Tpl: add display_ajax_error() helper method

src/Tpl.php

@@ -550,6 +550,26 @@ class Tpl {
     exit();
   }
 
+  /**
+   * Display AJAX error
+   * @param string|null $error Error message (optional)
+   * @param bool $pretty AJAX returned data
+   *             (optional, default: true if $_REQUEST['pretty'] is set, False otherwise)
+   * @return never
+   */
+  public static function display_ajax_error($error=null, $pretty=false) {
+    self :: display_ajax_return(
+      array(
+        'success' => false,
+        'error' => (
+          $error?
+          $error:
+          I18n::_("Unexpected error occured. If problem persist, please contact support.")
+        ),
+      )
+    );
+  }
+
   /**
    * Handle a fatal error
    * @param string $error The error message
@@ -576,7 +596,7 @@ class Tpl {
 
     // Handle API mode
     if (Url :: api_mode())
-      self :: display_ajax_return(array('success' => false, 'error' => $error));
+      self :: display_ajax_error($error);
 
     self :: assign('fatal_error', $error);
     self :: display('fatal_error.tpl');