js: Convert vars declared separately and assigned once to const.

Because of the separate declarations, ESLint would convert them to
`let` and then trigger the `prefer-const` error.

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

frontend_tests/node_tests/hashchange.js

@@ -77,11 +77,8 @@ run_test('operators_round_trip', () => {
 });
 
 run_test('operators_trailing_slash', () => {
-    var hash;
+    const hash = '#narrow/stream/devel/topic/algol/';
-    var narrow;
+    const narrow = hash_util.parse_narrow(hash.split('/'));
-
-    hash = '#narrow/stream/devel/topic/algol/';
-    narrow = hash_util.parse_narrow(hash.split('/'));
     assert.deepEqual(narrow, [
         {operator: 'stream', operand: 'devel', negated: false},
         {operator: 'topic', operand: 'algol', negated: false},
@@ -91,7 +88,6 @@ run_test('operators_trailing_slash', () => {
 run_test('people_slugs', () => {
     var operators;
     var hash;
-    var narrow;
 
     var alice = {
         email: 'alice@example.com',
@@ -105,7 +101,7 @@ run_test('people_slugs', () => {
     ];
     hash = hash_util.operators_to_hash(operators);
     assert.equal(hash, '#narrow/sender/42-alice');
-    narrow = hash_util.parse_narrow(hash.split('/'));
+    const narrow = hash_util.parse_narrow(hash.split('/'));
     assert.deepEqual(narrow, [
         {operator: 'sender', operand: 'alice@example.com', negated: false},
     ]);

frontend_tests/zjsunit/zjquery.js

@@ -74,7 +74,6 @@ exports.make_event_store = (selector) => {
             //    (event_name, handler) or
             //    (event_name, sel, handler)
             var event_name = arguments[0];
-            var sel;
             var handler;
 
             if (arguments.length === 2) {
@@ -93,7 +92,7 @@ exports.make_event_store = (selector) => {
                 throw Error('wrong number of arguments passed in');
             }
 
-            sel = arguments[1];
+            const sel = arguments[1];
             handler = arguments[2];
             assert.equal(typeof sel, 'string', 'String selectors expected here.');
             assert.equal(typeof handler, 'function', 'An handler function expected here.');

static/js/compose_actions.js

@@ -273,13 +273,12 @@ exports.cancel = function () {
 };
 
 exports.respond_to_message = function (opts) {
-    var message;
     var msg_type;
     // Before initiating a reply to a message, if there's an
     // in-progress composition, snapshot it.
     drafts.update_draft();
 
-    message = current_msg_list.selected_message();
+    const message = current_msg_list.selected_message();
 
     if (message === undefined) { // empty narrow implementation
         if (!narrow_state.narrowed_by_pm_reply() &&

static/js/compose_pm_pill.js

@@ -1,8 +1,7 @@
 exports.initialize_pill = function () {
-    var pill;
     var container = $("#private_message_recipient").parent();
 
-    pill = input_pill.create({
+    const pill = input_pill.create({
         container: container,
         create_item_from_text: user_pill.create_item_from_email,
         get_text_from_item: user_pill.get_email_from_item,

static/js/filter.js

@@ -261,9 +261,8 @@ Filter.parse = function (str) {
         return operators;
     }
     _.each(matches, function (token) {
-        var parts;
         var operator;
-        parts = token.split(':');
+        const parts = token.split(':');
         if (token[0] === '"' || parts.length === 1) {
             // Looks like a normal search term.
             search_term.push(token);
@@ -607,15 +606,13 @@ Filter.sorted_term_types = function (term_types) {
 };
 
 Filter.operator_to_prefix = function (operator, negated) {
-    var verb;
-
     operator = Filter.canonicalize_operator(operator);
 
     if (operator === 'search') {
         return negated ? 'exclude' : 'search for';
     }
 
-    verb = negated ? 'exclude ' : '';
+    const verb = negated ? 'exclude ' : '';
 
     switch (operator) {
     case 'stream':

static/js/message_list_view.js

@@ -649,7 +649,6 @@ MessageListView.prototype = {
         var table_name = self.table_name;
         var table = rows.get_table(table_name);
         var orig_scrolltop_offset;
-        var message_containers;
 
         // If we start with the message feed scrolled up (i.e.
         // the bottom message is not visible), then we will respect
@@ -661,7 +660,7 @@ MessageListView.prototype = {
         // all messages lists. To prevent having both list views overwriting
         // each others data we will make a new message object to add data to
         // for rendering.
-        message_containers = _.map(messages, function (message) {
+        const message_containers = _.map(messages, function (message) {
             if (message.starred) {
                 message.starred_status = i18n.t("Unstar");
             } else {

static/js/reload.js

@@ -252,7 +252,6 @@ exports.initiate = function (options) {
     var unconditional_timeout = 1000 * 60 * 30 + util.random_int(0, 1000 * 60 * 5);
     var composing_timeout     = 1000 * 60 * 5  + util.random_int(0, 1000 * 60);
     var home_timeout          = 1000 * 60    + util.random_int(0, 1000 * 60);
-    var compose_done_handler;
     var compose_started_handler;
 
     function reload_from_idle() {
@@ -266,7 +265,7 @@ exports.initiate = function (options) {
     // Make sure we always do a reload eventually
     setTimeout(reload_from_idle, unconditional_timeout);
 
-    compose_done_handler = function () {
+    const compose_done_handler = function () {
         idle_control.cancel();
         idle_control = $(document).idle({idle: home_timeout,
                                          onIdle: reload_from_idle});

static/js/resize.js

@@ -201,7 +201,6 @@ exports.resize_stream_filters_container = function (h) {
 };
 
 exports.resize_page_components = function () {
-    var h;
     var sidebar;
 
     if (page_params.left_side_userlist) {
@@ -232,7 +231,7 @@ exports.resize_page_components = function () {
         }
     }
 
-    h = narrow_window ? left_userlist_get_new_heights() : get_new_heights();
+    const h = narrow_window ? left_userlist_get_new_heights() : get_new_heights();
 
     exports.resize_bottom_whitespace(h);
     $("#buddy_list_wrapper").css('max-height', h.buddy_list_wrapper_max_height);

static/js/search_suggestion.js

@@ -121,8 +121,6 @@ function get_group_suggestions(all_persons, last, operators) {
     //
     // We only generate group suggestions when there's more than one part, and
     // we only use the last part to generate suggestions.
-    var all_but_last_part;
-    var last_part;
 
     var last_comma_index = operand.lastIndexOf(',');
     if (last_comma_index < 0) {
@@ -130,8 +128,8 @@ function get_group_suggestions(all_persons, last, operators) {
     }
 
     // Neither all_but_last_part nor last_part include the final comma.
-    all_but_last_part = operand.slice(0, last_comma_index);
+    const all_but_last_part = operand.slice(0, last_comma_index);
-    last_part = operand.slice(last_comma_index + 1);
+    const last_part = operand.slice(last_comma_index + 1);
 
     // We don't suggest a person if their email is already present in the
     // operand (not including the last part).
@@ -565,7 +563,6 @@ exports.get_suggestions = function (base_query, query) {
     // with information for subsequent callbacks.
     var result = [];
     var suggestion;
-    var base; //base, default suggestion
     var suggestions;
 
     // base_query_operators correspond to the existing pills. query_operators correspond
@@ -632,7 +629,7 @@ exports.get_suggestions = function (base_query, query) {
         base_operators = operators.slice(0, -1);
     }
 
-    base = get_default_suggestion(query_operators.slice(0, -1));
+    const base = get_default_suggestion(query_operators.slice(0, -1));
 
     // Get all individual suggestions, and then attach_suggestions
     // mutates the list 'result' to add a properly-formatted suggestion
@@ -708,7 +705,6 @@ exports.get_suggestions_legacy = function (query) {
     // with information for subsequent callbacks.
     var result = [];
     var suggestion;
-    var base; //base, default suggestion
     var suggestions;
 
     // Add an entry for narrow by operators.
@@ -755,7 +751,7 @@ exports.get_suggestions_legacy = function (query) {
     if (operators.length > 1) {
         base_operators = operators.slice(0, -1);
     }
-    base = get_default_suggestion_legacy(base_operators);
+    const base = get_default_suggestion_legacy(base_operators);
 
     // Get all individual suggestions, and then attach_suggestions
     // mutates the list 'result' to add a properly-formatted suggestion

static/js/settings_bots.js

@@ -115,14 +115,13 @@ exports.render_bots = function () {
 
 exports.generate_zuliprc_uri = function (bot_id) {
     var bot = bot_data.get(bot_id);
-    var data;
     var token;
     // For outgoing webhooks, include the token in the zuliprc.
     // It's needed for authenticating to the Botserver.
     if (bot.bot_type === 3) {
         token = bot_data.get_services(bot_id)[0].token;
     }
-    data = exports.generate_zuliprc_content(bot.email, bot.api_key, token);
+    const data = exports.generate_zuliprc_content(bot.email, bot.api_key, token);
     return exports.encode_zuliprc_as_uri(data);
 };
 

static/js/stream_color.js

@@ -127,7 +127,6 @@ exports.initialize = function () {
 exports.get_color_class = _.memoize(function (color) {
     var match;
     var i;
-    var lightness;
     var channel = [0, 0, 0];
     var mult = 1;
 
@@ -151,7 +150,7 @@ exports.get_color_class = _.memoize(function (color) {
     }
 
     // Compute perceived lightness as CIE L*.
-    lightness = colorspace.luminance_to_lightness(
+    const lightness = colorspace.luminance_to_lightness(
         colorspace.rgb_luminance(channel));
 
     // Determine if we're past the midpoint between the

static/js/ui_init.js

@@ -16,8 +16,6 @@ function message_unhover() {
 }
 
 function message_hover(message_row) {
-    var message;
-
     var id = parseInt(message_row.attr("zid"), 10);
     if (current_message_hover && message_row && current_message_hover.attr("zid") === message_row.attr("zid")) {
         return;
@@ -26,7 +24,7 @@ function message_hover(message_row) {
     if (message_row.hasClass('local')) {
         return;
     }
-    message = current_msg_list.get(rows.id(message_row));
+    const message = current_msg_list.get(rows.id(message_row));
     message_unhover();
     current_message_hover = message_row;