Merge pull request #132 from RiveraGroup/feature/mongo_2.6.5_documentSource_UnwindDocumentSource

Feature/mongo 2.6.5 document source unwind document source

lib/pipeline/documentSources/UnwindDocumentSource.js

@@ -196,6 +196,17 @@ proto.unwindPath = function unwindPath(fieldPath) {
 	this._unwinder = new klass.Unwinder(fieldPath);
 };
 
+/**
+ * Serialize the data associated with the unwind path.
+ *
+ * @param builder
+ * @param explain
+ */
+proto.serialize = function serialize(builder, explain) {
+	if (!this._unwindPath) throw new Error("unwind path does not exist!");
+	builder[this.getSourceName()] = this._unwindPath.getPath(true);
+};
+
 /**
  * Creates a new UnwindDocumentSource with the input path as the path to unwind
  * @param {String} JsonElement this thing is *called* Json, but it expects a string