eslint: Enable arrow-body-style.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

.eslintrc.json

@@ -17,6 +17,7 @@
     "rules": {
         "array-callback-return": "error",
         "array-bracket-spacing": "error",
+        "arrow-body-style": "error",
         "arrow-parens": "error",
         "arrow-spacing": [ "error", { "before": true, "after": true } ],
         "block-scoped-var": "error",

frontend_tests/node_tests/billing.js

@@ -62,9 +62,7 @@ run_test("initialize", () => {
         };
     };
 
-    $("#payment-method").data = (key) => {
+    $("#payment-method").data = (key) => document.querySelector("#payment-method").getAttribute("data-" + key);
-        return document.querySelector("#payment-method").getAttribute("data-" + key);
-    };
 
     jquery_init();
 

frontend_tests/node_tests/billing_helpers.js

@@ -102,9 +102,7 @@ run_test('create_ajax_request', () => {
     };
 
 
-    $("#autopay-form").serializeArray = () => {
+    $("#autopay-form").serializeArray = () => jquery("#autopay-form").serializeArray();
-        return jquery("#autopay-form").serializeArray();
-    };
 
     $.post = ({url, data, success, error}) => {
         assert.equal(state.form_input_section_hide, 1);

frontend_tests/node_tests/buddy_list.js

@@ -183,9 +183,7 @@ run_test('find_li w/force_render', () => {
     assert.equal(li, stub_li);
     assert(shown);
 
-    buddy_list.get_li_from_key = () => {
+    buddy_list.get_li_from_key = () => ({length: 0});
-        return {length: 0};
-    };
 
     const undefined_li = buddy_list.find_li({
         key: 'not-there',

frontend_tests/node_tests/compose.js

@@ -1706,7 +1706,7 @@ run_test('nonexistent_stream_reply_error', () => {
 });
 
 run_test('narrow_button_titles', () => {
-    util.is_mobile = () => { return false; };
+    util.is_mobile = () => false;
 
     compose.update_closed_compose_buttons_for_private();
     assert.equal($("#left_bar_compose_stream_button_big").text(), i18n.t("New stream message"));

frontend_tests/node_tests/dropdown_list_widget.js

@@ -4,9 +4,7 @@ set_global('$', global.make_zjquery());
 
 const noop = () => {};
 const _list_render = {
-    create: () => {
+    create: () => ({ init: noop }),
-        return { init: noop };
-    },
 };
 set_global('list_render', _list_render);
 

frontend_tests/node_tests/hashchange.js

@@ -152,9 +152,7 @@ function test_helper() {
         assert_events: (expected_events) => {
             assert.deepEqual(expected_events, events);
         },
-        get_narrow_terms: () => {
+        get_narrow_terms: () => narrow_terms,
-            return narrow_terms;
-        },
     };
 }
 

frontend_tests/node_tests/input_pill.js

@@ -13,11 +13,9 @@ set_global('ui_util', {
     place_caret_at_end: noop,
 });
 
-set_global('getSelection', () => {
+set_global('getSelection', () => ({
-    return {
     anchorOffset: 0,
-    };
+}));
-});
 
 let id_seq = 0;
 run_test('set_up_ids', () => {
@@ -240,20 +238,16 @@ run_test('arrows on pills', () => {
     let next_focused = false;
 
     const pill_stub = {
-        prev: () => {
+        prev: () => ({
-            return {
             focus: () => {
                 prev_focused = true;
             },
-            };
+        }),
-        },
+        next: () => ({
-        next: () => {
-            return {
             focus: () => {
                 next_focused = true;
             },
-            };
+        }),
-        },
     };
 
     container.set_find_results('.pill:focus', pill_stub);
@@ -282,13 +276,11 @@ run_test('left arrow on input', () => {
     let last_pill_focused = false;
 
     container.set_find_results('.pill', {
-        last: () => {
+        last: () => ({
-            return {
             focus: () => {
                 last_pill_focused = true;
             },
-            };
+        }),
-        },
     });
 
     key_handler({
@@ -498,14 +490,12 @@ run_test('exit button on pill', () => {
     };
 
     const exit_button_stub = {
-        to_$: () => {
+        to_$: () => ({
-            return {
             closest: (sel) => {
                 assert.equal(sel, '.pill');
                 return curr_pill_stub;
             },
-            };
+        }),
-        },
     };
 
     const e = {
@@ -538,14 +528,12 @@ run_test('misc things', () => {
     let shake_class_removed = false;
 
     const input_stub = {
-        to_$: () => {
+        to_$: () => ({
-            return {
             removeClass: (cls) => {
                 assert.equal(cls, 'shake');
                 shake_class_removed = true;
             },
-            };
+        }),
-        },
     };
 
     animation_end_handler.call(input_stub);

frontend_tests/node_tests/list_cursor.js

@@ -59,9 +59,7 @@ run_test('single item list', () => {
 
     cursor.adjust_scroll = () => {};
 
-    conf.list.find_li = () => {
+    conf.list.find_li = () => li_stub;
-        return li_stub;
-    };
 
     cursor.go_to(valid_key);
 

frontend_tests/node_tests/list_render.js

@@ -198,9 +198,7 @@ run_test('filtering', () => {
     const opts = {
         filter: {
             element: search_input,
-            predicate: (item, value) => {
+            predicate: (item, value) => item.includes(value),
-                return item.includes(value);
-            },
         },
         modifier: (item) => div(item),
     };
@@ -294,9 +292,7 @@ function sort_button(opts) {
         addClass: (cls) => {
             classList.add(cls);
         },
-        hasClass: (cls) => {
+        hasClass: (cls) => classList.has(cls),
-            return classList.has(cls);
-        },
         removeClass: (cls) => {
             classList.delete(cls);
         },
@@ -332,11 +328,7 @@ run_test('wire up filter element', () => {
 
     const opts = {
         filter: {
-            filterer: (list, value) => {
+            filterer: (list, value) => list.filter((item) => item.toLowerCase().includes(value)),
-                return list.filter((item) => {
-                    return item.toLowerCase().includes(value);
-                });
-            },
             element: filter_element,
         },
         modifier: (s) => '(' + s + ')',
@@ -372,9 +364,7 @@ run_test('sorting', () => {
     const opts = {
         name: 'sorting-list',
         parent_container: sort_container,
-        modifier: (item) => {
+        modifier: (item) => div(item.name) + div(item.salary),
-            return div(item.name) + div(item.salary);
-        },
         filter: {
             predicate: () => true,
         },
@@ -698,9 +688,7 @@ run_test('opts.get_item', () => {
         ['one', 'two', 'three', 'four']
     );
 
-    const predicate = (item, value) => {
+    const predicate = (item, value) => item.startsWith(value);
-        return item.startsWith(value);
-    };
 
     const predicate_opts = {
         get_item: (n) => items[n],
@@ -719,11 +707,7 @@ run_test('opts.get_item', () => {
     const filterer_opts = {
         get_item: (n) => items[n],
         filter: {
-            filterer: (items, value) => {
+            filterer: (items, value) => items.filter((item) => predicate(item, value)),
-                return items.filter((item) => {
-                    return predicate(item, value);
-                });
-            },
         },
     };
 
@@ -821,9 +805,7 @@ run_test('render item', () => {
     let rendering_item = false;
     const widget_3 = list_render.create(container, list, {
         name: 'replace-list',
-        modifier: (item) => {
+        modifier: (item) => rendering_item ? undefined : `${item}\n`,
-            return rendering_item ? undefined : `${item}\n`;
-        },
         get_item: get_item,
         html_selector: (item) => `tr[data-item='${item}']`,
     });

frontend_tests/node_tests/message_list.js

@@ -18,9 +18,7 @@ const with_overrides = global.with_overrides; // make lint happy
 
 function accept_all_filter() {
     const filter = {
-        predicate: () => {
+        predicate: () => () => true,
-            return () => true;
-        },
     };
 
     return filter;

frontend_tests/node_tests/narrow_activate.js

@@ -150,16 +150,14 @@ run_test('basics', () => {
 
     const row = {
         length: 1,
-        offset: () => { return {top: 25}; },
+        offset: () => ({top: 25}),
     };
 
-    current_msg_list.selected_id = () => { return -1; };
+    current_msg_list.selected_id = () => -1;
-    current_msg_list.get_row = () => { return row; };
+    current_msg_list.get_row = () => row;
 
     message_list.all = {
-        all_messages: () => {
+        all_messages: () => messages,
-            return messages;
-        },
         get: (msg_id) => {
             assert.equal(msg_id, selected_id);
             return selected_message;
@@ -170,12 +168,8 @@ run_test('basics', () => {
             },
         },
         empty: () => false,
-        first: () => {
+        first: () => ({id: 900}),
-            return {id: 900};
+        last: () => ({id: 1100}),
-        },
-        last: () => {
-            return {id: 1100};
-        },
     };
 
     let cont;
@@ -214,9 +208,9 @@ run_test('basics', () => {
         'tab_bar.initialize',
     ]);
 
-    current_msg_list.selected_id = () => { return -1; };
+    current_msg_list.selected_id = () => -1;
-    current_msg_list.get_row = () => { return row; };
+    current_msg_list.get_row = () => row;
-    util.sorted_ids = () => { return []; };
+    util.sorted_ids = () => [];
 
     narrow.activate([{ operator: 'is', operand: 'private' }], {
         then_select_id: selected_id,

frontend_tests/node_tests/people.js

@@ -855,9 +855,7 @@ run_test('get_people_for_search_bar', () => {
 
     assert.equal(big_results.length, 20);
 
-    message_store.user_ids = () => {
+    message_store.user_ids = () => [1001, 1002, 1003, 1004, 1005, 1006];
-        return [1001, 1002, 1003, 1004, 1005, 1006];
-    };
 
     const small_results = people.get_people_for_search_bar('Jones');
 
@@ -1126,13 +1124,11 @@ run_test('get_visible_email', function () {
 });
 
 run_test('get_active_message_people', function () {
-    message_store.user_ids = () => {
+    message_store.user_ids = () => [
-        return [
         steven.user_id,
         maria.user_id,
         alice1.user_id,
     ];
-    };
 
     people.add_active_user(steven);
     people.add_active_user(maria);

frontend_tests/node_tests/pm_list.js

@@ -10,9 +10,7 @@ set_global('stream_popover', {
 set_global('unread', {});
 set_global('unread_ui', {});
 set_global('vdom', {
-    render: () => {
+    render: () => 'fake-dom-for-pm-list',
-        return 'fake-dom-for-pm-list';
-    },
 });
 set_global('pm_list_dom', {});
 
@@ -196,14 +194,12 @@ run_test('get_active_user_ids_string', () => {
         undefined);
 
     function set_filter_result(emails) {
-        narrow_state.filter = () => {
+        narrow_state.filter = () => ({
-            return {
             operands: (operand) => {
                 assert.equal(operand, 'pm-with');
                 return emails;
             },
-            };
+        });
-        };
     }
 
     set_filter_result([]);
@@ -224,14 +220,12 @@ run_test('is_all_privates', () => {
         pm_list.is_all_privates(),
         false);
 
-    narrow_state.filter = () => {
+    narrow_state.filter = () => ({
-        return {
         operands: (operand) => {
             assert.equal(operand, 'is');
             return ['private', 'starred'];
         },
-        };
+    });
-    };
 
     assert.equal(
         pm_list.is_all_privates(),
@@ -240,9 +234,7 @@ run_test('is_all_privates', () => {
 
 function with_fake_list(f) {
     const orig = pm_list._build_private_messages_list;
-    pm_list._build_private_messages_list = () => {
+    pm_list._build_private_messages_list = () => 'PM_LIST_CONTENTS';
-        return 'PM_LIST_CONTENTS';
-    };
     f();
     pm_list._build_private_messages_list = orig;
 }

frontend_tests/node_tests/popovers.js

@@ -63,11 +63,9 @@ const me = {
 };
 
 const target = $.create('click target');
-target.offset = () => {
+target.offset = () => ({
-    return {
     top: 10,
-    };
+});
-};
 
 const e = {
     stopPropagation: noop,
@@ -87,14 +85,12 @@ function make_image_stubber() {
 
     function stub_image() {
         const image = {};
-        image.to_$ = () => {
+        image.to_$ = () => ({
-            return {
             on: (name, f) => {
                 assert.equal(name, "load");
                 image.load_f = f;
             },
-            };
+        });
-        };
         images.push(image);
         return image;
     }

frontend_tests/node_tests/recent_senders.js

@@ -4,12 +4,8 @@ let next_id = 0;
 const messages = [];
 
 set_global('message_util', {
-    get_messages_in_topic: (stream_id, topic) => {
+    get_messages_in_topic: (stream_id, topic) => messages.filter((x) => x.stream_id === stream_id &&
-        return messages.filter((x) => {
+                   x.topic.toLowerCase() === topic.toLowerCase()),
-            return x.stream_id === stream_id &&
-                   x.topic.toLowerCase() === topic.toLowerCase();
-        });
-    },
 });
 
 run_test('process_message_for_senders', () => {

frontend_tests/node_tests/recent_topics.js

@@ -8,46 +8,36 @@ set_global('hashchange', {
     exit_overlay: noop,
 });
 set_global('stream_data', {
-    get_sub_by_id: () => {
+    get_sub_by_id: () => ({
-        return {
         color: "",
         invite_only: false,
         is_web_public: true,
-        };
+    }),
-    },
+    is_muted: () =>
-    is_muted: () => {
         // We only test via muted topics for now.
         // TODO: Make muted streams and test them.
-        return false;
+        false
-    },
+    ,
 });
 set_global('overlays', {
     open_overlay: (opts) => {
         overlays.close_callback = opts.on_close;
     },
-    recent_topics_open: () => {
+    recent_topics_open: () => true,
-        return true;
-    },
 });
 set_global('people', {
     is_my_user_id: function (id) {
         return id === 1;
     },
-    sender_info_with_small_avatar_urls_for_sender_ids: (ids) => {
+    sender_info_with_small_avatar_urls_for_sender_ids: (ids) => ids,
-        return ids;
-    },
 });
 set_global('XDate', zrequire('XDate', 'xdate'));
 set_global('timerender', {
-    last_seen_status_from_date: () => {
+    last_seen_status_from_date: () => "Just now",
-        return "Just now";
+    get_full_datetime: () => ({
-    },
-    get_full_datetime: () => {
-        return {
         date: "date",
         time: "time",
-        };
+    }),
-    },
 });
 set_global('unread', {
     unread_topic_counter: {
@@ -61,15 +51,11 @@ set_global('unread', {
     },
 });
 set_global('hash_util', {
-    by_stream_uri: () => {
+    by_stream_uri: () => "https://www.example.com",
-        return "https://www.example.com";
+    by_stream_topic_uri: () => "https://www.example.com",
-    },
-    by_stream_topic_uri: () => {
-        return "https://www.example.com";
-    },
 });
 set_global('recent_senders', {
-    get_topic_recent_senders: () => { return [1, 2]; },
+    get_topic_recent_senders: () => [1, 2],
 });
 set_global('list_render', {
     modifier: noop,
@@ -93,9 +79,7 @@ set_global('list_render', {
         return list_render;
     },
     hard_redraw: noop,
-    render_item: (item) => {
+    render_item: (item) => list_render.modifier(item),
-        return list_render.modifier(item);
-    },
 });
 
 // Custom Data
@@ -142,9 +126,7 @@ set_global('message_list', {
     },
 });
 set_global('message_store', {
-    get: (msg_id) => {
+    get: (msg_id) => messages[msg_id - 1],
-        return messages[msg_id - 1];
-    },
 });
 
 let id = 0;

frontend_tests/node_tests/schema.js

@@ -9,9 +9,7 @@ run_test('basics', () => {
         bar: schema.check_string,
     };
 
-    const check_rec = (val) => {
+    const check_rec = (val) => schema.check_record('my_rec', val, fields);
-        return schema.check_record('my_rec', val, fields);
-    };
 
     assert.equal(
         check_rec({foo: 'apple', bar: 'banana'}),
@@ -38,9 +36,7 @@ run_test('basics', () => {
         'in my_rec bar is not a string'
     );
 
-    const check_array = (val) => {
+    const check_array = (val) => schema.check_array('lst', val, schema.check_string);
-        return schema.check_array('lst', val, schema.check_string);
-    };
 
     assert.equal(
         check_array(['foo', 'bar']),

frontend_tests/node_tests/scroll_util.js

@@ -73,22 +73,18 @@ run_test('scroll_element_into_container', () => {
 
     const elem1 = {
         innerHeight: () => 25,
-        position: () => {
+        position: () => ({
-            return {
             top: 0,
-            };
+        }),
-        },
     };
     scroll_util.scroll_element_into_container(elem1, container);
     assert.equal(container.scrollTop(), 3);
 
     const elem2 = {
         innerHeight: () => 15,
-        position: () => {
+        position: () => ({
-            return {
             top: 250,
-            };
+        }),
-        },
     };
     scroll_util.scroll_element_into_container(elem2, container);
     assert.equal(container.scrollTop(), 250 - 100 + 3 + 15);

frontend_tests/node_tests/search.js

@@ -155,9 +155,7 @@ run_test('initialize', () => {
                     assert.deepEqual(raw_operators, operators);
                     assert.deepEqual(options, {trigger: 'search'});
                 };
-                search_pill.get_search_string_for_current_filter = () => {
+                search_pill.get_search_string_for_current_filter = () => search_box_val;
-                    return search_box_val;
-                };
             };
 
             operators = [{
@@ -230,9 +228,7 @@ run_test('initialize', () => {
                 assert.deepEqual(raw_operators, operators);
                 assert.deepEqual(options, {trigger: 'search'});
             };
-            search_pill.get_search_string_for_current_filter = () => {
+            search_pill.get_search_string_for_current_filter = () => search_box_val;
-                return search_box_val;
-            };
         };
 
         operators = [{
@@ -277,9 +273,7 @@ run_test('initialize', () => {
     };
 
     const search_pill_stub = $.create('.pill');
-    search_pill_stub.closest = () => {
+    search_pill_stub.closest = () => ({ data: noop });
-        return { data: noop };
-    };
     const stub_event = {
         relatedTarget: search_pill_stub,
     };

frontend_tests/node_tests/search_suggestion.js

@@ -387,11 +387,9 @@ run_test('group_suggestions', () => {
     function message(user_ids, timestamp) {
         return {
             type: 'private',
-            display_recipient: user_ids.map((id) => {
+            display_recipient: user_ids.map((id) => ({
-                return {
                 id: id,
-                };
+            })),
-            }),
             timestamp: timestamp,
         };
     }

frontend_tests/node_tests/search_suggestion_legacy.js

@@ -390,11 +390,9 @@ run_test('group_suggestions', () => {
     function message(user_ids, timestamp) {
         return {
             type: 'private',
-            display_recipient: user_ids.map((id) => {
+            display_recipient: user_ids.map((id) => ({
-                return {
                 id: id,
-                };
+            })),
-            }),
             timestamp: timestamp,
         };
     }

frontend_tests/node_tests/settings_bots.js

@@ -116,9 +116,7 @@ function set_up() {
 
     $('#config_inputbox').children = () => {
         const mock_children = {
-            hide: () => {
+            hide: () => {},
-                return;
-            },
         };
         return mock_children;
     };

frontend_tests/node_tests/settings_org.js

@@ -57,9 +57,7 @@ const _realm_logo = {
 };
 
 const _list_render = {
-    create: () => {
+    create: () => ({ init: noop }),
-        return { init: noop };
-    },
 };
 
 set_global('channel', _channel);
@@ -221,25 +219,19 @@ function test_submit_settings_form(submit_form) {
     let stubs = createSaveButtons(subsection);
     let save_button = stubs.save_button;
     save_button.attr('id', `org-submit-${subsection}`);
-    save_button.replace = () => {
+    save_button.replace = () => `${subsection}`;
-        return `${subsection}`;
-    };
 
     $("#id_realm_waiting_period_threshold").val(10);
 
     const invite_to_stream_policy_elem = $("#id_realm_invite_to_stream_policy");
     invite_to_stream_policy_elem.val('1');
     invite_to_stream_policy_elem.attr("id", 'id_realm_invite_to_stream_policy');
-    invite_to_stream_policy_elem.data = () => {
+    invite_to_stream_policy_elem.data = () => "number";
-        return "number";
-    };
 
     const create_stream_policy_elem = $("#id_realm_create_stream_policy");
     create_stream_policy_elem.val('2');
     create_stream_policy_elem.attr("id", 'id_realm_create_stream_policy');
-    create_stream_policy_elem.data = () => {
+    create_stream_policy_elem.data = () => "number";
-        return "number";
-    };
 
     const add_emoji_by_admins_only_elem = $("#id_realm_add_emoji_by_admins_only");
     add_emoji_by_admins_only_elem.val("by_anyone");
@@ -248,15 +240,11 @@ function test_submit_settings_form(submit_form) {
     const bot_creation_policy_elem = $("#id_realm_bot_creation_policy");
     bot_creation_policy_elem.val("1");
     bot_creation_policy_elem.attr('id', 'id_realm_bot_creation_policy');
-    bot_creation_policy_elem.data = () => {
+    bot_creation_policy_elem.data = () => "number";
-        return "number";
-    };
     const email_address_visibility_elem = $("#id_realm_email_address_visibility");
     email_address_visibility_elem.val("1");
     email_address_visibility_elem.attr('id', 'id_realm_email_address_visibility');
-    email_address_visibility_elem.data = () => {
+    email_address_visibility_elem.data = () => "number";
-        return "number";
-    };
 
     let subsection_elem = $(`#org-${subsection}`);
     subsection_elem.closest = () => subsection_elem;
@@ -290,15 +278,11 @@ function test_submit_settings_form(submit_form) {
     const realm_default_language_elem = $("#id_realm_default_language");
     realm_default_language_elem.val("en");
     realm_default_language_elem.attr('id', 'id_realm_default_language');
-    realm_default_language_elem.data = () => {
+    realm_default_language_elem.data = () => "string";
-        return "string";
-    };
     const realm_default_twenty_four_hour_time_elem = $("#id_realm_default_twenty_four_hour_time");
     realm_default_twenty_four_hour_time_elem.val('true');
     realm_default_twenty_four_hour_time_elem.attr('id', 'id_realm_default_twenty_four_hour_time');
-    realm_default_twenty_four_hour_time_elem.data = () => {
+    realm_default_twenty_four_hour_time_elem.data = () => "boolean";
-        return "boolean";
-    };
 
     subsection_elem = $(`#org-${subsection}`);
     subsection_elem.closest = () => subsection_elem;
@@ -732,11 +716,9 @@ function test_discard_changes_button(discard_changes) {
 run_test('set_up', () => {
     const callbacks = {};
 
-    const set_callback = (name) => {
+    const set_callback = (name) => (f) => {
-        return (f) => {
         callbacks[name] = f;
     };
-    };
 
     const verify_realm_domains = simulate_realm_domains_table();
     page_params.realm_available_video_chat_providers = {
@@ -784,12 +766,10 @@ run_test('set_up', () => {
     };
 
     const dropdown_list_widget_backup = dropdown_list_widget;
-    window.dropdown_list_widget = () => {
+    window.dropdown_list_widget = () => ({
-        return {
         render: noop,
         update: noop,
-        };
+    });
-    };
     $("#id_realm_message_content_edit_limit_minutes").set_parent($.create('<stub edit limit parent>'));
     $("#id_realm_message_content_delete_limit_minutes").set_parent($.create('<stub delete limit parent>'));
     $("#id_realm_message_retention_days").set_parent($.create('<stub retention period parent>'));
@@ -1018,9 +998,7 @@ run_test('misc', () => {
     dropdown_list_parent.set_find_results('.dropdown_list_reset_button:not([disabled])', $.create('<disable button>'));
     widget_settings.forEach((name) => {
         const elem = $.create(`#${name}_widget #${name}_name`);
-        elem.closest = () => {
+        elem.closest = () => dropdown_list_parent;
-            return dropdown_list_parent;
-        };
     });
 
     // We do not define any settings we need in page_params yet, but we don't need to for this test.

frontend_tests/node_tests/stream_data.js

@@ -1075,7 +1075,7 @@ run_test('all_topics_in_cache', () => {
 
     message_list.all.data.add_messages(messages);
     assert.equal(stream_data.all_topics_in_cache(sub), false);
-    message_list.all.data.fetch_status.has_found_newest = () => {return true;};
+    message_list.all.data.fetch_status.has_found_newest = () => true;
     assert.equal(stream_data.all_topics_in_cache(sub), true);
 
     sub.first_message_id = 0;

frontend_tests/node_tests/stream_list.js

@@ -718,9 +718,7 @@ run_test('refresh_pin', () => {
     const li_stub = $.create('li stub');
     li_stub.length = 0;
 
-    global.stub_templates(() => {
+    global.stub_templates(() => ({to_$: () => li_stub}));
-        return {to_$: () => li_stub};
-    });
 
     stream_list.update_count_in_dom = noop;
     $('#stream_filters').append = noop;

frontend_tests/node_tests/stream_topic_history.js

@@ -92,9 +92,7 @@ run_test('is_complete_for_stream_id', () => {
                 has_found_newest: () => true,
             },
         },
-        first: () => {
+        first: () => ({id: 5}),
-            return {id: 5};
-        },
     };
 
     assert.equal(
@@ -102,9 +100,7 @@ run_test('is_complete_for_stream_id', () => {
         true);
 
     // Now simulate a more recent message id.
-    message_list.all.first = () => {
+    message_list.all.first = () => ({id: sub.first_message_id + 1});
-        return {id: sub.first_message_id + 1};
-    };
 
     // Note that we'll return `true` here due to
     // fetched_stream_ids having the stream_id now.

frontend_tests/node_tests/topic_list_data.js

@@ -80,9 +80,7 @@ run_test('get_list_info unreads', () => {
 
     // Going forward, we just stub get_recent_topic_names
     // for simpler test setup.
-    stream_topic_history.get_recent_topic_names = () => {
+    stream_topic_history.get_recent_topic_names = () => _.range(15).map((i) => 'topic ' + i);
-        return _.range(15).map((i) => 'topic ' + i);
-    };
 
     const unread_cnt = new Map();
     unread.num_unread_for_topic = (stream_id, topic_name) => {

frontend_tests/node_tests/upgrade.js

@@ -88,17 +88,11 @@ run_test("initialize", () => {
         assert.equal(schedule, "monthly");
     };
 
-    $('input[type=radio][name=license_management]:checked').val = () => {
+    $('input[type=radio][name=license_management]:checked').val = () => document.querySelector("input[type=radio][name=license_management]:checked").value;
-        return document.querySelector("input[type=radio][name=license_management]:checked").value;
-    };
 
-    $('input[type=radio][name=schedule]:checked').val = () => {
+    $('input[type=radio][name=schedule]:checked').val = () => document.querySelector("input[type=radio][name=schedule]:checked").value;
-        return document.querySelector("input[type=radio][name=schedule]:checked").value;
-    };
 
-    $("#autopay-form").data = (key) => {
+    $("#autopay-form").data = (key) => document.querySelector("#autopay-form").getAttribute("data-" + key);
-        return document.querySelector("#autopay-form").getAttribute("data-" + key);
-    };
 
     jquery_init();
 
@@ -110,16 +104,12 @@ run_test("initialize", () => {
     const invoice_click_handler = $('#invoice-button').get_on_handler('click');
     const request_sponsorship_click_handler = $('#sponsorship-button').get_on_handler('click');
 
-    helpers.is_valid_input = () => {
+    helpers.is_valid_input = () => true;
-        return true;
-    };
 
     add_card_click_handler(e);
     invoice_click_handler(e);
 
-    helpers.is_valid_input = () => {
+    helpers.is_valid_input = () => false;
-        return false;
-    };
     add_card_click_handler(e);
     invoice_click_handler(e);
 

frontend_tests/node_tests/upload.js

@@ -436,23 +436,17 @@ run_test('uppy_events', () => {
             on: (event_name, callback) => {
                 callbacks[event_name] = callback;
             },
-            getFiles: () => {
+            getFiles: () => [...files],
-                return [...files];
-            },
             removeFile: (file_id) => {
-                files = files.filter((file) => {
+                files = files.filter((file) => file.id !== file_id);
-                    return file.id !== file_id;
-                });
             },
-            getState: () => {
+            getState: () => ({
-                return {
                 info: {
                     type: state.type,
                     details: state.details,
                     message: state.message,
                 },
-                };
+            }),
-            },
         };
     }
     uppy_stub.Plugin = plugin_stub;

frontend_tests/node_tests/vdom.js

@@ -102,13 +102,9 @@ run_test('attribute updates', () => {
 });
 
 function make_child(i, name) {
-    const render = () => {
+    const render = () => '<li>' + name + '</li>';
-        return '<li>' + name + '</li>';
-    };
 
-    const eq = (other) => {
+    const eq = (other) => name === other.name;
-        return name === other.name;
-    };
 
     return {
         key: i,
@@ -207,10 +203,8 @@ run_test('partial updates', () => {
 
     let patched_html;
 
-    find = () => {
+    find = () => ({
-        return {
+        children: () => ({
-            children: () => {
-                return {
             eq: (i) => {
                 assert.equal(i, 0);
                 return {
@@ -219,10 +213,8 @@ run_test('partial updates', () => {
                     },
                 };
             },
-                };
+        }),
-            },
+    });
-        };
-    };
 
     const new_nodes = make_children([1, 2, 3]);
     new_nodes[0] = make_child(1, 'modified1');

frontend_tests/node_tests/zjquery.js

@@ -212,8 +212,8 @@ run_test('extensions', () => {
     // using direct syntax:
 
     const rect = $.create('rectangle');
-    rect.width = () => { return 5; };
+    rect.width = () => 5;
-    rect.height = () => { return 7; };
+    rect.height = () => 7;
 
     assert.equal(rect.width(), 5);
     assert.equal(rect.height(), 7);

frontend_tests/zjsunit/index.js

@@ -17,9 +17,7 @@ const _ = global._;
 
 // Create a helper function to avoid sneaky delays in tests.
 function immediate(f) {
-    return () => {
+    return () => f();
-        return f();
-    };
 }
 
 // Find the files we need to run.

frontend_tests/zjsunit/markdown_assert.js

@@ -165,12 +165,10 @@ class MarkdownComparer {
 
 function returnComparer() {
     if (!_markdownComparerInstance) {
-        _markdownComparerInstance = new MarkdownComparer((actual, expected) => {
+        _markdownComparerInstance = new MarkdownComparer((actual, expected) => [
-            return [
             "Actual and expected output do not match.  Showing diff",
             mdiff.diff_strings(actual, expected),
-            ].join('\n');
+        ].join('\n'));
-        });
     }
     return _markdownComparerInstance;
 }

frontend_tests/zjsunit/mdiff.js

@@ -19,9 +19,9 @@ function apply_color(input_string, changes) {
     input_string = input_string.slice(2);
 
     const formatter = new Map([
-        ["delete", (string) => { return "\u001b[31m" + string + "\u001b[0m"; }],
+        ["delete", (string) => "\u001b[31m" + string + "\u001b[0m"],
-        ["insert", (string) => { return "\u001b[32m" + string + "\u001b[0m"; }],
+        ["insert", (string) => "\u001b[32m" + string + "\u001b[0m"],
-        ["replace", (string) => { return "\u001b[33m" + string + "\u001b[0m"; }],
+        ["replace", (string) => "\u001b[33m" + string + "\u001b[0m"],
     ]);
     changes.forEach((change) => {
         if (formatter.has(change.tag)) {
@@ -114,9 +114,7 @@ function diff_strings(string_0, string_1) {
         }
     });
 
-    const emphasize_codes = (string) => {
+    const emphasize_codes = (string) => "\u001b[34m" + string.slice(0, 1) + "\u001b[0m" + string.slice(1);
-        return "\u001b[34m" + string.slice(0, 1) + "\u001b[0m" + string.slice(1);
-    };
     output_lines = output_lines.map(emphasize_codes);
 
     return output_lines.join("\n");

frontend_tests/zjsunit/zblueslip.js

@@ -75,9 +75,7 @@ exports.make_zblueslip = function () {
         }
     };
 
-    lib.get_test_logs = (name) => {
+    lib.get_test_logs = (name) => lib.test_logs[name];
-        return lib.test_logs[name];
-    };
 
     // Create logging functions
     for (const name of names) {
@@ -113,13 +111,9 @@ exports.make_zblueslip = function () {
         return ex.message;
     };
 
-    lib.start_timing = () => {
+    lib.start_timing = () => () => {};
-        return () => {};
-    };
 
-    lib.preview_node = (node) => {
+    lib.preview_node = (node) => 'node:' + node;
-        return 'node:' + node;
-    };
 
     return lib;
 };

static/js/compose.js

@@ -916,9 +916,7 @@ exports.warn_if_mentioning_unsubscribed_user = function (mentioned) {
         const error_area = $("#compose_invite_users");
         const existing_invites_area = $('#compose_invite_users .compose_invite_user');
 
-        const existing_invites = Array.from($(existing_invites_area), (user_row) => {
+        const existing_invites = Array.from($(existing_invites_area), (user_row) => parseInt($(user_row).data('user-id'), 10));
-            return parseInt($(user_row).data('user-id'), 10);
-        });
 
         if (!existing_invites.includes(user_id)) {
             const context = {

static/js/composebox_typeahead.js

@@ -442,13 +442,9 @@ exports.get_pm_people = function (query) {
 exports.get_person_suggestions = function (query, opts) {
     query = typeahead.clean_query_lowercase(query);
 
-    const person_matcher = (item) => {
+    const person_matcher = (item) => exports.query_matches_person(query, item);
-        return exports.query_matches_person(query, item);
-    };
 
-    const group_matcher = (item) => {
+    const group_matcher = (item) => query_matches_name_description(query, item);
-        return query_matches_name_description(query, item);
-    };
 
     function filter_persons(all_persons) {
         let persons;

static/js/filter.js

@@ -665,9 +665,7 @@ Filter.prototype = {
     },
 
     _fix_redundant_is_private: function (terms) {
-        const is_pm_with = (term) => {
+        const is_pm_with = (term) => Filter.term_type(term) === 'pm-with';
-            return Filter.term_type(term) === 'pm-with';
-        };
 
         if (!terms.some(is_pm_with)) {
             return terms;

static/js/list_render.js

@@ -45,9 +45,7 @@ exports.get_filtered_items = (value, list, opts) => {
         return opts.filter.filterer(list, value);
     }
 
-    const predicate = (item) => {
+    const predicate = (item) => opts.filter.predicate(item, value);
-        return opts.filter.predicate(item, value);
-    };
 
     if (get_item) {
         const result = [];
@@ -65,8 +63,7 @@ exports.get_filtered_items = (value, list, opts) => {
     return list.filter(predicate);
 };
 
-exports.alphabetic_sort = (prop) => {
+exports.alphabetic_sort = (prop) => function (a, b) {
-    return function (a, b) {
     // The conversion to uppercase helps make the sorting case insensitive.
     const str1 = a[prop].toUpperCase();
     const str2 = b[prop].toUpperCase();
@@ -79,10 +76,8 @@ exports.alphabetic_sort = (prop) => {
 
     return -1;
 };
-};
 
-exports.numeric_sort = (prop) => {
+exports.numeric_sort = (prop) => function (a, b) {
-    return function (a, b) {
     if (parseFloat(a[prop]) > parseFloat(b[prop])) {
         return 1;
     } else if (parseFloat(a[prop]) === parseFloat(b[prop])) {
@@ -91,7 +86,6 @@ exports.numeric_sort = (prop) => {
 
     return -1;
 };
-};
 
 exports.valid_filter_opts = (opts) => {
     if (!opts.filter) {

static/js/message_util.js

@@ -49,11 +49,9 @@ exports.get_messages_in_topic = function (stream_id, topic) {
     // all the messages. Please only use it in case of
     // very rare events like topic edits. Its primary
     // use case is the new experimental Recent Topics UI.
-    return message_list.all.all_messages().filter((x) => {
+    return message_list.all.all_messages().filter((x) => x.type === 'stream' &&
-        return x.type === 'stream' &&
                x.stream_id === stream_id &&
-               x.topic.toLowerCase() === topic.toLowerCase();
+               x.topic.toLowerCase() === topic.toLowerCase());
-    });
 };
 
 window.message_util = exports;

static/js/pm_list_dom.js

@@ -1,13 +1,9 @@
 const render_pm_list_item = require('../templates/pm_list_item.hbs');
 
 exports.keyed_pm_li = (convo) => {
-    const render = () => {
+    const render = () => render_pm_list_item(convo);
-        return render_pm_list_item(convo);
-    };
 
-    const eq = (other) => {
+    const eq = (other) => _.isEqual(convo, other.convo);
-        return _.isEqual(convo, other.convo);
-    };
 
     const key = convo.user_ids_string;
 

static/js/recent_senders.js

@@ -114,7 +114,7 @@ exports.get_topic_recent_senders = function (stream_id, topic) {
     }
 
     const sorted_senders = Array.from(sender_message_ids.entries()).sort(
-        (s1, s2) => { return s1[1] - s2[1]; }
+        (s1, s2) => s1[1] - s2[1]
     );
     const recent_senders = [];
     for (const item of sorted_senders) {

static/js/settings_org.js

@@ -558,7 +558,7 @@ exports.init_dropdown_widgets = () => {
             exports.save_discard_widget_status_handler($(`#org-notifications`));
         },
         default_text: i18n.t("Disabled"),
-        render_text: (x) => {return `#${x}`;},
+        render_text: (x) => `#${x}`,
         null_value: -1,
     };
     exports.notifications_stream_widget = dropdown_list_widget(
@@ -575,12 +575,10 @@ exports.init_dropdown_widgets = () => {
                       notification_stream_options));
     exports.default_code_language_widget = dropdown_list_widget({
         widget_name: 'realm_default_code_block_language',
-        data: Object.keys(pygments_data.langs).map((x) => {
+        data: Object.keys(pygments_data.langs).map((x) => ({
-            return {
             name: x,
             value: x,
-            };
+        })),
-        }),
         value: page_params.realm_default_code_block_language,
         on_update: () => {
             exports.save_discard_widget_status_handler($(`#org-other-settings`));

static/js/topic_list.js

@@ -55,13 +55,9 @@ exports.zoom_out = function () {
 };
 
 exports.keyed_topic_li = (convo) => {
-    const render = () => {
+    const render = () => render_topic_list_item(convo);
-        return render_topic_list_item(convo);
-    };
 
-    const eq = (other) => {
+    const eq = (other) => _.isEqual(convo, other.convo);
-        return _.isEqual(convo, other.convo);
-    };
 
     const key = 't:' + convo.topic_name;
 
@@ -74,16 +70,12 @@ exports.keyed_topic_li = (convo) => {
 };
 
 exports.more_li = (more_topics_unreads) => {
-    const render = () => {
+    const render = () => render_more_topics({
-        return render_more_topics({
         more_topics_unreads: more_topics_unreads,
     });
-    };
 
-    const eq = (other) => {
+    const eq = (other) => other.more_items &&
-        return other.more_items &&
             more_topics_unreads === other.more_topics_unreads;
-    };
 
     const key = 'more';
 
@@ -97,13 +89,9 @@ exports.more_li = (more_topics_unreads) => {
 };
 
 exports.spinner_li = () => {
-    const render = () => {
+    const render = () => render_more_topics_spinner();
-        return render_more_topics_spinner();
-    };
 
-    const eq = (other) => {
+    const eq = (other) => other.spinner;
-        return other.spinner;
-    };
 
     const key = 'more';
 

static/js/vdom.js

@@ -16,12 +16,10 @@ exports.eq_array = (a, b, eq) => {
     return a.every((item, i) => eq(item, b[i]));
 };
 
-exports.ul = (opts) => {
+exports.ul = (opts) => ({
-    return {
     tag_name: 'ul',
     opts: opts,
-    };
+});
-};
 
 exports.render_tag = (tag) => {
     /*