streams: Hide fake emails in stream creation form.

We hide fake emails in "People to add" section of
stream creation form and instead show user id
along with specifying that email is hidden.

frontend_tests/node_tests/people.js

@@ -151,18 +151,21 @@ const steven = {
 
 const alice1 = {
     email: "alice1@example.com",
+    delivery_email: "alice1-delivery@example.com",
     user_id: 202,
     full_name: "Alice",
 };
 
 const bob = {
     email: "bob@example.com",
+    delivery_email: "bob-delivery@example.com",
     user_id: 203,
     full_name: "Bob van Roberts",
 };
 
 const alice2 = {
     email: "alice2@example.com",
+    delivery_email: "alice2-delivery@example.com",
     user_id: 204,
     full_name: "Alice",
 };
@@ -556,15 +559,51 @@ test_people("get_people_for_stream_create", () => {
     people.add_active_user(bob);
     people.add_active_user(alice2);
     assert.equal(people.get_active_human_count(), 4);
+    page_params.is_admin = true;
+    page_params.realm_email_address_visibility = admins_only;
 
-    const others = people.get_people_for_stream_create();
+    let others = people.get_people_for_stream_create();
-    const expected = [
+    let expected = [
+        {
+            email: "alice1-delivery@example.com",
+            user_id: alice1.user_id,
+            full_name: "Alice",
+            checked: false,
+            disabled: false,
+            show_email: true,
+        },
+        {
+            email: "alice2-delivery@example.com",
+            user_id: alice2.user_id,
+            full_name: "Alice",
+            checked: false,
+            disabled: false,
+            show_email: true,
+        },
+        {
+            email: "bob-delivery@example.com",
+            user_id: bob.user_id,
+            full_name: "Bob van Roberts",
+            checked: false,
+            disabled: false,
+            show_email: true,
+        },
+    ];
+    assert.deepEqual(others, expected);
+
+    page_params.is_admin = false;
+    alice1.delivery_email = undefined;
+    alice2.delivery_email = undefined;
+    bob.delivery_email = undefined;
+    others = people.get_people_for_stream_create();
+    expected = [
         {
             email: "alice1@example.com",
             user_id: alice1.user_id,
             full_name: "Alice",
             checked: false,
             disabled: false,
+            show_email: false,
         },
         {
             email: "alice2@example.com",
@@ -572,6 +611,7 @@ test_people("get_people_for_stream_create", () => {
             full_name: "Alice",
             checked: false,
             disabled: false,
+            show_email: false,
         },
         {
             email: "bob@example.com",
@@ -579,6 +619,7 @@ test_people("get_people_for_stream_create", () => {
             full_name: "Bob van Roberts",
             checked: false,
             disabled: false,
+            show_email: false,
         },
     ];
     assert.deepEqual(others, expected);

static/js/people.js

@@ -1069,7 +1069,8 @@ export function get_people_for_stream_create() {
     for (const person of active_user_dict.values()) {
         if (!is_my_user_id(person.user_id)) {
             people_minus_you.push({
-                email: person.email,
+                email: get_visible_email(person),
+                show_email: settings_data.show_email(),
                 user_id: person.user_id,
                 full_name: person.full_name,
                 checked: false,

static/js/stream_create.js

@@ -13,6 +13,7 @@ import * as loading from "./loading";
 import {page_params} from "./page_params";
 import * as peer_data from "./peer_data";
 import * as people from "./people";
+import * as settings_data from "./settings_data";
 import * as stream_data from "./stream_data";
 import * as stream_settings_data from "./stream_settings_data";
 import * as stream_settings_ui from "./stream_settings_ui";
@@ -312,7 +313,8 @@ export function show_new_stream_modal() {
     // Add current user on top of list
     const current_user = people.get_by_user_id(page_params.user_id);
     all_users.unshift({
-        email: current_user.email,
+        show_email: settings_data.show_email(),
+        email: people.get_visible_email(current_user),
         user_id: current_user.user_id,
         full_name: current_user.full_name,
         checked: true,

static/templates/new_stream_user.hbs

@@ -1,5 +1,5 @@
 <label class="checkbox add-user-label" id="user_checkbox_{{user_id}}">
     <input type="checkbox" name="user" {{#if checked}}checked="checked"{{#if disabled}} disabled="disabled"{{/if}}{{/if}} data-user-id="{{user_id}}"/>
     <span></span>
-    {{full_name}} ({{email}})
+    {{full_name}} {{#if show_email}}({{email}}){{else}}({{#tr}}User ID: {user_id}; <em>email hidden</em>{{/tr}}){{/if}}
 </label>

tools/lib/capitalization.py

@@ -165,6 +165,8 @@ IGNORED_PHRASES = [
     # Used in our case studies
     r"Technical University of Munich",
     r"University of California San Diego",
+    # Used in stream creation form
+    r"email hidden",
 ]
 
 # Sort regexes in descending order of their lengths. As a result, the