js: Convert _.extend to spread syntax or Object.assign.

This is not always a behavior-preserving translation: _.extend mutates
its first argument.  However, the code does not always appear to have
been written to expect that.

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

frontend_tests/node_tests/stream_list.js

@@ -714,9 +714,10 @@ run_test('refresh_pin', () => {
 
     stream_data.add_sub(sub);
 
-    const pinned_sub = _.extend(sub, {
+    const pinned_sub = {
+        ...sub,
         pin_to_top: true,
-    });
+    };
 
     const li_stub = $.create('li stub');
     li_stub.length = 0;

frontend_tests/zjsunit/namespace.js

@@ -31,7 +31,7 @@ exports.restore = function () {
     requires.forEach(function (fn) {
         delete require.cache[require.resolve(fn)];
     });
-    _.extend(global, old_globals);
+    Object.assign(global, old_globals);
     old_globals = {};
     for (const name of new_globals) {
         delete global[name];

static/js/admin.js

@@ -84,7 +84,7 @@ exports.build_page = function () {
     options.msg_delete_limit_dropdown_values = settings_config.msg_delete_limit_dropdown_values;
     options.bot_creation_policy_values = settings_bots.bot_creation_policy_values;
     options.email_address_visibility_values = settings_config.email_address_visibility_values;
-    _.extend(options, settings_org.get_organization_settings_options());
+    Object.assign(options, settings_org.get_organization_settings_options());
 
     if (options.realm_logo_source !== 'D' && options.realm_night_logo_source === 'D') {
         // If no night mode logo is specified but a day mode one is,

static/js/blueslip.js

@@ -80,7 +80,7 @@ const reported_errors = new Set();
 const last_report_attempt = new Map();
 
 function report_error(msg, stack, opts) {
-    opts = _.extend({show_ui_msg: false}, opts);
+    opts = { show_ui_msg: false, ...opts };
 
     if (stack === undefined) {
         stack = 'No stacktrace available';

static/js/bot_data.js

@@ -45,13 +45,13 @@ exports.del = function bot_data__del(bot_id) {
 
 exports.update = function bot_data__update(bot_id, bot_update) {
     const bot = bots.get(bot_id);
-    _.extend(bot, _.pick(bot_update, bot_fields));
+    Object.assign(bot, _.pick(bot_update, bot_fields));
     set_can_admin(bot);
 
     // We currently only support one service per bot.
     const service = services.get(bot_id)[0];
     if (typeof bot_update.services !== 'undefined' && bot_update.services.length > 0) {
-        _.extend(service, _.pick(bot_update.services[0], services_fields));
+        Object.assign(service, _.pick(bot_update.services[0], services_fields));
     }
     send_change_event();
 };

static/js/channel.js

@@ -83,23 +83,23 @@ function call(args, idempotent) {
 }
 
 exports.get = function (options) {
-    const args = _.extend({type: "GET", dataType: "json"}, options);
+    const args = { type: "GET", dataType: "json", ...options };
     return call(args, options.idempotent);
 };
 
 exports.post = function (options) {
-    const args = _.extend({type: "POST", dataType: "json"}, options);
+    const args = { type: "POST", dataType: "json", ...options };
     return call(args, options.idempotent);
 };
 
 exports.put = function (options) {
-    const args = _.extend({type: "PUT", dataType: "json"}, options);
+    const args = { type: "PUT", dataType: "json", ...options };
     return call(args, options.idempotent);
 };
 
 // Not called exports.delete because delete is a reserved word in JS
 exports.del = function (options) {
-    const args = _.extend({type: "DELETE", dataType: "json"}, options);
+    const args = { type: "DELETE", dataType: "json", ...options };
     return call(args, options.idempotent);
 };
 
@@ -111,7 +111,7 @@ exports.patch = function (options) {
         // method this way
         options.data.append("method", "PATCH");
     } else {
-        options.data = _.extend({}, options.data, {method: 'PATCH'});
+        options.data = { ...options.data, method: 'PATCH' };
     }
     return exports.post(options, options.idempotent);
 };

static/js/compose_actions.js

@@ -169,19 +169,18 @@ exports.maybe_scroll_up_selected_message = function () {
 };
 
 function fill_in_opts_from_current_narrowed_view(msg_type, opts) {
-    let default_opts = {
+    return {
         message_type: msg_type,
         stream: '',
         topic: '',
         private_message_recipient: '',
         trigger: 'unknown',
-    };
 
-    // Set default parameters based on the current narrowed view.
-    const compose_opts = narrow_state.set_compose_defaults();
-    default_opts = _.extend(default_opts, compose_opts);
-    opts = _.extend(default_opts, opts);
-    return opts;
+        // Set default parameters based on the current narrowed view.
+        ...narrow_state.set_compose_defaults(),
+
+        ...opts,
+    };
 }
 
 function same_recipient_as_before(msg_type, opts) {

static/js/emoji_picker.js

@@ -213,7 +213,7 @@ function filter_emojis() {
                 for (const alias of emoji_dict.aliases) {
                     const match = search_terms.every(search_term => alias.includes(search_term));
                     if (match) {
-                        search_results.push(_.extend({}, emoji_dict, {name: alias}));
+                        search_results.push({ ...emoji_dict, name: alias });
                         break;  // We only need the first matching alias per emoji.
                     }
                 }
@@ -313,9 +313,10 @@ function update_emoji_showcase($focused_emoji) {
     const canonical_name = emoji.get_canonical_name(focused_emoji_name);
     const focused_emoji_dict = emoji.emojis_by_name.get(canonical_name);
 
-    const emoji_dict = _.extend({}, focused_emoji_dict, {
+    const emoji_dict = {
+        ...focused_emoji_dict,
         name: focused_emoji_name.replace(/_/g, ' '),
-    });
+    };
     const rendered_showcase = render_emoji_showcase({
         emoji_dict: emoji_dict,
     });

static/js/message_list.js

@@ -19,9 +19,7 @@ exports.MessageList = function (opts) {
         });
     }
 
-    _.extend(opts, {
-        collapse_messages: true,
-    });
+    opts.collapse_messages = true;
 
     const collapse_messages = opts.collapse_messages;
     const table_name = opts.table_name;
@@ -125,7 +123,7 @@ exports.MessageList.prototype = {
     },
 
     clear: function  MessageList_clear(opts) {
-        opts = _.extend({clear_selected_id: true}, opts);
+        opts = { clear_selected_id: true, ...opts };
 
         this.data.clear();
         this.view.clear_rendering_state(true);
@@ -140,18 +138,18 @@ exports.MessageList.prototype = {
     },
 
     select_id: function MessageList_select_id(id, opts) {
-        opts = _.extend({
+        opts = {
             then_scroll: false,
             target_scroll_offset: undefined,
             use_closest: false,
             empty_ok: false,
             mark_read: true,
             force_rerender: false,
-        }, opts, {
+            ...opts,
             id: id,
             msg_list: this,
             previously_selected: this.data.selected_id(),
-        });
+        };
 
         function convert_id(str_id) {
             const id = parseFloat(str_id);
@@ -293,7 +291,7 @@ exports.MessageList.prototype = {
     },
 
     append_to_view: function (messages, opts) {
-        opts = _.extend({messages_are_new: false}, opts);
+        opts = { messages_are_new: false, ...opts };
 
         this.num_appends += 1;
         const render_info = this.view.append(messages, opts.messages_are_new);

static/js/message_list_view.js

@@ -640,9 +640,10 @@ MessageListView.prototype = {
     _get_message_template: function (message_container) {
         const msg_reactions = reactions.get_message_reactions(message_container.msg);
         message_container.msg.message_reactions = msg_reactions;
-        const msg_to_render = _.extend(message_container, {
+        const msg_to_render = {
+            ...message_container,
             table_name: this.table_name,
-        });
+        };
         return render_single_message(msg_to_render);
     },
 

static/js/server_events.js

@@ -166,7 +166,7 @@ function hide_ui_connection_error() {
 }
 
 function get_events(options) {
-    options = _.extend({dont_block: false}, options);
+    options = { dont_block: false, ...options };
 
     if (reload_state.is_in_progress()) {
         return;

static/js/settings_org.js

@@ -38,9 +38,10 @@ exports.maybe_disable_widgets = function () {
 };
 
 exports.get_sorted_options_list = function (option_values_object) {
-    const options_list = Object.keys(option_values_object).map((key) => {
-        return _.extend(option_values_object[key], {key: key});
-    });
+    const options_list = Object.keys(option_values_object).map(key => ({
+        ...option_values_object[key],
+        key: key,
+    }));
     let comparator = (x, y) => x.order - y.order;
     if (!options_list[0].order) {
         comparator = (x, y) => {
@@ -810,8 +811,10 @@ exports.build_page = function () {
         const subsection = subsection_id.split('-').join('_');
         const subsection_elem = save_button.closest('.org-subsection-parent');
 
-        let data = populate_data_for_request(subsection_elem);
-        data = _.extend(data, get_complete_data_for_subsection(subsection));
+        const data = {
+            ...populate_data_for_request(subsection_elem),
+            ...get_complete_data_for_subsection(subsection),
+        };
         exports.save_organization_settings(data, save_button);
     });
 

static/js/stream_color.js

@@ -51,9 +51,11 @@ const subscriptions_table_colorpicker_options = {
 };
 
 exports.set_colorpicker_color = function (colorpicker, color) {
-    colorpicker.spectrum(_.extend(subscriptions_table_colorpicker_options,
-                                  {color: color,
-                                   container: "#subscription_overlay .subscription_settings.show"}));
+    colorpicker.spectrum({
+        ...subscriptions_table_colorpicker_options,
+        color: color,
+        container: "#subscription_overlay .subscription_settings.show",
+    });
 };
 
 exports.update_stream_color = function (sub, color, opts) {

static/js/util.js

@@ -175,7 +175,7 @@ exports.array_compare = function util_array_compare(a, b) {
 const unassigned_value_sentinel = {};
 exports.CachedValue = function (opts) {
     this._value = unassigned_value_sentinel;
-    _.extend(this, opts);
+    Object.assign(this, opts);
 };
 
 exports.CachedValue.prototype = {