From f4db89c7e90bd410104b7186aa87575ef2c8a148 Mon Sep 17 00:00:00 2001
From: Steve Howell <steve@zulip.com>
Date: Tue, 11 Feb 2014 14:45:54 -0500
Subject: [PATCH] Supported negated terms in filter predicates (JS).

(imported from commit b50527620b5b451b4d6e0dc073de4036fe2b7e1f)
---
 static/js/filter.js                  |  8 +++++++-
 zerver/tests/frontend/node/filter.js | 11 +++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/static/js/filter.js b/static/js/filter.js
index f8bbb7a397..80c924d3fa 100644
--- a/static/js/filter.js
+++ b/static/js/filter.js
@@ -131,6 +131,7 @@ Filter.canonicalize_operator = function (operator) {
 };
 
 Filter.canonicalize_term = function (opts) {
+    var negated = opts.negated;
     var operator = opts.operator;
     var operand = opts.operand;
 
@@ -169,6 +170,7 @@ Filter.canonicalize_term = function (opts) {
 
     // We may want to consider allowing mixed-case operators at some point
     return {
+        negated: negated,
         operator: operator,
         operand: operand
     };
@@ -327,7 +329,11 @@ Filter.prototype = {
 
         return function (message) {
             return _.all(operators, function (term) {
-                return message_matches_search_term(message, term.operator, term.operand);
+                var ok = message_matches_search_term(message, term.operator, term.operand);
+                if (term.negated) {
+                    ok = !ok;
+                }
+                return ok;
             });
         };
     }
diff --git a/zerver/tests/frontend/node/filter.js b/zerver/tests/frontend/node/filter.js
index 04eda182ad..d7aad0b5d8 100644
--- a/zerver/tests/frontend/node/filter.js
+++ b/zerver/tests/frontend/node/filter.js
@@ -184,6 +184,17 @@ function get_predicate(operators) {
     assert(!predicate({type: 'private', reply_to: 'steve@foo.com'}));
 }());
 
+(function test_negated_predicates() {
+    var predicate;
+    var narrow;
+
+    narrow = [
+        {operator: 'stream', operand: 'social', negated: true}
+    ];
+    predicate = new Filter(narrow).predicate();
+    assert(predicate({type: 'stream', stream: 'devel'}));
+    assert(!predicate({type: 'stream', stream: 'social'}));
+}());
 
 (function test_mit_exceptions() {
     global.page_params.domain = 'mit.edu';