slice(last))).replace(CUT_HEAD, "$1").replace(CUT_TAIL, (whole, label: string) => (whole.includes("](") ? label : whole));
+}

src/socket/handlers/chat.ts

@@ -66,7 +66,7 @@ import { applyAutoRoles } from "../../services/autoRoles";
 import { findMentions, type MentionableMember } from "../../services/mentions";
 import { pushNotify } from "../../services/push";
 import { messagePreview, previewText } from "../../services/pushPreview";
-import { canonicalizeMentions, type CanonicalMentions, type MentionRights } from "../../services/mentionSyntax";
+import { canonicalizeMentions, mentionsAsText, type CanonicalMentions, type MentionRights } from "../../services/mentionSyntax";
 import { massMentionAudience } from "../../services/massMentions";
 import { mayInChannel, mayViewChannel, visibleChannelIds } from "../../services/channelPermissions";
 import { fileReadVerdict } from "../../services/fileAccess";
@@ -131,6 +131,18 @@ async function getMentionableMembers(): Promise<MentionableMember[]> {
   return members;
 }
 
+/** Current nicknames for `mentionsAsText`, each member looked up once per request. */
+function nicknameLookup(): (serverUserId: string) => Promise<string | null> {
+  const seen = new Map<string, Promise<string | null>>();
+  return (id) => {
+    const known = seen.get(id);
+    if (known) return known;
+    const next = getUserByServerId(id).then((u) => u?.nickname ?? null, () => null);
+    seen.set(id, next);
+    return next;
+  };
+}
+
 /* The wire shape of a thread, the same one thread:created sends, so a client
    that reloads ends up with what a client that watched them arrive has. */
 function toThreadSummary(t: ThreadRecord, recentRepliers?: string[]) {
@@ -1065,11 +1077,12 @@ export function registerChatHandlers(ctx: HandlerContext): EventHandlerMap {
         const { items: hits, total } = await searchMessages({ kind, query, conversationIds, senderServerId, before, after, has, limit });
         const hidden = await blockedServerIdsFor(userId);
         const items = hidden.size === 0 ? hits : hits.filter((h) => !hidden.has(h.sender_server_id));
+        const nickname = nicknameLookup();
         socket.emit("chat:search:results", {
           requestId,
           query,
           kind,
-          items: items.map((h) => ({ ...h, created_at: h.created_at.toISOString() })),
+          items: await Promise.all(items.map(async (h) => ({ ...h, snippet: await mentionsAsText(h.snippet, nickname), created_at: h.created_at.toISOString() }))),
           total,
           hasMore: hits.length >= Math.min(Math.max(Math.floor(limit), 1), 50),
         });
@@ -1473,6 +1486,7 @@ export function registerChatHandlers(ctx: HandlerContext): EventHandlerMap {
 
         // Same base fields as chat:fetch and thread:created, plus what only a
         // topic row needs: participant count and the root's author and preview.
+        const nickname = nicknameLookup();
         const topics = await Promise.all(threads.map(async (t) => {
           const root = rootById.get(t.root_message_id);
           const participantCount = await countThreadParticipants(t.thread_id, t.root_message_id);
@@ -1482,7 +1496,7 @@ export function registerChatHandlers(ctx: HandlerContext): EventHandlerMap {
             creator_server_id: t.created_by,
             creator_nickname: root?.sender_nickname ?? null,
             creator_avatar_file_id: root?.sender_avatar_file_id ?? null,
-            preview: root?.text ? root.text.slice(0, 200) : null,
+            preview: root?.text ? (await mentionsAsText(root.text, nickname)).slice(0, 200) : null,
           };
         }));
         socket.emit("forum:topics:list", { conversation_id: payload.conversationId, topics });

src/socket/handlers/forumTopics.test.ts

@@ -122,6 +122,19 @@ describe("forum topics", () => {
     assert.ok(t.preview && t.preview.startsWith("After my laptop wakes"));
   });
 
+  it("shows a mention in the preview as the person's name, not the link (GRYT-2025)", async () => {
+    await alice.handlers["forum:topic:create"]({
+      conversationId: FORUM,
+      title: "Mentions in previews",
+      text: `[](mention:${bob.serverUserId}) can you check this?`,
+      accessToken: alice.accessToken,
+    });
+    await bob.handlers["forum:topics"]({ conversationId: FORUM });
+    const list = bob.received("forum:topics:list").at(-1) as { topics: TopicSummary[] };
+    const t = list.topics.find((x) => x.title === "Mentions in previews");
+    assert.equal(t?.preview, "@Bob can you check this?");
+  });
+
   it("counts a second person once they reply", async () => {
     await bob.handlers["chat:send"]({
       conversationId: FORUM,