stream_settings: Add new topics_policy setting.

Added `topics_policy` channel setting to configure sending
messages in the empty topic.

Fixes #33549.

web/tests/compose.test.cjs

@@ -126,6 +126,7 @@ const social = {
     name: "social",
     subscribed: true,
     can_send_message_group: 2,
+    topics_policy: "inherit",
 };
 stream_data.add_sub(social);
 

web/tests/compose_fade.test.cjs

@@ -12,15 +12,6 @@ mock_jquery((selector) => {
                 val() {
                     return "lunch";
                 },
-                is(arg) {
-                    switch (arg) {
-                        case ":focus":
-                            return true;
-                        /* istanbul ignore next */
-                        default:
-                            throw new Error(`Unknown arg ${arg}`);
-                    }
-                },
             };
         /* istanbul ignore next */
         default:

web/tests/compose_ui.test.cjs

@@ -1296,6 +1296,14 @@ run_test("get_focus_area", ({override}) => {
         get_focus_area({message_type: "stream"}),
         "#compose_select_recipient_widget_wrapper",
     );
+
+    stream_data.add_sub({
+        message_type: "stream",
+        name: "fun",
+        stream_id: 4,
+        topics_policy: "inherit",
+    });
+
     override(realm, "realm_topics_policy", "disable_empty_topic");
     assert.equal(
         get_focus_area({message_type: "stream", stream_name: "fun", stream_id: 4}),

web/tests/compose_validate.test.cjs

@@ -347,7 +347,6 @@ test_ui("validate", ({mock_template, override}) => {
     let missing_topic_error_rendered = false;
     mock_template("compose_banner/compose_banner.hbs", false, (data) => {
         assert.equal(data.classname, compose_banner.CLASSNAMES.topic_missing);
-        assert.equal(data.banner_text, compose_validate.TOPICS_REQUIRED_ERROR_MESSAGE);
         missing_topic_error_rendered = true;
         return "<banner-stub>";
     });
@@ -412,6 +411,7 @@ test_ui("validate_stream_message", ({override, override_rewire, mock_template})
         name: "special",
         subscribed: true,
         can_send_message_group: everyone.id,
+        topics_policy: "inherit",
     };
     stream_data.add_sub(special_sub);
 

web/tests/lib/events.cjs

@@ -54,6 +54,7 @@ exports.test_streams = {
         is_web_public: false,
         message_retention_days: null,
         stream_post_policy: 1,
+        topics_policy: "inherit",
         can_administer_channel_group: 2,
         can_send_message_group: 2,
         can_remove_subscribers_group: 2,
@@ -74,6 +75,7 @@ exports.test_streams = {
         is_announcement_only: false,
         message_retention_days: null,
         stream_post_policy: 1,
+        topics_policy: "inherit",
         can_administer_channel_group: 2,
         can_send_message_group: 2,
         can_remove_subscribers_group: 2,

web/tests/message_view.test.cjs

@@ -800,7 +800,7 @@ run_test("narrow_to_compose_target streams", ({override, override_rewire}) => {
 
     compose_state.set_message_type("stream");
     const rome_id = 99;
-    stream_data.add_sub({name: "ROME", stream_id: rome_id});
+    stream_data.add_sub({name: "ROME", stream_id: rome_id, topics_policy: "inherit"});
     compose_state.set_stream_id(99);
 
     // Test with existing topic

web/tests/settings_data.test.cjs

@@ -205,11 +205,6 @@ test_realm_group_settings(
     settings_data.can_subscribe_others_to_all_accessible_streams,
 );
 
-test_realm_group_settings(
-    "realm_can_set_topics_policy_group",
-    settings_data.user_can_set_topics_policy,
-);
-
 test_realm_group_settings(
     "realm_can_delete_any_message_group",
     settings_data.user_can_delete_any_message,

web/tests/stream_data.test.cjs

@@ -829,6 +829,7 @@ test("stream_settings", ({override}) => {
         history_public_to_subscribers: false,
     });
     stream_data.update_message_retention_setting(sub, -1);
+    stream_data.update_topics_policy_setting(sub, "allow_topics_policy");
     stream_data.update_stream_permission_group_setting(
         "can_remove_subscribers_group",
         sub,
@@ -843,6 +844,7 @@ test("stream_settings", ({override}) => {
     assert.equal(sub.invite_only, false);
     assert.equal(sub.history_public_to_subscribers, false);
     assert.equal(sub.message_retention_days, -1);
+    assert.equal(sub.topics_policy, "allow_topics_policy");
     assert.equal(sub.can_remove_subscribers_group, moderators_group.id);
     assert.equal(sub.can_administer_channel_group, moderators_group.id);
     assert.equal(sub.folder_id, 3);
@@ -1649,6 +1651,41 @@ test("can_subscribe_others", ({override}) => {
     assert.equal(stream_data.can_subscribe_others(sub), false);
 });
 
+test("user_can_set_topics_policy", ({override}) => {
+    const sub = {
+        name: "Denmark",
+        subscribed: true,
+        color: "red",
+        stream_id: 1,
+        can_add_subscribers_group: admins_group.id,
+        can_administer_channel_group: nobody_group.id,
+        can_remove_subscribers_group: admins_group.id,
+    };
+    stream_data.add_sub(sub);
+
+    override(realm, "realm_can_set_topics_policy_group", nobody_group.id);
+    // Admins can always change per-channel topics policy.
+    initialize_and_override_current_user(admin_user_id, override);
+    override(current_user, "is_admin", true);
+    assert.equal(stream_data.user_can_set_topics_policy(sub), true);
+
+    initialize_and_override_current_user(moderator_user_id, override);
+    override(current_user, "is_admin", false);
+    assert.equal(stream_data.user_can_set_topics_policy(sub), false);
+
+    // Not allowed as user not in can_administer_channel_group.
+    override(realm, "realm_can_set_topics_policy_group", everyone_group.id);
+    assert.equal(stream_data.user_can_set_topics_policy(sub), false);
+
+    sub.can_administer_channel_group = moderators_group.id;
+    assert.equal(stream_data.user_can_set_topics_policy(sub), true);
+
+    // Only realm_can_set_topics_policy_group is checked if sub is not provided.
+    assert.equal(stream_data.user_can_set_topics_policy(), true);
+    override(realm, "realm_can_set_topics_policy_group", nobody_group.id);
+    assert.equal(stream_data.user_can_set_topics_policy(sub), false);
+});
+
 test("options for dropdown widget", () => {
     const denmark = {
         subscribed: true,

web/tests/stream_events.test.cjs

@@ -278,6 +278,19 @@ test("update_property", ({override}) => {
         assert.equal(args.val, 20);
     }
 
+    // Test stream topics_policy change event
+    {
+        const stub = make_stub();
+        override(stream_settings_ui, "update_topics_policy_setting", stub.f);
+        override(compose_recipient, "update_topic_inputbox_on_topics_policy_change", noop);
+        override(compose_recipient, "update_compose_area_placeholder_text", noop);
+        stream_events.update_property(stream_id, "topics_policy", "allow_topics_policy");
+        assert.equal(stub.num_calls, 1);
+        const args = stub.get_args("sub", "val");
+        assert.equal(args.sub.stream_id, stream_id);
+        assert.equal(args.val, "allow_topics_policy");
+    }
+
     // Test stream can_remove_subscribers_group change event
     {
         const stub = make_stub();