fix: client duplicate function now allows db param to be passed

Author: markmcnelis

lib/extendedApi.js

@@ -95,7 +95,7 @@ RedisClient.prototype.duplicate = function (options, callback) {
         existing_options[elem] = options[elem];
     }
     var client = new RedisClient(existing_options);
-    client.selected_db = this.selected_db;
+    client.selected_db = options.db || this.selected_db;
     if (typeof callback === 'function') {
         var ready_listener = function () {
             callback(null, client);

test/node_redis.spec.js

@@ -120,11 +120,14 @@ describe('The node_redis client', function () {
                     });
 
                     it('check if all new options replaced the old ones', function (done) {
+                        client.selected_db = 1;
                         var client2 = client.duplicate({
+                            db: 2, 
                             no_ready_check: true
                         });
                         assert(client.connected);
                         assert(!client2.connected);
+                        assert.notEqual(client.selected_db, client2.selected_db);
                         assert.strictEqual(client.options.no_ready_check, undefined);
                         assert.strictEqual(client2.options.no_ready_check, true);
                         assert.notDeepEqual(client.options, client2.options);