eslint: Enable `conditionalAssign` config of no-trailing-spaces rule.

.eslintrc.json

@@ -280,12 +280,7 @@
         "no-eq-null": 2,
         "no-eval": 2,
         "no-ex-assign": 2,
-        "no-extra-parens": ["error", "all",
+        "no-extra-parens": ["error", "all"],
-            {
-                "conditionalAssign": false,
-                "nestedBinaryExpressions": false
-            }
-        ],
         "no-extra-semi": 2,
         "no-fallthrough": 2,
         "no-floating-decimal": 2,

frontend_tests/casper_lib/common.js

@@ -319,7 +319,7 @@ exports.then_send_many = function (msgs) {
 exports.wait_for_receive = function (step) {
     // Wait until the last send or get_events result was more than 1000 ms ago.
     casper.waitFor(function () {
-        return (timestamp() - last_send_or_update) > 1000;
+        return timestamp() - last_send_or_update > 1000;
     }, step);
 };
 

frontend_tests/zjsunit/zjquery.js

@@ -401,15 +401,15 @@ exports.make_zjquery = function (opts) {
         }
 
         var valid_selector =
-            ('<#.'.indexOf(selector[0]) >= 0) ||
+            '<#.'.indexOf(selector[0]) >= 0 ||
-            (selector === 'window-stub') ||
+            selector === 'window-stub' ||
-            (selector === 'document-stub') ||
+            selector === 'document-stub' ||
-            (selector === 'body') ||
+            selector === 'body' ||
-            (selector === 'html') ||
+            selector === 'html' ||
             selector.location ||
-            (selector.indexOf('#') >= 0) ||
+            selector.indexOf('#') >= 0 ||
-            (selector.indexOf('.') >= 0) ||
+            selector.indexOf('.') >= 0 ||
-            (selector.indexOf('[') >= 0 && selector.indexOf(']') >= selector.indexOf('['));
+            selector.indexOf('[') >= 0 && selector.indexOf(']') >= selector.indexOf('[');
 
         assert(valid_selector,
                'Invalid selector: ' + selector +

static/js/activity.js

@@ -122,7 +122,7 @@ exports.process_loaded_messages = function (messages) {
         if (huddle_string) {
             var old_timestamp = huddle_timestamps.get(huddle_string);
 
-            if (!old_timestamp || (old_timestamp < message.timestamp)) {
+            if (!old_timestamp || old_timestamp < message.timestamp) {
                 huddle_timestamps.set(huddle_string, message.timestamp);
                 need_resize = true;
             }

static/js/attachments_ui.js

@@ -29,8 +29,8 @@ function bytes_to_size(bytes, kb_with_1024_bytes) {
     }
     var i = parseInt(Math.floor(Math.log(bytes) / Math.log(kb_size)), 10);
     var size = Math.round(bytes / Math.pow(kb_size, i));
-    if ((i > 0) && (size < 10)) {
+    if (i > 0 && size < 10) {
-        size = Math.round((bytes / Math.pow(kb_size, i)) * 10) / 10;
+        size = Math.round(bytes / Math.pow(kb_size, i) * 10) / 10;
     }
     return size + ' ' + sizes[i];
 }

static/js/click_handlers.js

@@ -58,7 +58,7 @@ exports.initialize = function () {
         return target.is("a") || target.is("img.message_inline_image") || target.is("img.twitter-avatar") ||
             target.is("div.message_length_controller") || target.is("textarea") || target.is("input") ||
             target.is("i.edit_content_button") ||
-            (target.is(".highlight") && target.parent().is("a"));
+            target.is(".highlight") && target.parent().is("a");
     }
 
     function initialize_long_tap() {
@@ -121,7 +121,7 @@ exports.initialize = function () {
         // work nearly perfectly.  Once we no longer need to support
         // older browsers, we may be able to use the window.selection
         // API instead.
-        if ((drag.val < 5 && drag.time < 150) || drag.val < 2) {
+        if (drag.val < 5 && drag.time < 150 || drag.val < 2) {
             var row = $(this).closest(".message_row");
             var id = rows.id(row);
 

static/js/colorspace.js

@@ -26,8 +26,8 @@ exports.rgb_luminance = function (channel) {
 // http://en.wikipedia.org/wiki/Lab_color_space#Forward_transformation
 exports.luminance_to_lightness = function (luminance) {
     var v;
-    if (luminance <= (216 / 24389)) {
+    if (luminance <= 216 / 24389) {
-        v = (841 / 108) * luminance + (4 / 29);
+        v = 841 / 108 * luminance + 4 / 29;
     } else {
         v = Math.pow(luminance, 1 / 3);
     }

static/js/common.js

@@ -48,7 +48,7 @@ exports.password_quality = function (password, bar, password_field) {
 
         // The bar bottoms out at 10% so there's always something
         // for the user to see.
-        bar.width(((90 * bar_progress) + 10) + '%')
+        bar.width(90 * bar_progress + 10 + '%')
             .removeClass('bar-success bar-danger')
             .addClass(acceptable ? 'bar-success' : 'bar-danger');
     }

static/js/compose_actions.js

@@ -33,8 +33,8 @@ function get_focus_area(msg_type, opts) {
     // Set focus to "Topic" when narrowed to a stream+topic and "New topic" button clicked.
     if (msg_type === 'stream' && opts.stream && !opts.subject) {
         return 'subject';
-    } else if ((msg_type === 'stream' && opts.stream)
+    } else if (msg_type === 'stream' && opts.stream
-               || (msg_type === 'private' && opts.private_message_recipient)) {
+               || msg_type === 'private' && opts.private_message_recipient) {
         if (opts.trigger === "new topic button") {
             return 'subject';
         }
@@ -181,12 +181,12 @@ function fill_in_opts_from_current_narrowed_view(msg_type, opts) {
 }
 
 function same_recipient_as_before(msg_type, opts) {
-    return (compose_state.get_message_type() === msg_type) &&
+    return compose_state.get_message_type() === msg_type &&
-            ((msg_type === "stream" &&
+            (msg_type === "stream" &&
               opts.stream === compose_state.stream_name() &&
-              opts.subject === compose_state.subject()) ||
+              opts.subject === compose_state.subject() ||
-             (msg_type === "private" &&
+             msg_type === "private" &&
-              opts.private_message_recipient === compose_state.recipient()));
+              opts.private_message_recipient === compose_state.recipient());
 }
 
 exports.start = function (msg_type, opts) {
@@ -202,9 +202,9 @@ exports.start = function (msg_type, opts) {
     // If we are invoked by a compose hotkey (c or x) or new topic button
     // or sidebar stream actions (in stream popover), do not assume that we know what
     // the message's topic or PM recipient should be.
-    if ((opts.trigger === "compose_hotkey") ||
+    if (opts.trigger === "compose_hotkey" ||
-        (opts.trigger === "new topic button") ||
+        opts.trigger === "new topic button" ||
-        (opts.trigger === "sidebar stream actions")) {
+        opts.trigger === "sidebar stream actions") {
         opts.subject = '';
         opts.private_message_recipient = '';
     }
@@ -280,7 +280,7 @@ exports.respond_to_message = function (opts) {
         var first_operator = first_term.operator;
         var first_operand = first_term.operand;
 
-        if ((first_operator === "stream") && !stream_data.is_subscribed(first_operand)) {
+        if (first_operator === "stream" && !stream_data.is_subscribed(first_operand)) {
             compose.nonexistent_stream_reply_error();
             return;
         }

static/js/compose_ui.js

@@ -8,7 +8,7 @@ exports.autosize_textarea = function () {
 
 exports.smart_insert = function (textarea, syntax) {
     function is_space(c) {
-        return (c === ' ') || (c === '\t') || (c === '\n');
+        return c === ' ' || c === '\t' || c === '\n';
     }
 
     var pos = textarea.caret();

static/js/composebox_typeahead.js

@@ -114,7 +114,7 @@ var nextFocus = false;
 function handle_keydown(e) {
     var code = e.keyCode || e.which;
 
-    if (code === 13 || (code === 9 && !e.shiftKey)) { // Enter key or tab key
+    if (code === 13 || code === 9 && !e.shiftKey) { // Enter key or tab key
         if (e.target.id === "stream" || e.target.id === "subject" || e.target.id === "private_message_recipient") {
             // For enter, prevent the form from submitting
             // For tab, prevent the focus from changing again
@@ -228,7 +228,7 @@ function handle_keydown(e) {
 
 function handle_keyup(e) {
     var code = e.keyCode || e.which;
-    if (code === 13 || (code === 9 && !e.shiftKey)) { // Enter key or tab key
+    if (code === 13 || code === 9 && !e.shiftKey) { // Enter key or tab key
         if (nextFocus) {
             ui_util.focus_on(nextFocus);
             nextFocus = false;

static/js/drafts.js

@@ -64,7 +64,7 @@ var draft_model = (function () {
 exports.draft_model = draft_model;
 
 exports.snapshot_message = function () {
-    if (!compose_state.composing() || (compose_state.message_content() === "")) {
+    if (!compose_state.composing() || compose_state.message_content() === "") {
         // If you aren't in the middle of composing the body of a
         // message, don't try to snapshot.
         return;
@@ -126,11 +126,11 @@ exports.restore_draft = function (draft_id) {
     }
 
     var draft_copy = _.extend({}, draft);
-    if ((draft_copy.type === "stream" &&
+    if (draft_copy.type === "stream" &&
          draft_copy.stream.length > 0 &&
-             draft_copy.subject.length > 0) ||
+             draft_copy.subject.length > 0 ||
-                 (draft_copy.type === "private" &&
+                 draft_copy.type === "private" &&
-                  draft_copy.reply_to.length > 0)) {
+                  draft_copy.reply_to.length > 0) {
         draft_copy = _.extend({replying_to_message: draft_copy},
                               draft_copy);
     }

static/js/emoji_picker.js

@@ -274,7 +274,7 @@ function get_alias_to_be_used(message_id, emoji_name) {
     }
     var user_id = page_params.user_id;
     var reaction = _.find(message.reactions, function (reaction) {
-        return (reaction.user.id === user_id) && _.contains(aliases, reaction.emoji_name);
+        return reaction.user.id === user_id && _.contains(aliases, reaction.emoji_name);
     });
     if (reaction) {
         return reaction.emoji_name;
@@ -322,7 +322,7 @@ exports.toggle_selected_emoji = function () {
 };
 
 function round_off_to_previous_multiple(number_to_round, multiple) {
-    return number_to_round - (number_to_round % multiple);
+    return number_to_round - number_to_round % multiple;
 }
 
 function reset_emoji_showcase() {
@@ -445,7 +445,7 @@ exports.navigate = function (event_name) {
         var filter_text = $(".emoji-popover-filter").val();
         var is_cursor_at_end = $(".emoji-popover-filter").caret() === filter_text.length;
         if (event_name === "down_arrow" ||
-           (is_cursor_at_end && event_name === "right_arrow")) {
+           is_cursor_at_end && event_name === "right_arrow") {
             selected_emoji.focus();
             if (current_section === 0 && current_index < 6) {
                 $(".emoji-popover-emoji-map").scrollTop(0);
@@ -459,8 +459,8 @@ exports.navigate = function (event_name) {
             return true;
         }
         return false;
-    } else if ((current_section === 0 && current_index < 6 && event_name === 'up_arrow') ||
+    } else if (current_section === 0 && current_index < 6 && event_name === 'up_arrow' ||
-               (current_section === 0 && current_index === 0 && event_name === 'left_arrow')) {
+               current_section === 0 && current_index === 0 && event_name === 'left_arrow') {
         if (selected_emoji) {
             // In this case, we're move up into the reaction
             // filter. Here, we override the default browser

static/js/filter.js

@@ -36,8 +36,8 @@ function zephyr_topic_name_match(message, operand) {
 
 function message_in_home(message) {
     if (message.type === "private" || message.mentioned ||
-        (page_params.narrow_stream !== undefined &&
+        page_params.narrow_stream !== undefined &&
-         message.stream.toLowerCase() === page_params.narrow_stream.toLowerCase())) {
+         message.stream.toLowerCase() === page_params.narrow_stream.toLowerCase()) {
         return true;
     }
 
@@ -347,7 +347,7 @@ Filter.prototype = {
 
     operands: function (operator) {
         return _.chain(this._operators)
-            .filter(function (elem) { return !elem.negated && (elem.operator === operator); })
+            .filter(function (elem) { return !elem.negated && elem.operator === operator; })
             .map(function (elem) { return elem.operand; })
             .value();
     },
@@ -606,7 +606,7 @@ function describe_unescaped(operators) {
 
     if (operators.length >= 2) {
         var is = function (term, expected) {
-            return (term.operator === expected) && !term.negated;
+            return term.operator === expected && !term.negated;
         };
 
         if (is(operators[0], 'stream') && is(operators[1], 'topic')) {

static/js/floating_recipient_bar.js

@@ -93,7 +93,7 @@ exports.update = function () {
     // covering up a label that already exists).
     var header_height = $(current_label).find('.message_header').safeOuterHeight();
     if (floating_recipient_bar_bottom <=
-        (current_label.offset().top + header_height)) {
+        current_label.offset().top + header_height) {
         // hide floating_recipient_bar and use .temp-show-date to force display
         // of the recipient_row_date belonging to the current recipient_bar
         $('.recipient_row_date', current_label).addClass('temp-show-date');

static/js/hash_util.js

@@ -12,7 +12,7 @@ exports.encodeHashComponent = function (str) {
 };
 
 exports.encode_operand = function (operator, operand) {
-    if ((operator === 'group-pm-with') || (operator === 'pm-with') || (operator === 'sender')) {
+    if (operator === 'group-pm-with' || operator === 'pm-with' || operator === 'sender') {
         var slug = people.emails_to_slug(operand);
         if (slug) {
             return slug;
@@ -39,7 +39,7 @@ exports.decodeHashComponent = function (str) {
 };
 
 exports.decode_operand = function (operator, operand) {
-    if ((operator === 'group-pm-with') || (operator === 'pm-with') || (operator === 'sender')) {
+    if (operator === 'group-pm-with' || operator === 'pm-with' || operator === 'sender') {
         var emails = people.slug_to_emails(operand);
         if (emails) {
             return emails;

static/js/hashchange.js

@@ -112,9 +112,9 @@ function do_hashchange(from_reload) {
     // The second case is for handling the fact that some browsers
     // automatically convert '#' to '' when you change the hash to '#'.
     if (window.location.hash === expected_hash ||
-        (expected_hash !== undefined &&
+        expected_hash !== undefined &&
          window.location.hash.replace(/^#/, '') === '' &&
-         expected_hash.replace(/^#/, '') === '')) {
+         expected_hash.replace(/^#/, '') === '') {
         return false;
     }
 

static/js/hotkey.js

@@ -519,7 +519,7 @@ exports.process_hotkey = function (e, hotkey) {
         }
     }
 
-    if ((actions_dropdown_hotkeys.indexOf(event_name) !== -1) && popovers.actions_popped()) {
+    if (actions_dropdown_hotkeys.indexOf(event_name) !== -1 && popovers.actions_popped()) {
         popovers.actions_menu_handle_keyboard(event_name);
         return true;
     }

static/js/hotspots.js

@@ -97,14 +97,14 @@ function place_popover(hotspot) {
     case TOP:
         popover_offset = {
             top: -(popover_height + arrow_offset),
-            left: (el_width / 2) - (popover_width / 2),
+            left: el_width / 2 - popover_width / 2,
         };
         arrow_placement = 'bottom';
         break;
 
     case LEFT:
         popover_offset = {
-            top: (el_height / 2) - (popover_height / 2),
+            top: el_height / 2 - popover_height / 2,
             left: -(popover_width + arrow_offset),
         };
         arrow_placement = 'right';
@@ -113,14 +113,14 @@ function place_popover(hotspot) {
     case BOTTOM:
         popover_offset = {
             top: el_height + arrow_offset,
-            left: (el_width / 2) - (popover_width / 2),
+            left: el_width / 2 - popover_width / 2,
         };
         arrow_placement = 'top';
         break;
 
     case RIGHT:
         popover_offset = {
-            top: (el_height / 2) - (popover_height / 2),
+            top: el_height / 2 - popover_height / 2,
             left: el_width + arrow_offset,
         };
         arrow_placement = 'left';

static/js/invite.js

@@ -11,9 +11,9 @@ function update_subscription_checkboxes() {
 
     _.each(stream_data.invite_streams(), function (value) {
         var is_notifications_stream = value === page_params.notifications_stream;
-        if ((stream_data.subscribed_streams().length === 1) ||
+        if (stream_data.subscribed_streams().length === 1 ||
             !is_notifications_stream ||
-            (is_notifications_stream && stream_data.get_invite_only(value))) {
+            is_notifications_stream && stream_data.get_invite_only(value)) {
             // You can't actually elect not to invite someone to the
             // notifications stream. We won't even show it as a choice unless
             // it's the only stream you have, or if you've made it private.

static/js/lightbox_canvas.js

@@ -66,8 +66,8 @@ var LightboxCanvas = (function () {
             // where the last `layerX` and `layerY` movements since the last
             // `mousemove` event in this `mousedown` event were registered.
             var polyfillMouseMovement = function (e) {
-                e.movementX = (e.layerX - lastPosition.x) || 0;
+                e.movementX = e.layerX - lastPosition.x || 0;
-                e.movementY = (e.layerY - lastPosition.y) || 0;
+                e.movementY = e.layerY - lastPosition.y || 0;
 
                 lastPosition = {
                     x: e.layerX,
@@ -103,7 +103,7 @@ var LightboxCanvas = (function () {
                 // normalizedDelta = delta * (1 / 20) * 1 = 0.4
                 // zoom = zoom * (0.4 / 100) + 1
                 var zoom = meta.zoom * (
-                    (meta.speed * meta.internalSpeedMultiplier * delta / 100) + 1
+                    meta.speed * meta.internalSpeedMultiplier * delta / 100 + 1
                 );
 
                 funcs.setZoom(meta, zoom);
@@ -201,18 +201,18 @@ var LightboxCanvas = (function () {
 
         displayImage: function (canvas, context, meta) {
             meta.coords.x = Math.max(1 / (meta.zoom * 2), meta.coords.x);
-            meta.coords.x = Math.min(1 - (1 / (meta.zoom * 2)), meta.coords.x);
+            meta.coords.x = Math.min(1 - 1 / (meta.zoom * 2), meta.coords.x);
 
             meta.coords.y = Math.max(1 / (meta.zoom * 2), meta.coords.y);
-            meta.coords.y = Math.min(1 - (1 / (meta.zoom * 2)), meta.coords.y);
+            meta.coords.y = Math.min(1 - 1 / (meta.zoom * 2), meta.coords.y);
 
             var c = {
                 x: meta.coords.x - 1,
                 y: meta.coords.y - 1,
             };
 
-            var x = (meta.zoom * c.x * canvas.width) + canvas.width / 2;
+            var x = meta.zoom * c.x * canvas.width + canvas.width / 2;
-            var y = (meta.zoom * c.y * canvas.height) + canvas.height / 2;
+            var y = meta.zoom * c.y * canvas.height + canvas.height / 2;
             var w = canvas.width * meta.zoom;
             var h = canvas.height * meta.zoom;
 
@@ -244,7 +244,7 @@ var LightboxCanvas = (function () {
                 canvas.style.width = parent.width + "px";
 
 
-                canvas.height = (parent.width / meta.ratio) * 2;
+                canvas.height = parent.width / meta.ratio * 2;
                 canvas.style.height = parent.width / meta.ratio + "px";
             } else {
                 canvas.height = parent.height * 2;

static/js/message_edit.js

@@ -21,8 +21,8 @@ function is_topic_editable(message, edit_limit_seconds_buffer) {
     edit_limit_seconds_buffer = edit_limit_seconds_buffer || 0;
 
     // TODO: Change hardcoded value (24 hrs) to be realm setting
-    return message.sent_by_me || (page_params.realm_allow_community_topic_editing
+    return message.sent_by_me || page_params.realm_allow_community_topic_editing
-        && (86400 + edit_limit_seconds_buffer + now.diffSeconds(message.timestamp * 1000) > 0));
+        && 86400 + edit_limit_seconds_buffer + now.diffSeconds(message.timestamp * 1000) > 0;
 }
 
 function get_editability(message, edit_limit_seconds_buffer) {
@@ -57,8 +57,8 @@ function get_editability(message, edit_limit_seconds_buffer) {
     }
 
     var now = new XDate();
-    if ((page_params.realm_message_content_edit_limit_seconds + edit_limit_seconds_buffer +
+    if (page_params.realm_message_content_edit_limit_seconds + edit_limit_seconds_buffer +
-        now.diffSeconds(message.timestamp * 1000) > 0) && message.sent_by_me) {
+        now.diffSeconds(message.timestamp * 1000) > 0 && message.sent_by_me) {
         return editability_types.FULL;
     }
 

static/js/message_fetch.js

@@ -20,7 +20,7 @@ function process_result(data, opts) {
 
     $('#connection-error').removeClass("show");
 
-    if ((messages.length === 0) && (current_msg_list === message_list.narrowed) &&
+    if (messages.length === 0 && current_msg_list === message_list.narrowed &&
         message_list.narrowed.empty()) {
         // Even after trying to load more messages, we have no
         // messages to display in this narrow.

static/js/message_list.js

@@ -57,15 +57,15 @@ exports.MessageList.prototype = {
             self.append_to_view(bottom_messages, opts);
         }
 
-        if ((self === exports.narrowed) && !self.empty()) {
+        if (self === exports.narrowed && !self.empty()) {
             // If adding some new messages to the message tables caused
             // our current narrow to no longer be empty, hide the empty
             // feed placeholder text.
             narrow.hide_empty_narrow_message();
         }
 
-        if ((self === exports.narrowed) && !self.empty() &&
+        if (self === exports.narrowed && !self.empty() &&
-            (self.selected_id() === -1)) {
+            self.selected_id() === -1) {
             // And also select the newly arrived message.
             self.select_id(self.selected_id(), {then_scroll: true, use_closest: true});
         }
@@ -318,7 +318,7 @@ exports.MessageList.prototype = {
 
     show_message_as_read: function (message, options) {
         var row = this.get_row(message.id);
-        if ((options.from === 'pointer' && feature_flags.mark_read_at_bottom) ||
+        if (options.from === 'pointer' && feature_flags.mark_read_at_bottom ||
             options.from === "server") {
             row.find('.unread_marker').addClass('fast_fade');
         } else {

static/js/message_list_data.js

@@ -193,7 +193,7 @@ MessageListData.prototype = {
 
     update_user_full_name: function (user_id, full_name) {
         _.each(this._items, function (item) {
-            if (item.sender_id && (item.sender_id === user_id)) {
+            if (item.sender_id && item.sender_id === user_id) {
                 item.sender_full_name = full_name;
             }
         });
@@ -205,7 +205,7 @@ MessageListData.prototype = {
         // especially if we want to optimize this with some kind of
         // hash that maps sender_id -> messages.
         _.each(this._items, function (item) {
-            if (item.sender_id && (item.sender_id === user_id)) {
+            if (item.sender_id && item.sender_id === user_id) {
                 item.small_avatar_url = avatar_url;
             }
         });
@@ -213,7 +213,7 @@ MessageListData.prototype = {
 
     update_stream_name: function (stream_id, new_stream_name) {
         _.each(this._items, function (item) {
-            if (item.stream_id && (item.stream_id === stream_id)) {
+            if (item.stream_id && item.stream_id === stream_id) {
                 item.display_recipient = new_stream_name;
                 item.stream = new_stream_name;
             }
@@ -545,8 +545,8 @@ MessageListData.prototype = {
             var prev = self._next_nonlocal_message(self._items, index,
                                                    function (idx) { return idx - 1; });
 
-            if ((next !== undefined && current_message.id > next.id) ||
+            if (next !== undefined && current_message.id > next.id ||
-                (prev !== undefined && current_message.id < prev.id)) {
+                prev !== undefined && current_message.id < prev.id) {
                 blueslip.debug("Changed message ID from server caused out-of-order list, reordering");
                 self._items.sort(message_sort_func);
                 if (self.muting_enabled) {

static/js/message_list_view.js

@@ -18,7 +18,7 @@ function MessageListView(list, table_name, collapse_messages) {
 
 function mention_button_refers_to_me(elem) {
     var user_id = $(elem).attr('data-user-id');
-    if ((user_id === '*') || people.is_my_user_id(user_id)) {
+    if (user_id === '*' || people.is_my_user_id(user_id)) {
         return true;
     }
 
@@ -688,7 +688,7 @@ MessageListView.prototype = {
         var last_visible = rows.last_visible();
 
         // Make sure we have a selected row and last visible row. (defensive)
-        if (!(selected_row && (selected_row.length > 0) && last_visible)) {
+        if (!(selected_row && selected_row.length > 0 && last_visible)) {
             return;
         }
 
@@ -791,10 +791,10 @@ MessageListView.prototype = {
         //   of the bottom of the currently rendered window and the
         //   bottom of the window does not abut the end of the
         //   message list
-        if (!(((selected_idx - this._render_win_start < this._RENDER_THRESHOLD)
+        if (!(selected_idx - this._render_win_start < this._RENDER_THRESHOLD
-                && (this._render_win_start !== 0)) ||
+                && this._render_win_start !== 0 ||
-               ((this._render_win_end - selected_idx <= this._RENDER_THRESHOLD)
+               this._render_win_end - selected_idx <= this._RENDER_THRESHOLD
-                && (this._render_win_end !== this.list.num_items())))) {
+                && this._render_win_end !== this.list.num_items())) {
             return false;
         }
 

static/js/message_viewport.js

@@ -106,10 +106,10 @@ exports.set_message_position = function (message_top, message_height, viewport_i
 function in_viewport_or_tall(rect, top_of_feed, bottom_of_feed,
                              require_fully_visible) {
     if (require_fully_visible) {
-        return (rect.top > top_of_feed) && // Message top is in view and
+        return rect.top > top_of_feed && // Message top is in view and
-                ((rect.bottom < bottom_of_feed) || // message is fully in view or
+                (rect.bottom < bottom_of_feed || // message is fully in view or
-                 ((rect.height > bottom_of_feed - top_of_feed) &&
+                 rect.height > bottom_of_feed - top_of_feed &&
-                  (rect.top < bottom_of_feed))); // message is tall.
+                  rect.top < bottom_of_feed); // message is tall.
     }
     return rect.bottom > top_of_feed && rect.top < bottom_of_feed;
 }
@@ -334,8 +334,8 @@ exports.keep_pointer_in_view = function () {
     }
 
     var info = message_viewport.message_viewport_info();
-    var top_threshold = info.visible_top + (1 / 10 * info.visible_height);
+    var top_threshold = info.visible_top + 1 / 10 * info.visible_height;
-    var bottom_threshold = info.visible_top + (9 / 10 * info.visible_height);
+    var bottom_threshold = info.visible_top + 9 / 10 * info.visible_height;
 
     function message_is_far_enough_down() {
         if (message_viewport.at_top()) {
@@ -365,7 +365,7 @@ exports.keep_pointer_in_view = function () {
 
     function message_is_far_enough_up() {
         return message_viewport.at_bottom() ||
-            (next_row.offset().top <= bottom_threshold);
+            next_row.offset().top <= bottom_threshold;
     }
 
     function adjust(in_view, get_next_row) {

static/js/narrow.js

@@ -411,8 +411,8 @@ exports.update_selection = function (opts) {
     }
 
     var preserve_pre_narrowing_screen_position =
-        (message_list.narrowed.get(msg_id) !== undefined) &&
+        message_list.narrowed.get(msg_id) !== undefined &&
-        (select_offset !== undefined);
+        select_offset !== undefined;
 
     var then_scroll = !preserve_pre_narrowing_screen_position;
 
@@ -620,8 +620,8 @@ exports.deactivate = function () {
 
     if (current_msg_list.selected_id() !== -1) {
         var preserve_pre_narrowing_screen_position =
-            (current_msg_list.selected_row().length > 0) &&
+            current_msg_list.selected_row().length > 0 &&
-            (current_msg_list.pre_narrow_offset !== undefined);
+            current_msg_list.pre_narrow_offset !== undefined;
         var message_id_to_select;
         var select_opts = {
             then_scroll: true,
@@ -711,7 +711,7 @@ function pick_empty_narrow_banner() {
             // You have no unread messages.
             return $("#no_unread_narrow_message");
         }
-    } else if ((first_operator === "stream") && !stream_data.is_subscribed(first_operand)) {
+    } else if (first_operator === "stream" && !stream_data.is_subscribed(first_operand)) {
         // You are narrowed to a stream which does not exist or is a private stream
         // in which you were never subscribed.
         var stream_sub = stream_data.get_sub(narrow_state.stream());

static/js/narrow_state.js

@@ -334,7 +334,7 @@ exports.narrowed_to_topic = function () {
 };
 
 exports.narrowed_to_search = function () {
-    return (current_filter !== undefined) && current_filter.is_search();
+    return current_filter !== undefined && current_filter.is_search();
 };
 
 exports.muting_enabled = function () {

static/js/navigate.js

@@ -122,7 +122,7 @@ exports.page_down = function () {
 
 exports.scroll_to_selected = function () {
     var selected_row = current_msg_list.selected_row();
-    if (selected_row && (selected_row.length !== 0)) {
+    if (selected_row && selected_row.length !== 0) {
         message_viewport.recenter_view(selected_row);
     }
 };

static/js/notifications.js

@@ -393,12 +393,12 @@ exports.message_is_notifiable = function (message) {
 
     // Messages to muted streams that don't mention us specifically
     // are not notifiable.
-    if ((message.type === "stream") &&
+    if (message.type === "stream" &&
         !stream_data.in_home_view(message.stream_id)) {
         return false;
     }
 
-    if ((message.type === "stream") &&
+    if (message.type === "stream" &&
         muting.is_topic_muted(message.stream, message.subject)) {
         return false;
     }
@@ -411,14 +411,14 @@ exports.message_is_notifiable = function (message) {
 function should_send_desktop_notification(message) {
     // For streams, send if desktop notifications are enabled for this
     // stream.
-    if ((message.type === "stream") &&
+    if (message.type === "stream" &&
         stream_data.receives_desktop_notifications(message.stream)) {
         return true;
     }
 
     // For PMs and @-mentions, send if desktop notifications are
     // enabled.
-    if ((message.type === "private") &&
+    if (message.type === "private" &&
         page_params.enable_desktop_notifications) {
         return true;
     }
@@ -440,13 +440,13 @@ function should_send_desktop_notification(message) {
 
 function should_send_audible_notification(message) {
     // For streams, ding if sounds are enabled for this stream.
-    if ((message.type === "stream") &&
+    if (message.type === "stream" &&
         stream_data.receives_audible_notifications(message.stream)) {
         return true;
     }
 
     // For PMs and @-mentions, ding if sounds are enabled.
-    if ((message.type === "private") && page_params.enable_sounds) {
+    if (message.type === "private" && page_params.enable_sounds) {
         return true;
     }
 

static/js/pm_list.js

@@ -96,8 +96,8 @@ exports._build_private_messages_list = function (active_conversation, max_privat
 
         var num_unread = unread.num_unread_for_person(user_ids_string);
 
-        var always_visible = (idx < max_private_messages) || (num_unread > 0)
+        var always_visible = idx < max_private_messages || num_unread > 0
-            || (user_ids_string === active_conversation);
+            || user_ids_string === active_conversation;
 
         if (!always_visible) {
             if (!zoomed_in) {

static/js/popovers.js

@@ -101,9 +101,9 @@ function user_last_seen_time_status(user_id) {
 function calculate_info_popover_placement(size, elt) {
     var ypos = elt.offset().top;
 
-    if (!((ypos + (size / 2) < message_viewport.height()) &&
+    if (!(ypos + size / 2 < message_viewport.height() &&
-          (ypos > (size / 2)))) {
+          ypos > size / 2)) {
-        if ((ypos + size) < message_viewport.height()) {
+        if (ypos + size < message_viewport.height()) {
             return 'bottom';
         } else if (ypos > size) {
             return 'top';
@@ -345,7 +345,7 @@ exports.toggle_actions_popover = function (element, id) {
         var ypos = elt.offset().top;
         elt.popover({
             // Popover height with 7 items in it is ~190 px
-            placement: (message_viewport.height() - ypos) < 220 ? 'top' : 'bottom',
+            placement: message_viewport.height() - ypos < 220 ? 'top' : 'bottom',
             title:     "",
             content:   templates.render('actions_popover_content', args),
             trigger:   "manual",
@@ -368,7 +368,7 @@ exports.render_actions_remind_popover = function (element, id) {
         var ypos = elt.offset().top;
         elt.popover({
             // Popover height with 7 items in it is ~190 px
-            placement: (message_viewport.height() - ypos) < 220 ? 'top' : 'bottom',
+            placement: message_viewport.height() - ypos < 220 ? 'top' : 'bottom',
             title:     "",
             content:   templates.render('remind_me_popover_content', args),
             trigger:   "manual",

static/js/presence.js

@@ -25,7 +25,7 @@ exports.is_active = function (user_id) {
 
     if (presence_info[user_id]) {
         var status = presence_info[user_id].status;
-        if (status && (status === "active")) {
+        if (status && status === "active") {
             return true;
         }
     }

static/js/reactions.js

@@ -33,9 +33,9 @@ exports.open_reactions_popover = function () {
 exports.current_user_has_reacted_to_emoji = function (message, emoji_code, type) {
     var user_id = page_params.user_id;
     return _.any(message.reactions, function (r) {
-        return (r.user.id === user_id) &&
+        return r.user.id === user_id &&
-               (r.reaction_type === type) &&
+               r.reaction_type === type &&
-               (r.emoji_code === emoji_code);
+               r.emoji_code === emoji_code;
     });
 };
 
@@ -206,7 +206,7 @@ exports.add_reaction = function (event) {
     var reacted = exports.current_user_has_reacted_to_emoji(message,
                                                             event.emoji_code,
                                                             event.reaction_type);
-    if (reacted && (event.user.user_id === page_params.user_id)) {
+    if (reacted && event.user.user_id === page_params.user_id) {
         return;
     }
 
@@ -317,7 +317,7 @@ exports.remove_reaction = function (event) {
     var not_reacted = !exports.current_user_has_reacted_to_emoji(message,
                                                                  emoji_code,
                                                                  reaction_type);
-    if (not_reacted && (event.user.user_id === page_params.user_id)) {
+    if (not_reacted && event.user.user_id === page_params.user_id) {
         return;
     }
 

static/js/scroll_bar.js

@@ -37,21 +37,21 @@ $(function () {
     if (sbWidth > 0) {
         $(".header").css("left", "-" + sbWidth + "px");
         $(".header-main").css("left", sbWidth + "px");
-        $(".header-main").css("max-width", (1400 + sbWidth) + "px");
+        $(".header-main").css("max-width", 1400 + sbWidth + "px");
-        $(".header-main .column-middle").css("margin-right", (250 + sbWidth) + "px");
+        $(".header-main .column-middle").css("margin-right", 250 + sbWidth + "px");
 
         $(".fixed-app").css("left", "-" + sbWidth + "px");
-        $(".fixed-app .app-main").css("max-width", (1400 + sbWidth) + "px");
+        $(".fixed-app .app-main").css("max-width", 1400 + sbWidth + "px");
-        $(".fixed-app .column-middle").css("margin-left", (250 + sbWidth) + "px");
+        $(".fixed-app .column-middle").css("margin-left", 250 + sbWidth + "px");
 
         $(".column-right").css("right", sbWidth + "px");
         $(".app-main .right-sidebar").css({"margin-left": sbWidth + "px",
-                                           width: (250 - sbWidth) + "px"});
+                                           width: 250 - sbWidth + "px"});
 
         $("#compose").css("left", "-" + sbWidth + "px");
         $(".compose-content").css({left: sbWidth + "px",
-                                   "margin-right": (250 + sbWidth) + "px"});
+                                   "margin-right": 250 + sbWidth + "px"});
-        $("#compose-container").css("max-width", (1400 + sbWidth) + "px");
+        $("#compose-container").css("max-width", 1400 + sbWidth + "px");
         $('#sidebar-keyboard-shortcuts #keyboard-icon').css({right: sbWidth + 13 + "px"});
 
         $("head").append("<style> @media (max-width: 1025px) { .compose-content, .header-main .column-middle { margin-right: " + (7 + sbWidth) + "px !important; } } " +

static/js/search_suggestion.js

@@ -159,7 +159,7 @@ function get_group_suggestions(all_persons, last, operators) {
         if (_.contains(parts, person.email)) {
             return false;
         }
-        return (last_part === '') || people.person_matches_query(person, last_part);
+        return last_part === '' || people.person_matches_query(person, last_part);
     });
 
     persons.sort(compare_by_huddle(parts));
@@ -264,7 +264,7 @@ function get_topic_suggestions(last, operators) {
 
     var operator = Filter.canonicalize_operator(last.operator);
     var operand = last.operand;
-    var negated = (operator === 'topic') && last.negated;
+    var negated = operator === 'topic' && last.negated;
     var stream;
     var guess;
     var filter = new Filter(operators);
@@ -391,9 +391,9 @@ function get_special_filter_suggestions(last, operators, suggestions) {
         var suggestion_operand = s.search_string.substring(s.search_string.indexOf(":") + 1);
         // e.g for `att` search query, `has:attachment` should be suggested.
         var show_operator_suggestions = last.operator === 'search' && suggestion_operand.toLowerCase().indexOf(last_string) === 0;
-        return (s.search_string.toLowerCase().indexOf(last_string) === 0) ||
+        return s.search_string.toLowerCase().indexOf(last_string) === 0 ||
                show_operator_suggestions ||
-               (s.description.toLowerCase().indexOf(last_string) === 0);
+               s.description.toLowerCase().indexOf(last_string) === 0;
     });
 
     // Only show home if there's an empty bar
@@ -478,7 +478,7 @@ function get_has_filter_suggestions(last, operators) {
 
 function get_sent_by_me_suggestions(last, operators) {
     var last_string = Filter.unparse([last]).toLowerCase();
-    var negated = last.negated || (last.operator === 'search' && last.operand[0] === '-');
+    var negated = last.negated || last.operator === 'search' && last.operand[0] === '-';
     var negated_symbol = negated ? '-' : '';
     var verb = negated ? 'exclude ' : '';
 

static/js/sent_messages.js

@@ -119,8 +119,8 @@ exports.message_state = function (opts) {
     };
 
     self.ready = function () {
-        return (self.data.send_finished !== undefined) &&
+        return self.data.send_finished !== undefined &&
-               (self.data.received !== undefined);
+               self.data.received !== undefined;
     };
 
     return self;

static/js/server_events.js

@@ -112,7 +112,7 @@ function get_events_success(events) {
         home_msg_list.select_id(new_pointer, {then_scroll: true, use_closest: true});
     }
 
-    if ((home_msg_list.selected_id() === -1) && !home_msg_list.empty()) {
+    if (home_msg_list.selected_id() === -1 && !home_msg_list.empty()) {
         home_msg_list.select_id(home_msg_list.first().id, {then_scroll: false});
     }
 
@@ -185,8 +185,8 @@ function get_events(options) {
                 get_events_xhr = undefined;
                 // If we're old enough that our message queue has been
                 // garbage collected, immediately reload.
-                if ((xhr.status === 400) &&
+                if (xhr.status === 400 &&
-                    (JSON.parse(xhr.responseText).code === 'BAD_EVENT_QUEUE_ID')) {
+                    JSON.parse(xhr.responseText).code === 'BAD_EVENT_QUEUE_ID') {
                     page_params.event_queue_expired = true;
                     reload.initiate({immediate: true,
                                      save_pointer: false,
@@ -247,7 +247,7 @@ exports.home_view_loaded = function home_view_loaded() {
 var watchdog_time = $.now();
 exports.check_for_unsuspend = function () {
     var new_time = $.now();
-    if ((new_time - watchdog_time) > 20000) { // 20 seconds.
+    if (new_time - watchdog_time > 20000) { // 20 seconds.
         // Defensively reset watchdog_time here in case there's an
         // exception in one of the event handlers
         watchdog_time = new_time;

static/js/settings_ui.js

@@ -69,10 +69,10 @@ exports.do_settings_change = function (request_method, url, data, status_element
 // * disable_on_uncheck is boolean, true if sub setting should be disabled
 //   when main setting unchecked.
 exports.disable_sub_setting_onchange = function (is_checked, sub_setting_id, disable_on_uncheck) {
-    if ((is_checked && disable_on_uncheck) || (!is_checked && !disable_on_uncheck)) {
+    if (is_checked && disable_on_uncheck || !is_checked && !disable_on_uncheck) {
         $("#" + sub_setting_id).attr("disabled", false);
         $("#" + sub_setting_id + "_label").parent().removeClass("control-label-disabled");
-    } else if ((is_checked && !disable_on_uncheck) || (!is_checked && disable_on_uncheck)) {
+    } else if (is_checked && !disable_on_uncheck || !is_checked && disable_on_uncheck) {
         $("#" + sub_setting_id).attr("disabled", "disabled");
         $("#" + sub_setting_id + "_label").parent().addClass("control-label-disabled");
     }

static/js/settings_user_groups.js

@@ -80,7 +80,7 @@ exports.populate_user_groups = function () {
             var description = $('#user-groups #' + data.id + ' .description').text().trim();
             var name = $('#user-groups #' + data.id + ' .name').text().trim();
 
-            if ((group_data.description === description && group_data.name === name) &&
+            if (group_data.description === description && group_data.name === name &&
                 (!draft_group.length || same_groups)) {
                 return false;
             }

static/js/stats/stats.js

@@ -52,7 +52,7 @@ function format_date(date, include_hour) {
 
         var str = hour >= 12 ? "PM" : "AM";
 
-        return month_str + " " + day + ", " + (hour % 12) + ":00" + str;
+        return month_str + " " + day + ", " + hour % 12 + ":00" + str;
     }
     return month_str + ' ' + day + ', ' + year;
 }

static/js/stream_edit.js

@@ -227,8 +227,8 @@ function show_subscription_settings(sub_row) {
                 return false;
             }
             // Case-insensitive.
-            var item_matches = (item.email.toLowerCase().indexOf(query) !== -1) ||
+            var item_matches = item.email.toLowerCase().indexOf(query) !== -1 ||
-                               (item.full_name.toLowerCase().indexOf(query) !== -1);
+                               item.full_name.toLowerCase().indexOf(query) !== -1;
             var is_subscribed = stream_data.is_user_subscribed(sub.name, item.user_id);
             return item_matches && !is_subscribed;
         },

static/js/stream_popover.js

@@ -79,7 +79,7 @@ function update_spectrum(popover, update_func) {
     var current_top_px = parseFloat(popover_root.css('top').replace('px', ''));
     var height_delta = -(after_height - initial_height) * 0.5;
 
-    popover_root.css('top', (current_top_px + height_delta) + "px");
+    popover_root.css('top', current_top_px + height_delta + "px");
 }
 
 function build_stream_popover(e) {

static/js/subs.js

@@ -158,7 +158,7 @@ exports.rerender_subscribers_count = function (sub, just_subscribed) {
     }
     var stream_row = row_for_stream_id(sub.stream_id);
     stream_data.update_subscribers_count(sub);
-    if (!sub.can_access_subscribers || (just_subscribed && sub.invite_only)) {
+    if (!sub.can_access_subscribers || just_subscribed && sub.invite_only) {
         var rendered_sub_count = templates.render("subscription_count", sub);
         stream_row.find('.subscriber-count').expectOne().html(rendered_sub_count);
     } else {
@@ -331,7 +331,7 @@ function stream_matches_query(query, sub, attr) {
             }
         });
     }());
-    flag = flag && ((sub.subscribed || !query.subscribed_only) ||
+    flag = flag && (sub.subscribed || !query.subscribed_only ||
                     sub.data_temp_view === "true");
     return flag;
 }

static/js/tictactoe_widget.js

@@ -31,8 +31,8 @@ var tictactoe_data_holder = function () {
             }
 
             return (
-                (square_values[line[1]] === token) &&
+                square_values[line[1]] === token &&
-                (square_values[line[2]] === token));
+                square_values[line[2]] === token);
         }
 
         var board = [1, 2, 3, 4, 5, 6, 7, 8, 9];

static/js/timerender.js

@@ -36,7 +36,7 @@ exports.render_now = function (time, today) {
     var days_old = Math.round(start_of_other_day.diffDays(start_of_today));
 
     var is_older_year =
-        (start_of_today.getFullYear() - start_of_other_day.getFullYear()) > 0;
+        start_of_today.getFullYear() - start_of_other_day.getFullYear() > 0;
 
     if (days_old === 0) {
         time_str = i18n.t("Today");
@@ -250,7 +250,7 @@ exports.absolute_time = (function () {
             today = new Date();
         }
         var date = new Date(timestamp);
-        var is_older_year = (today.getFullYear() - date.getFullYear()) > 0;
+        var is_older_year = today.getFullYear() - date.getFullYear() > 0;
         var H_24 = page_params.twenty_four_hour_time;
         var str = MONTHS[date.getMonth()] + " " + date.getDate();
         // include year if message date is from a previous year

static/js/top_left_corner.js

@@ -67,7 +67,7 @@ exports.handle_narrow_activated = function (filter) {
     ops = filter.operands('is');
     if (ops.length >= 1) {
         filter_name = ops[0];
-        if ((filter_name === 'starred') || (filter_name === 'mentioned')) {
+        if (filter_name === 'starred' || filter_name === 'mentioned') {
             filter_li = exports.get_global_filter_li(filter_name);
             filter_li.addClass('active-filter');
         }
@@ -75,7 +75,7 @@ exports.handle_narrow_activated = function (filter) {
 
     var op_is = filter.operands('is');
     var op_pm = filter.operands('pm-with');
-    if (((op_is.length >= 1) && _.contains(op_is, "private")) || op_pm.length >= 1) {
+    if (op_is.length >= 1 && _.contains(op_is, "private") || op_pm.length >= 1) {
         if (!people.is_valid_bulk_emails_for_compose(op_pm)) {
             // Don't go into the else statement and close the pm_list.
             return;

static/js/topic_list.js

@@ -74,8 +74,8 @@ exports.widget = function (parent_elem, my_stream_id) {
 
             if (!zoomed) {
                 // Show the most recent topics, as well as any with unread messages
-                var show_topic = (idx < max_topics) || (num_unread > 0) ||
+                var show_topic = idx < max_topics || num_unread > 0 ||
-                                 (self.active_topic === topic_name.toLowerCase());
+                                 self.active_topic === topic_name.toLowerCase();
 
                 if (!show_topic) {
                     return;
@@ -236,7 +236,7 @@ exports.zoom_in = function () {
     var before_count = active_widget.num_items();
 
     function on_success() {
-        if (!active_widget || (stream_id !== active_widget.get_stream_id())) {
+        if (!active_widget || stream_id !== active_widget.get_stream_id()) {
             blueslip.warn('User re-narrowed before topic history was returned.');
             return;
         }

static/js/ui_init.js

@@ -40,7 +40,7 @@ function message_hover(message_row) {
     }
 
     // But the message edit hover icon is determined by whether the message is still editable
-    if ((message_edit.get_editability(message) === message_edit.editability_types.FULL) &&
+    if (message_edit.get_editability(message) === message_edit.editability_types.FULL &&
         !message.status_message) {
         message_row.find(".edit_content").html('<i class="fa fa-pencil edit_content_button" aria-hidden="true" title="Edit"></i>');
     } else {
@@ -100,8 +100,8 @@ function initialize_kitchen_sink_stuff() {
         var max_scroll = this.scrollHeight - self.innerHeight() - 1;
 
         e.stopPropagation();
-        if (((delta < 0) && (scroll <= 0)) ||
+        if (delta < 0 && scroll <= 0 ||
-            ((delta > 0) && (scroll >= max_scroll))) {
+            delta > 0 && scroll >= max_scroll) {
             e.preventDefault();
         }
     });

static/js/unread_ui.js

@@ -38,7 +38,7 @@ exports.set_count_toggle_button = function (elem, count) {
             return elem.stop(true, true).hide();
         }
         return elem.hide(500);
-    } else if ((count > 0) && (count < 1000)) {
+    } else if (count > 0 && count < 1000) {
         elem.show(500);
         return elem.text(count);
     }
@@ -87,8 +87,8 @@ function consider_bankruptcy() {
     }
 
     var now = new XDate(true).getTime() / 1000;
-    if ((page_params.unread_msgs.count > 500) &&
+    if (page_params.unread_msgs.count > 500 &&
-            (now - page_params.furthest_read_time > 60 * 60 * 24 * 2)) { // 2 days.
+            now - page_params.furthest_read_time > 60 * 60 * 24 * 2) { // 2 days.
         var rendered_modal = templates.render('bankruptcy_modal', {
             unread_count: page_params.unread_msgs.count});
         $('#bankruptcy-unread-count').html(rendered_modal);

static/js/util.js

@@ -58,8 +58,8 @@ exports.lower_bound = function (array, arg1, arg2, arg3, arg4) {
 
 exports.same_stream_and_topic = function util_same_stream_and_topic(a, b) {
     // Streams and topics are case-insensitive.
-    return (a.stream_id === b.stream_id) &&
+    return a.stream_id === b.stream_id &&
-            (a.subject.toLowerCase() === b.subject.toLowerCase());
+            a.subject.toLowerCase() === b.subject.toLowerCase();
 };
 
 exports.is_pm_recipient = function (email, message) {
@@ -74,7 +74,7 @@ exports.extract_pm_recipients = function (recipients) {
 };
 
 exports.same_recipient = function util_same_recipient(a, b) {
-    if ((a === undefined) || (b === undefined)) {
+    if (a === undefined || b === undefined) {
         return false;
     }
     if (a.type !== b.type) {
@@ -96,8 +96,8 @@ exports.same_recipient = function util_same_recipient(a, b) {
 };
 
 exports.same_sender = function util_same_sender(a, b) {
-    return (a !== undefined) && (b !== undefined) &&
+    return a !== undefined && b !== undefined &&
-            (a.sender_email.toLowerCase() === b.sender_email.toLowerCase());
+            a.sender_email.toLowerCase() === b.sender_email.toLowerCase();
 };
 
 exports.normalize_recipients = function (recipients) {