diff --git a/tools/test-js-with-node b/tools/test-js-with-node
index b9d86df06b..5f4a14bf96 100755
--- a/tools/test-js-with-node
+++ b/tools/test-js-with-node
@@ -8,6 +8,7 @@ export NODE_PATH=$STATIC_DIR
 
 NODEJS=$(which nodejs || which node)
 
+$NODEJS util.js
 $NODEJS message_list.js
 $NODEJS message_tour.js
 $NODEJS unread.js
diff --git a/zerver/tests/frontend/node/util.js b/zerver/tests/frontend/node/util.js
new file mode 100644
index 0000000000..62c3cae12f
--- /dev/null
+++ b/zerver/tests/frontend/node/util.js
@@ -0,0 +1,99 @@
+var assert = require('assert');
+
+(function set_up_dependencies () {
+    global._ = require('third/underscore/underscore.js');
+    global.util = require('js/util.js');
+    global.$ = {};
+}());
+
+var util = global.util;
+
+(function test_CachedValue() {
+    var x = 5;
+
+    var cv = new util.CachedValue({
+        compute_value: function () {
+            return x * 2;
+        }
+    });
+
+    assert.equal(cv.get(), 10);
+
+    x = 6;
+    assert.equal(cv.get(), 10);
+    cv.reset();
+    assert.equal(cv.get(), 12);
+
+}());
+
+(function test_lower_bound() {
+    var arr = [10, 20, 30, 40, 50];
+    assert.equal(util.lower_bound(arr, 5), 0);
+    assert.equal(util.lower_bound(arr, 10), 0);
+    assert.equal(util.lower_bound(arr, 15), 1);
+    assert.equal(util.lower_bound(arr, 50), 4);
+    assert.equal(util.lower_bound(arr, 55), 5);
+    assert.equal(util.lower_bound(arr, 2, 4, 31), 3);
+
+    arr = [{x: 10}, {x: 20}, {x:30}];
+
+    function compare (a, b) {
+        return a.x < b;
+    }
+
+    assert.equal(util.lower_bound(arr, 5, compare), 0);
+    assert.equal(util.lower_bound(arr, 10, compare), 0);
+    assert.equal(util.lower_bound(arr, 15, compare), 1);
+
+}());
+
+(function test_same_recipient() {
+    assert(util.same_recipient(
+        {type: 'stream', stream: 'Foo', subject: 'Bar'},
+        {type: 'stream', stream: 'fOO', subject: 'bar'}
+    ));
+
+    assert(!util.same_recipient(
+        {type: 'stream', stream: 'Foo', subject: 'Bar'},
+        {type: 'stream', stream: 'yo', subject: 'whatever'}
+    ));
+
+    assert(util.same_recipient(
+        {type: 'private', reply_to: 'fred@zulip.com,melissa@zulip.com'},
+        {type: 'private', reply_to: 'fred@zulip.com,melissa@zulip.com'}
+    ));
+
+    assert(!util.same_recipient(
+        {type: 'private', reply_to: 'fred@zulip.com'},
+        {type: 'private', reply_to: 'Fred@zulip.com'}
+    ));
+}());
+
+(function test_recipient_key() {
+    var message;
+
+    message = {type: 'stream', stream: 'Foo', subject: 'BAR'};
+    assert.equal(util.recipient_key(message), 'foo>bar');
+
+    global.$.trim = function (s) {
+        return s.trim();
+    };
+    message = {type: 'private', reply_to: ' bob@example.com, alice@example.com '};
+    assert.equal(util.recipient_key(message), 'alice@example.com,bob@example.com');
+
+}());
+
+(function test_robust_uri_decode() {
+    assert.equal(util.robust_uri_decode('xxx%3Ayyy'), 'xxx:yyy');
+    assert.equal(util.robust_uri_decode('xxx%3'), 'xxx');
+}());
+
+
+(function test_array_compare() {
+    assert(util.array_compare([], []));
+    assert(util.array_compare([1,2,3], [1,2,3]));
+    assert(!util.array_compare([1,2], [1,2,3]));
+    assert(!util.array_compare([1,2,3], [1,2]));
+}());
+
+