Index: Ringtoets/AssemblyTool/test/Ringtoets.AssemblyTool.IO.TestUtil/InvalidIdTestHelper.cs
===================================================================
diff -u -r46c6e661ed805f0fe44e3a70e865415cf57f0cf6 -r36b9c04c7edcc5527fde3c6f2134d14969ee8e4f
--- Ringtoets/AssemblyTool/test/Ringtoets.AssemblyTool.IO.TestUtil/InvalidIdTestHelper.cs	(.../InvalidIdTestHelper.cs)	(revision 46c6e661ed805f0fe44e3a70e865415cf57f0cf6)
+++ Ringtoets/AssemblyTool/test/Ringtoets.AssemblyTool.IO.TestUtil/InvalidIdTestHelper.cs	(.../InvalidIdTestHelper.cs)	(revision 36b9c04c7edcc5527fde3c6f2134d14969ee8e4f)
@@ -36,10 +36,12 @@
         {
             get
             {
+                yield return new TestCaseData(null);
                 yield return new TestCaseData("");
                 yield return new TestCaseData("   ");
                 yield return new TestCaseData("1nvalidId");
                 yield return new TestCaseData("invalidId#");
+                yield return new TestCaseData("invalid\rId");
             }
         }
     }