diff --git a/Tests/Fixtures/MockStream/MockStream.php b/Tests/Fixtures/MockStream/MockStream.php
index 179fae2d0..9aa9f3e2f 100644
--- a/Tests/Fixtures/MockStream/MockStream.php
+++ b/Tests/Fixtures/MockStream/MockStream.php
@@ -17,6 +17,8 @@
  */
 class MockStream
 {
+    public $context;
+
     /**
      * Opens file or URL.
      *