diff --git a/src/applications/transactions/editor/PhabricatorEditEngineConfigurationEditor.php b/src/applications/transactions/editor/PhabricatorEditEngineConfigurationEditor.php
index 320a1981b6..d394e87266 100644
--- a/src/applications/transactions/editor/PhabricatorEditEngineConfigurationEditor.php
+++ b/src/applications/transactions/editor/PhabricatorEditEngineConfigurationEditor.php
@@ -1,201 +1,203 @@
 <?php
 
 final class PhabricatorEditEngineConfigurationEditor
   extends PhabricatorApplicationTransactionEditor {
 
   public function getEditorApplicationClass() {
     return 'PhabricatorTransactionsApplication';
   }
 
   public function getEditorObjectsDescription() {
     return pht('Edit Configurations');
   }
 
   public function getTransactionTypes() {
     $types = parent::getTransactionTypes();
 
     $types[] = PhabricatorTransactions::TYPE_VIEW_POLICY;
 
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_NAME;
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_PREAMBLE;
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_ORDER;
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULT;
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_LOCKS;
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_SUBTYPE;
     $types[] =
       PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULTCREATE;
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_ISEDIT;
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_DISABLE;
 
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_CREATEORDER;
     $types[] = PhabricatorEditEngineConfigurationTransaction::TYPE_EDITORDER;
 
     return $types;
   }
 
   protected function validateTransaction(
     PhabricatorLiskDAO $object,
     $type,
     array $xactions) {
 
     $errors = parent::validateTransaction($object, $type, $xactions);
     switch ($type) {
       case PhabricatorEditEngineConfigurationTransaction::TYPE_NAME:
         $missing = $this->validateIsEmptyTextField(
           $object->getName(),
           $xactions);
 
         if ($missing) {
           $error = new PhabricatorApplicationTransactionValidationError(
             $type,
             pht('Required'),
             pht('Form name is required.'),
             nonempty(last($xactions), null));
 
           $error->setIsMissingFieldError(true);
           $errors[] = $error;
         }
         break;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_SUBTYPE:
-        $map = $object->getEngine()
-          ->setViewer($this->getActor())
-          ->newSubtypeMap();
-        foreach ($xactions as $xaction) {
-          $new = $xaction->getNewValue();
-
-          if (isset($map[$new])) {
-            continue;
+        if ($xactions) {
+          $map = $object->getEngine()
+            ->setViewer($this->getActor())
+            ->newSubtypeMap();
+          foreach ($xactions as $xaction) {
+            $new = $xaction->getNewValue();
+
+            if (isset($map[$new])) {
+              continue;
+            }
+
+            $errors[] = new PhabricatorApplicationTransactionValidationError(
+              $type,
+              pht('Invalid'),
+              pht('Subtype "%s" is not a valid subtype.', $new),
+              $xaction);
           }
-
-          $errors[] = new PhabricatorApplicationTransactionValidationError(
-            $type,
-            pht('Invalid'),
-            pht('Subtype "%s" is not a valid subtype.', $new),
-            $xaction);
         }
         break;
     }
 
     return $errors;
   }
 
   protected function getCustomTransactionOldValue(
     PhabricatorLiskDAO $object,
     PhabricatorApplicationTransaction $xaction) {
 
     switch ($xaction->getTransactionType()) {
       case PhabricatorEditEngineConfigurationTransaction::TYPE_NAME:
         return $object->getName();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_PREAMBLE;
         return $object->getPreamble();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_ORDER:
         return $object->getFieldOrder();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULT:
         $field_key = $xaction->getMetadataValue('field.key');
         return $object->getFieldDefault($field_key);
       case PhabricatorEditEngineConfigurationTransaction::TYPE_LOCKS:
         return $object->getFieldLocks();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_SUBTYPE:
         return $object->getSubtype();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULTCREATE:
         return (int)$object->getIsDefault();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_ISEDIT:
         return (int)$object->getIsEdit();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DISABLE:
         return (int)$object->getIsDisabled();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_CREATEORDER:
         return (int)$object->getCreateOrder();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_EDITORDER:
         return (int)$object->getEditOrder();
 
     }
   }
 
   protected function getCustomTransactionNewValue(
     PhabricatorLiskDAO $object,
     PhabricatorApplicationTransaction $xaction) {
 
     switch ($xaction->getTransactionType()) {
       case PhabricatorEditEngineConfigurationTransaction::TYPE_NAME:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_PREAMBLE;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_ORDER:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULT:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_LOCKS:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_SUBTYPE:
         return $xaction->getNewValue();
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULTCREATE:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_ISEDIT:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DISABLE:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_CREATEORDER:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_EDITORDER:
         return (int)$xaction->getNewValue();
     }
   }
 
   protected function applyCustomInternalTransaction(
     PhabricatorLiskDAO $object,
     PhabricatorApplicationTransaction $xaction) {
 
     switch ($xaction->getTransactionType()) {
       case PhabricatorEditEngineConfigurationTransaction::TYPE_NAME:
         $object->setName($xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_PREAMBLE;
         $object->setPreamble($xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_ORDER:
         $object->setFieldOrder($xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULT:
         $field_key = $xaction->getMetadataValue('field.key');
         $object->setFieldDefault($field_key, $xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_LOCKS:
         $object->setFieldLocks($xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_SUBTYPE:
         $object->setSubtype($xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULTCREATE:
         $object->setIsDefault($xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_ISEDIT:
         $object->setIsEdit($xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DISABLE:
         $object->setIsDisabled($xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_CREATEORDER:
         $object->setCreateOrder($xaction->getNewValue());
         return;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_EDITORDER:
         $object->setEditOrder($xaction->getNewValue());
         return;
     }
 
     return parent::applyCustomInternalTransaction($object, $xaction);
   }
 
   protected function applyCustomExternalTransaction(
     PhabricatorLiskDAO $object,
     PhabricatorApplicationTransaction $xaction) {
 
     switch ($xaction->getTransactionType()) {
       case PhabricatorEditEngineConfigurationTransaction::TYPE_NAME:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_PREAMBLE;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_ORDER;
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULT:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_ISEDIT:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_LOCKS:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_SUBTYPE:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DEFAULTCREATE:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_DISABLE:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_CREATEORDER:
       case PhabricatorEditEngineConfigurationTransaction::TYPE_EDITORDER:
         return;
     }
 
     return parent::applyCustomExternalTransaction($object, $xaction);
   }
 
 }