topics: Change topic links to use new permalinks.

This commit updates the topic links obtained from clicking
the topics in the left sidebar, recent view and inbox, and
those obtained from "Copy link to topic" to use the new
topic permalinks.

Fixes zulip#21505

web/src/echo.ts

@@ -7,9 +7,11 @@ import render_message_controls_failed_msg from "../templates/message_controls_fa
 
 import * as alert_words from "./alert_words";
 import * as blueslip from "./blueslip";
+import * as browser_history from "./browser_history";
 import * as compose_notifications from "./compose_notifications";
 import * as compose_ui from "./compose_ui";
 import * as echo_state from "./echo_state";
+import * as hash_util from "./hash_util";
 import * as local_message from "./local_message";
 import * as markdown from "./markdown";
 import * as message_events_util from "./message_events_util";
@@ -431,6 +433,28 @@ export function edit_locally(message: Message, request: LocalEditRequest): Messa
     return message;
 }
 
+export function update_topic_hash_to_contain_with_term(message: Message): void {
+    // If the current filter consists only of channel and topic terms
+    // and the incoming message belongs to same narrow, we try to
+    // update the hash, to convert to permalink.
+    if (message.type !== "stream") {
+        return;
+    }
+    const filter = message_lists.current!.data.filter;
+    if (
+        filter.is_in_channel_topic_narrow() &&
+        filter.has_operand("channel", message.stream_id.toString()) &&
+        filter.has_operand("topic", message.topic)
+    ) {
+        const narrow_terms = filter.terms();
+        const with_term = {operator: "with", operand: message.id.toString()};
+
+        narrow_terms.push(with_term);
+        const new_hash = hash_util.search_terms_to_hash(narrow_terms);
+        browser_history.set_hash(new_hash);
+    }
+}
+
 export function reify_message_id(local_id: string, server_id: number): void {
     const message = echo_state.get_message_waiting_for_id(local_id);
     echo_state.remove_message_from_waiting_for_id(local_id);
@@ -462,6 +486,7 @@ export function reify_message_id(local_id: string, server_id: number): void {
             message_id: message.id,
         });
     }
+    update_topic_hash_to_contain_with_term(message);
 }
 
 export function update_message_lists({old_id, new_id}: {old_id: number; new_id: number}): void {

web/src/filter.ts

@@ -1047,6 +1047,17 @@ export class Filter {
         return this._terms.length === 1 && this.has_operand("in", "home");
     }
 
+    is_in_channel_topic_narrow(): boolean {
+        if (
+            this.terms().length === 2 &&
+            this.has_operator("channel") &&
+            this.has_operator("topic")
+        ) {
+            return true;
+        }
+        return false;
+    }
+
     is_keyword_search(): boolean {
         return this.has_operator("search");
     }

web/src/hash_util.ts

@@ -7,6 +7,7 @@ import * as people from "./people";
 import * as settings_data from "./settings_data";
 import type {NarrowTerm} from "./state_data";
 import * as stream_data from "./stream_data";
+import {get_latest_message_id_in_topic} from "./stream_topic_history";
 import * as sub_store from "./sub_store";
 import type {StreamSubscription} from "./sub_store";
 import * as user_groups from "./user_groups";
@@ -84,6 +85,22 @@ export function by_stream_topic_url(stream_id: number, topic: string): string {
     return internal_url.by_stream_topic_url(stream_id, topic, sub_store.maybe_get_stream_name);
 }
 
+export function by_channel_topic_permalink(stream_id: number, topic: string): string {
+    const channel_topic_url = internal_url.by_stream_topic_url(
+        stream_id,
+        topic,
+        sub_store.maybe_get_stream_name,
+    );
+    const latest_msg_in_topic = get_latest_message_id_in_topic(stream_id, topic);
+
+    if (latest_msg_in_topic === undefined) {
+        return channel_topic_url;
+    }
+
+    const topic_permalink = channel_topic_url + `/with/${latest_msg_in_topic}`;
+    return topic_permalink;
+}
+
 // Encodes a term list into the
 // corresponding hash: the # component
 // of the narrow URL

web/src/inbox_ui.ts

@@ -438,7 +438,7 @@ function format_topic(
         topic_name: topic,
         unread_count: topic_unread_count,
         conversation_key: get_topic_key(stream_id, topic),
-        topic_url: hash_util.by_stream_topic_url(stream_id, topic),
+        topic_url: hash_util.by_channel_topic_permalink(stream_id, topic),
         is_hidden: filter_should_hide_stream_row({stream_id, topic}),
         is_collapsed: collapsed_containers.has(STREAM_HEADER_PREFIX + stream_id),
         mention_in_unread: unread.topic_has_any_unread_mentions(stream_id, topic),

web/src/recent_view_ui.ts

@@ -606,7 +606,7 @@ function format_conversation(conversation_data: ConversationData): ConversationC
         const is_web_public = stream_info.is_web_public;
         // Topic info
         const topic = last_msg.topic;
-        const topic_url = hash_util.by_stream_topic_url(stream_id, topic);
+        const topic_url = hash_util.by_channel_topic_permalink(stream_id, topic);
 
         // We hide the row according to filters or if it's muted.
         // We only supply the data to the topic rows and let jquery

web/src/stream_list.ts

@@ -861,7 +861,7 @@ export function set_event_handlers({
             const topic_list_info = topic_list_data.get_list_info(stream_id, false, "");
             const topic_item = topic_list_info.items[0];
             if (topic_item !== undefined) {
-                const destination_url = hash_util.by_stream_topic_url(
+                const destination_url = hash_util.by_channel_topic_permalink(
                     stream_id,
                     topic_item.topic_name,
                 );

web/src/stream_topic_history.ts

@@ -368,6 +368,14 @@ export function get_max_message_id(stream_id: number): number {
     return history.get_max_message_id();
 }
 
+export function get_latest_message_id_in_topic(
+    stream_id: number,
+    topic_name: string,
+): number | undefined {
+    const history = stream_dict.get(stream_id);
+    return history?.topics.get(topic_name)?.message_id;
+}
+
 export function reset(): void {
     // This is only used by tests.
     stream_dict.clear();

web/src/topic_popover.js

@@ -5,12 +5,12 @@ import render_delete_topic_modal from "../templates/confirm_dialog/confirm_delet
 import render_left_sidebar_topic_actions_popover from "../templates/popovers/left_sidebar/left_sidebar_topic_actions_popover.hbs";
 
 import * as confirm_dialog from "./confirm_dialog";
+import * as hash_util from "./hash_util";
 import {$t_html} from "./i18n";
 import * as message_edit from "./message_edit";
 import * as popover_menus from "./popover_menus";
 import * as popover_menus_data from "./popover_menus_data";
 import * as starred_messages_ui from "./starred_messages_ui";
-import {realm} from "./state_data";
 import * as stream_popover from "./stream_popover";
 import * as ui_util from "./ui_util";
 import * as unread_ops from "./unread_ops";
@@ -28,23 +28,22 @@ export function initialize() {
                 popover_menus.on_show_prep(instance);
                 let stream_id;
                 let topic_name;
-                let url;
 
                 if (instance.reference.classList.contains("inbox-topic-menu")) {
                     const $elt = $(instance.reference);
                     stream_id = Number.parseInt($elt.attr("data-stream-id"), 10);
                     topic_name = $elt.attr("data-topic-name");
-                    url = new URL($elt.attr("data-topic-url"), realm.realm_url);
                 } else {
                     const $elt = $(instance.reference)
                         .closest(".topic-sidebar-menu-icon")
                         .expectOne();
                     const $stream_li = $elt.closest(".narrow-filter").expectOne();
                     topic_name = $elt.closest("li").expectOne().attr("data-topic-name");
-                    url = $elt.closest("li").find(".sidebar-topic-name").expectOne().prop("href");
                     stream_id = stream_popover.elem_to_stream_id($stream_li);
                 }
 
+                const url = hash_util.by_channel_topic_permalink(stream_id, topic_name);
+
                 instance.context = popover_menus_data.get_topic_popover_content_context({
                     stream_id,
                     topic_name,

web/src/ui_init.js

@@ -658,10 +658,18 @@ export function initialize_everything(state_data) {
     topic_list.initialize({
         on_topic_click(stream_id, topic) {
             const sub = sub_store.get(stream_id);
+            const latest_msg_id = stream_topic_history.get_latest_message_id_in_topic(
+                stream_id,
+                topic,
+            );
+
+            assert(latest_msg_id !== undefined);
+
             message_view.show(
                 [
                     {operator: "channel", operand: sub.stream_id.toString()},
                     {operator: "topic", operand: topic},
+                    {operator: "with", operand: latest_msg_id},
                 ],
                 {trigger: "sidebar"},
             );

web/tests/echo.test.js

@@ -8,6 +8,7 @@ const {mock_esm, zrequire} = require("./lib/namespace");
 const {make_stub} = require("./lib/stub");
 const {run_test, noop} = require("./lib/test");
 
+const browser_history = mock_esm("../src/browser_history");
 const compose_notifications = mock_esm("../src/compose_notifications");
 const markdown = mock_esm("../src/markdown");
 const message_lists = mock_esm("../src/message_lists");
@@ -44,6 +45,13 @@ message_lists.current = {
             can_apply_locally() {
                 return true;
             },
+            is_in_channel_topic_narrow() {
+                return true;
+            },
+            has_operand() {
+                return true;
+            },
+            terms: () => [],
         },
     },
     change_message_id: noop,
@@ -68,6 +76,7 @@ message_lists.non_rendered_data = () => [];
 
 const echo = zrequire("echo");
 const echo_state = zrequire("echo_state");
+const {Filter} = zrequire("filter");
 const people = zrequire("people");
 const {set_current_user} = zrequire("state_data");
 const stream_data = zrequire("stream_data");
@@ -368,6 +377,7 @@ run_test("test reify_message_id", ({override}) => {
 
     override(markdown, "render", noop);
     override(markdown, "get_topic_links", noop);
+    override(browser_history, "set_hash", noop);
 
     const message_request = {
         type: "stream",
@@ -404,6 +414,67 @@ run_test("test reify_message_id", ({override}) => {
     assert.equal(history.topics.get("test").message_id, 110);
 });
 
+run_test("test update_topic_hash_to_contain_with_term", ({override}) => {
+    const local_id_float = 103.01;
+    let initial_hash;
+    let new_hash;
+
+    override(markdown, "render", noop);
+    override(markdown, "get_topic_links", noop);
+    override(message_store, "reify_message_id", noop);
+    override(compose_notifications, "reify_message_id", noop);
+
+    const message_request = {
+        type: "stream",
+        stream_id: general_sub.stream_id,
+        topic: "test",
+    };
+
+    // Test normal topic link converted to permalink upon arrival of a new
+    // message if it belongs to the same narrow.
+    let topic = "test";
+    initial_hash = `#narrow/stream/${general_sub.stream_id}-${general_sub.name}/topic/${topic}`;
+    new_hash = initial_hash;
+
+    override(browser_history, "set_hash", (updated_hash) => {
+        new_hash = updated_hash;
+    });
+
+    message_lists.current.data.filter = new Filter([
+        {operator: "channel", operand: general_sub.stream_id.toString()},
+        {operator: "topic", operand: topic},
+    ]);
+
+    echo.insert_local_message(message_request, local_id_float, (messages) => {
+        messages.map((message) => echo.track_local_message(message));
+        return messages;
+    });
+    echo.reify_message_id(local_id_float.toString(), 110);
+
+    assert.equal(
+        new_hash,
+        `#narrow/stream/${general_sub.stream_id}-${general_sub.name}/topic/${topic}/with/110`,
+    );
+
+    // No change in current hash if incoming message is of different
+    // narrow.
+    topic = "testing";
+    initial_hash = `#narrow/stream/${general_sub.stream_id}-${general_sub.name}/topic/${topic}`;
+    new_hash = initial_hash;
+
+    message_lists.current.data.filter = new Filter([
+        {operator: "channel", operand: general_sub.stream_id.toString()},
+        {operator: "topic", operand: topic},
+    ]);
+
+    echo.insert_local_message(message_request, local_id_float, (messages) => {
+        messages.map((message) => echo.track_local_message(message));
+        return messages;
+    });
+    echo.reify_message_id(local_id_float.toString(), 110);
+    assert.equal(new_hash, initial_hash);
+});
+
 run_test("reset MockDate", () => {
     MockDate.reset();
 });

web/tests/filter.test.js

@@ -338,6 +338,7 @@ test("basics", () => {
     assert.ok(!filter.is_personal_filter());
     assert.ok(filter.is_conversation_view());
     assert.ok(!filter.is_conversation_view_with_near());
+    assert.ok(!filter.is_in_channel_topic_narrow());
 
     terms = [
         {operator: "dm", operand: "[email protected]"},
@@ -364,6 +365,7 @@ test("basics", () => {
     assert.ok(!filter.is_personal_filter());
     assert.ok(filter.is_conversation_view());
     assert.ok(!filter.is_conversation_view_with_near());
+    assert.ok(!filter.is_in_channel_topic_narrow());
 
     terms = [
         {operator: "dm", operand: "[email protected],[email protected]"},
@@ -450,6 +452,7 @@ test("basics", () => {
     assert.ok(!filter.is_personal_filter());
     assert.ok(filter.is_conversation_view());
     assert.ok(!filter.is_conversation_view_with_near());
+    assert.ok(filter.is_in_channel_topic_narrow());
 
     terms = [
         {operator: "channel", operand: foo_stream_id.toString()},

web/tests/recent_view.test.js

@@ -9,6 +9,7 @@ const {page_params} = require("./lib/zpage_params");
 
 window.scrollTo = noop;
 const test_url = () => "https://www.example.com";
+const test_permalink = () => "https://www.example.com/with/12";
 
 // We assign this in our test() wrapper.
 let messages;
@@ -94,6 +95,7 @@ mock_esm("../src/compose_closed_ui", {
 mock_esm("../src/hash_util", {
     by_stream_url: test_url,
     by_stream_topic_url: test_url,
+    by_channel_topic_permalink: test_permalink,
     by_conversation_and_time_url: test_url,
 });
 mock_esm("../src/message_list_data", {
@@ -410,7 +412,7 @@ function generate_topic_data(topic_info_array) {
             stream_url: "https://www.example.com",
             topic,
             conversation_key: get_topic_key(stream_id, topic),
-            topic_url: "https://www.example.com",
+            topic_url: "https://www.example.com/with/12",
             unread_count,
             mention_in_unread: false,
             visibility_policy,

web/tests/stream_topic_history.test.js

@@ -355,6 +355,14 @@ test("server_history_end_to_end", () => {
     const history = stream_topic_history.get_recent_topic_names(stream_id);
     assert.deepEqual(history, ["topic3", "topic2", "topic1"]);
 
+    for (const topic of topics) {
+        const last_msg_id_in_topic = stream_topic_history.get_latest_message_id_in_topic(
+            stream_id,
+            topic.name,
+        );
+        assert.deepEqual(last_msg_id_in_topic, topic.max_id);
+    }
+
     // Try getting server history for a second time.
 
     /* istanbul ignore next */