feat(db-ref): support passing a namespace into a DBRef ctor

Author: mbroadst

Diff for: lib/bson/db_ref.js

@@ -11,6 +11,13 @@
 function DBRef(collection, oid, db, fields) {
   if (!(this instanceof DBRef)) return new DBRef(collection, oid, db, fields);
 
+  // check if namespace has been provided
+  var parts = collection.split('.');
+  if (parts.length === 2) {
+    db = parts.shift();
+    collection = parts.shift();
+  }
+
   this._bsontype = 'DBRef';
   this.collection = collection;
   this.oid = oid;

Diff for: lib/bson/parser/deserializer.js

@@ -534,26 +534,14 @@ var deserializeObject = function(buffer, index, options, isArray) {
 
       // Update the index
       index = index + 12;
-
       for (i = 0; i < namespace.length; i++) {
         if (namespace.charCodeAt(i) === 0xfffd) {
           throw new Error('Invalid UTF-8 string in BSON document');
         }
       }
 
-      // Split the namespace
-      var parts = namespace.split('.');
-
-      var db, collection;
-      if (parts.length === 2) {
-        db = parts.shift();
-        collection = parts.shift();
-      } else {
-        collection = namespace;
-      }
-
       // Upgrade to DBRef type
-      object[name] = new DBRef(collection, oid, db);
+      object[name] = new DBRef(namespace, oid);
     } else {
       throw new Error(
         'Detected unknown BSON type ' +