Merge pull request #604 from ryanseys/select-single-prop

datastore: add select support for single property

lib/datastore/query.js

@@ -180,16 +180,20 @@ Query.prototype.groupBy = function(fieldNames) {
  *
  * *[More information on projection queries](http://goo.gl/EfsrJl).*
  *
- * @param {array} fieldNames - Properties to return from the matched entities.
+ * @param {string|string[]} fieldNames - Properties to return from the matched
+ *     entities.
  * @return {module:datastore/query}
  *
  * @example
+ * // Only retrieve the name property.
+ * var selectQuery = companyQuery.select('name');
+ *
  * // Only retrieve the name and size properties.
  * var selectQuery = companyQuery.select(['name', 'size']);
  */
 Query.prototype.select = function(fieldNames) {
   var query = extend(new Query(), this);
-  query.selectVal = fieldNames;
+  query.selectVal = util.arrayize(fieldNames);
   return query;
 };
 

test/datastore/query.js

@@ -63,6 +63,12 @@ describe('Query', function() {
     assert.equal(query.selectVal[1], 'title');
   });
 
+  it('should support single field selection by field name', function() {
+    var query = new Query(['kind1'])
+        .select('name');
+    assert.equal(query.selectVal[0], 'name');
+  });
+
   it('should support ancestor filtering', function() {
     var query = new Query(['kind1'])
         .hasAncestor(['kind2', 123]);