Expand token_user_fields unit test

spec/test_token_user_fields.d

@@ -21,4 +21,10 @@ unittest
     context = p_context_new(input);
     assert(p_parse(context) == P_SUCCESS);
     Start * start = p_result(context);
+    assert(start.pIDs);
+    assert(start.pIDs.id);
+    assert(start.pIDs.id.comments == "# c1\n#  c2\n");
+    assert(start.pIDs.pIDs);
+    assert(start.pIDs.pIDs.id);
+    assert(start.pIDs.pIDs.id.comments == "# s1\n#   s2\n");
 }