diff --git a/Datastore/src/Connection/Rest.php b/Datastore/src/Connection/Rest.php
index 8636917c52da..b1ecccd6d00a 100644
--- a/Datastore/src/Connection/Rest.php
+++ b/Datastore/src/Connection/Rest.php
@@ -77,8 +77,8 @@ public function allocateIds(array $args)
      */
     public function beginTransaction(array $args)
     {
-        $this->setReadTime($args);
-        return $this->send('projects', 'beginTransaction', $args);
+        $argsWithReadTime = $this->setReadTime($args);
+        return $this->send('projects', 'beginTransaction', $argsWithReadTime);
     }
 
     /**
@@ -94,8 +94,8 @@ public function commit(array $args)
      */
     public function lookup(array $args)
     {
-        $this->setReadTime($args);
-        return $this->send('projects', 'lookup', $args);
+        $argsWithReadTime = $this->setReadTime($args);
+        return $this->send('projects', 'lookup', $argsWithReadTime);
     }
 
     /**
@@ -111,27 +111,29 @@ public function rollback(array $args)
      */
     public function runQuery(array $args)
     {
-        $this->setReadTime($args);
-        return $this->send('projects', 'runQuery', $args);
+        $argsWithReadTime = $this->setReadTime($args);
+        return $this->send('projects', 'runQuery', $argsWithReadTime);
     }
 
     /**
      * @param array $args
      */
-    private function setReadTime(array &$args)
+    private function setReadTime(array $args)
     {
         if (isset($args['readOptions']['readTime'])) {
-            $time = $args['readOptions']['readTime']->getSeconds();
-            $date = date('Y/m/d H:i:s.u\Z', $time);
-            $args['readOptions']['readTime'] = new Timestamp(
-                new \DateTime($date)
-            );
+            $this->setReadTimeOption($args['readOptions']['readTime']);
         } elseif (isset($args['transactionOptions']['readOnly']['readTime'])) {
-            $time = $args['transactionOptions']['readOnly']['readTime']->getSeconds();
-            $date = date('Y/m/d H:i:s.u\Z', $time);
-            $args['transactionOptions']['readOnly']['readTime'] = new Timestamp(
-                new \DateTime($date)
-            );
+            $this->setReadTimeOption($args['transactionOptions']['readOnly']['readTime']);
         }
+        return $args;
+    }
+
+    /**
+     * @param timestamp $readTime
+     */
+    private function setReadTimeOption(&$readTime)
+    {
+        $date = date('Y/m/d H:i:s.u\Z', $readTime->getSeconds());
+        $readTime = new Timestamp(new \DateTime($date));
     }
 }
diff --git a/Datastore/tests/System/RunQueryTest.php b/Datastore/tests/System/RunQueryTest.php
index 06ac632a16ec..b3a8f0683ee3 100644
--- a/Datastore/tests/System/RunQueryTest.php
+++ b/Datastore/tests/System/RunQueryTest.php
@@ -363,20 +363,14 @@ public function testRunQueryWithReadTime(DatastoreClient $client)
             ->kind($kind)
             ->filter('__key__', '=', $key);
         $result = $client->runQuery($query);
-        $personListEntities = [];
-        foreach ($result as $person) {
-            $personListEntities[] = $person;
-        }
+        $personListEntities = iterator_to_array($result);
 
         // Person lastName should be the lastName AFTER update
         $this->assertEquals($personListEntities[0]['lastName'], $newLastName);
 
         // Person lastName should be the lastName BEFORE update
         $result = $client->runQuery($query, ['readTime' => $time]);
-        $personListEntities = [];
-        foreach ($result as $person) {
-            $personListEntities[] = $person;
-        }
+        $personListEntities = iterator_to_array($result);
         $this->assertEquals($personListEntities[0]['lastName'], $lastName);
     }
 
diff --git a/Datastore/tests/System/RunTransactionTest.php b/Datastore/tests/System/RunTransactionTest.php
index d177ccb8551e..b4e30dec4e42 100644
--- a/Datastore/tests/System/RunTransactionTest.php
+++ b/Datastore/tests/System/RunTransactionTest.php
@@ -117,11 +117,7 @@ public function testTransactionWithReadTime(DatastoreClient $client)
             ->filter('__key__', '=', $key)
             ->hasAncestor($ancKey);
         $result = $client->runQuery($query);
-        $personListEntities = [];
-        foreach ($result as $person) {
-            $personListEntities[] = $person;
-        }
-
+        $personListEntities = iterator_to_array($result);
         // Person lastName should be the lastName AFTER update
         $this->assertEquals($personListEntities[0]['lastName'], $newLastName);
 
@@ -130,10 +126,7 @@ public function testTransactionWithReadTime(DatastoreClient $client)
         );
         // runQuery function: Person lastName should be the lastName BEFORE update
         $persons = $transaction2->runQuery($query);
-        $personListEntities = [];
-        foreach ($persons as $person) {
-            $personListEntities[] = $person;
-        }
+        $personListEntities = iterator_to_array($persons);
         $this->assertEquals($personListEntities[0]['lastName'], $lastName);
 
         // lookUp function: Person lastName should be the lastName BEFORE update