diff --git a/src/applications/auth/management/PhabricatorAuthManagementRevokeWorkflow.php b/src/applications/auth/management/PhabricatorAuthManagementRevokeWorkflow.php
--- a/src/applications/auth/management/PhabricatorAuthManagementRevokeWorkflow.php
+++ b/src/applications/auth/management/PhabricatorAuthManagementRevokeWorkflow.php
@@ -60,7 +60,7 @@
 
     $type = $args->getArg('type');
     $is_everything = $args->getArg('everything');
-    if (!strlen($type) && !$is_everything) {
+    if ($type === null && !$is_everything) {
       if ($is_list) {
         // By default, "bin/revoke --list" implies "--everything".
         $types = $all_types;
@@ -94,7 +94,7 @@
     $from = $args->getArg('from');
 
     if ($is_list) {
-      if (strlen($from) || $is_everywhere) {
+      if ($from !== null || $is_everywhere) {
         throw new PhutilArgumentUsageException(
           pht(
             'You can not "--list" and revoke credentials (with "--from" or '.
diff --git a/src/applications/transactions/editor/PhabricatorApplicationTransactionEditor.php b/src/applications/transactions/editor/PhabricatorApplicationTransactionEditor.php
--- a/src/applications/transactions/editor/PhabricatorApplicationTransactionEditor.php
+++ b/src/applications/transactions/editor/PhabricatorApplicationTransactionEditor.php
@@ -226,7 +226,7 @@
 
   public function getHeraldRuleMonograms() {
     // Convert the stored "<123>, <456>" string into a list: "H123", "H456".
-    $list = $this->heraldHeader;
+    $list = phutil_string_cast($this->heraldHeader);
     $list = preg_split('/[, ]+/', $list);
 
     foreach ($list as $key => $item) {
@@ -2920,7 +2920,7 @@
    * @return bool True if the field will be an empty text field after edits.
    */
   protected function validateIsEmptyTextField($field_value, array $xactions) {
-    if (strlen($field_value) && empty($xactions)) {
+    if (($field_value !== null && strlen($field_value)) && empty($xactions)) {
       return false;
     }