refactor: Add util.sorted_ids().

We borrowed this from typing_data.js and gave it a slightly
different name (sorted -> sorted_ids).

frontend_tests/node_tests/typing_data.js

@@ -1,3 +1,4 @@
+zrequire("util");
 zrequire("typing_data");
 
 (function test_basics() {

static/js/typing_data.js

@@ -10,20 +10,8 @@ function to_int(s) {
     return parseInt(s, 10);
 }
 
-function sorted(user_ids) {
-    // This mapping makes sure we are using ints, and
-    // it also makes sure we don't mutate the list.
-    var id_list = _.map(user_ids, to_int);
-    id_list.sort(function (a, b) {
-        return a - b;
-    });
-    id_list = _.uniq(id_list, true);
-
-    return id_list;
-}
-
 function get_key(group) {
-    var ids = sorted(group);
+    var ids = util.sorted_ids(group);
     return ids.join(',');
 }
 
@@ -34,7 +22,7 @@ exports.add_typist = function (group, typist) {
     if (!_.contains(current, typist)) {
         current.push(typist);
     }
-    typist_dct.set(key, sorted(current));
+    typist_dct.set(key, util.sorted_ids(current));
 };
 
 exports.remove_typist = function (group, typist) {
@@ -61,7 +49,7 @@ exports.get_group_typists = function (group) {
 
 exports.get_all_typists = function () {
     var typists = _.flatten(typist_dct.values(), true);
-    typists = sorted(typists);
+    typists = util.sorted_ids(typists);
     typists = _.uniq(typists, true);
     return typists;
 };

static/js/util.js

@@ -270,6 +270,22 @@ exports.emoji_prefix_sort = function (query, objs, get_item) {
     return { matches: popular_emoji_matches.concat(other_emoji_matches), rest: prefix_sort.rest };
 };
 
+function to_int(s) {
+    return parseInt(s, 10);
+}
+
+exports.sorted_ids = function (ids) {
+    // This mapping makes sure we are using ints, and
+    // it also makes sure we don't mutate the list.
+    var id_list = _.map(ids, to_int);
+    id_list.sort(function (a, b) {
+        return a - b;
+    });
+    id_list = _.uniq(id_list, true);
+
+    return id_list;
+};
+
 return exports;
 
 }());