Attach Filters to MessageLists

This should allow us to stop special-casing the narrowed message list
as much.

(imported from commit 1eb7216fbd8aa16b796c239a189d6ce0008344f9)

zephyr/static/js/message_list.js

@@ -1,9 +1,10 @@
 /*jslint nomen: true */
-function MessageList(table_name, opts) {
+function MessageList(table_name, filter, opts) {
     $.extend(this, {collapse_messages: true}, opts);
     this._items = [];
     this._hash = {};
     this.table_name = table_name;
+    this.filter = filter;
     this._selected_id = -1;
     this._message_groups = [];
     // Half-open interval of the indices that define the current render window
@@ -13,6 +14,9 @@ function MessageList(table_name, opts) {
     if (this.table_name) {
         this._clear_table();
     }
+    if (this.filter === undefined) {
+        this.filter = new narrow.Filter();
+    }
     this.narrowed = false;
     if (this.table_name === "zfilt") {
         this.narrowed = true;

zephyr/static/js/narrow.js

@@ -3,7 +3,11 @@ var narrow = (function () {
 var exports = {};
 
 function Filter(operators) {
-    this._operators = this._canonicalize_operators(operators);
+    if (operators === undefined) {
+        this._operators = [];
+    } else {
+        this._operators = this._canonicalize_operators(operators);
+    }
 }
 
 Filter.prototype = {
@@ -56,6 +60,10 @@ Filter.prototype = {
     _build_predicate: function Filter__build_predicate() {
         var operators = this._operators;
 
+        if (! this.can_apply_locally()) {
+            return function () { return true; };
+        }
+
         // FIXME: This is probably pretty slow.
         // We could turn it into something more like a compiler:
         // build JavaScript code in a string and then eval() it.
@@ -117,6 +125,8 @@ Filter.prototype = {
     }
 };
 
+exports.Filter = Filter;
+
 var current_filter;
 
 exports.active = function () {
@@ -353,7 +363,8 @@ exports.activate = function (operators, opts) {
         }
     });
 
-    narrowed_msg_list = new MessageList('zfilt', {collapse_messages: collapse_messages});
+    narrowed_msg_list = new MessageList('zfilt', current_filter,
+                                        {collapse_messages: collapse_messages});
     current_msg_list = narrowed_msg_list;
 
     function maybe_select_closest() {

zephyr/static/js/zephyr.js

@@ -1,5 +1,5 @@
 var all_msg_list = new MessageList();
-var home_msg_list = new MessageList('zhome');
+var home_msg_list = new MessageList('zhome', new narrow.Filter([["in", "home"]]));
 var narrowed_msg_list;
 var current_msg_list = home_msg_list;
 var subject_dict = {};