group_setting_pill: Do not allow guest users for some settings.

For settings with allow_everyone_group is False, guest users
are not allowed to do the task controlled by that setting even
if the guest user is member of the group which is used for
that setting.

So, we do not show guest users in typeahead for such settings
and also not create a pill when someone types full email of
the guest user in the input.

There is no such restriction in the API and it is fine
since we eventually have the check to not give guest user
the permission.
And we still allow guests to be part of any group, so there is
no restriction on using groups containing guests as subgroups
of the anonymous groups and showing them in typeahead.

web/src/group_setting_pill.ts

@@ -5,6 +5,7 @@ import render_input_pill from "../templates/input_pill.hbs";
 import * as group_permission_settings from "./group_permission_settings";
 import * as input_pill from "./input_pill";
 import type {InputPillConfig} from "./input_pill";
+import * as people from "./people";
 import * as pill_typeahead from "./pill_typeahead";
 import type {GroupSettingPill, GroupSettingPillContainer} from "./typeahead_helper";
 import * as user_group_pill from "./user_group_pill";
@@ -12,6 +13,7 @@ import type {UserGroupPill} from "./user_group_pill";
 import * as user_groups from "./user_groups";
 import type {UserGroup} from "./user_groups";
 import * as user_pill from "./user_pill";
+import type {UserPill} from "./user_pill";
 
 function check_group_allowed_for_setting(
     group_item: UserGroupPill,
@@ -41,17 +43,37 @@ function check_group_allowed_for_setting(
     );
 }
 
+function check_user_allowed_for_setting(
+    user_item: UserPill,
+    setting_name: string,
+    setting_type: "realm" | "stream" | "group",
+): boolean {
+    const group_setting_config = group_permission_settings.get_group_permission_setting_config(
+        setting_name,
+        setting_type,
+    );
+    assert(group_setting_config !== undefined);
+
+    if (group_setting_config.allow_everyone_group) {
+        return true;
+    }
+
+    const user = people.get_by_email(user_item.email);
+    return user !== undefined && !user.is_guest;
+}
+
 export function create_item_from_text(
     text: string,
     current_items: GroupSettingPill[],
     pill_config?: InputPillConfig,
 ): GroupSettingPill | undefined {
-    const group_item = user_group_pill.create_item_from_group_name(text, current_items);
-    if (group_item) {
     const setting_name = pill_config?.setting_name;
     assert(setting_name !== undefined);
     const setting_type = pill_config?.setting_type;
     assert(setting_type !== undefined);
+
+    const group_item = user_group_pill.create_item_from_group_name(text, current_items);
+    if (group_item) {
         if (check_group_allowed_for_setting(group_item, setting_name, setting_type)) {
             return group_item;
         }
@@ -59,7 +81,15 @@ export function create_item_from_text(
         return undefined;
     }
 
-    return user_pill.create_item_from_email(text, current_items);
+    const user_item = user_pill.create_item_from_email(text, current_items);
+    if (user_item) {
+        if (check_user_allowed_for_setting(user_item, setting_name, setting_type)) {
+            return user_item;
+        }
+        return undefined;
+    }
+
+    return undefined;
 }
 
 export function get_text_from_item(item: GroupSettingPill): string {

web/src/pill_typeahead.ts

@@ -148,7 +148,10 @@ export function set_up_group_setting_typeahead(
             let source: GroupSettingTypeaheadItem[] = [];
 
             source = user_group_pill.typeahead_source(pills, opts.setting_name, opts.setting_type);
-            source = [...source, ...user_pill.typeahead_source(pills, true)];
+            source = [
+                ...source,
+                ...user_pill.typeahead_source(pills, true, opts.setting_name, opts.setting_type),
+            ];
 
             return source;
         },

web/src/user_pill.ts

@@ -1,7 +1,10 @@
+import assert from "minimalistic-assert";
+
 import render_input_pill from "../templates/input_pill.hbs";
 
 import * as blueslip from "./blueslip";
 import type {EmojiRenderingDetails} from "./emoji";
+import * as group_permission_settings from "./group_permission_settings";
 import type {InputPillConfig, InputPillContainer} from "./input_pill";
 import * as input_pill from "./input_pill";
 import type {User} from "./people";
@@ -146,8 +149,21 @@ export function has_unconverted_data(pill_widget: UserPillWidget): boolean {
 export function typeahead_source(
     pill_widget: UserPillWidget | CombinedPillContainer | GroupSettingPillContainer,
     exclude_bots?: boolean,
+    setting_name?: string,
+    setting_type?: "realm" | "stream" | "group",
 ): UserPillData[] {
-    const users = exclude_bots ? people.get_realm_active_human_users() : people.get_realm_users();
+    let users = exclude_bots ? people.get_realm_active_human_users() : people.get_realm_users();
+    if (setting_name !== undefined) {
+        assert(setting_type !== undefined);
+        const group_setting_config = group_permission_settings.get_group_permission_setting_config(
+            setting_name,
+            setting_type,
+        );
+        assert(group_setting_config !== undefined);
+        if (!group_setting_config.allow_everyone_group) {
+            users = users.filter((user) => !user.is_guest);
+        }
+    }
     return filter_taken_users(users, pill_widget).map((user) => ({type: "user", user}));
 }