diff --git a/scripts/dts/testdtlib.py b/scripts/dts/testdtlib.py
index 777e1fd..e03fb5b 100755
--- a/scripts/dts/testdtlib.py
+++ b/scripts/dts/testdtlib.py
@@ -1844,8 +1844,10 @@
 
     verify_raw_to_num_error(dtlib.to_num, 0, 0, "'0' has type 'int', expected 'bytes'")
     verify_raw_to_num_error(dtlib.to_num, b"", 0, "'length' must be greater than zero, was 0")
+    verify_raw_to_num_error(dtlib.to_num, b"foo", 2, "b'foo' is 3 bytes long, expected 2")
     verify_raw_to_num_error(dtlib.to_nums, 0, 0, "'0' has type 'int', expected 'bytes'")
     verify_raw_to_num_error(dtlib.to_nums, b"", 0, "'length' must be greater than zero, was 0")
+    verify_raw_to_num_error(dtlib.to_nums, b"foooo", 2, "b'foooo' is 5 bytes long, expected a length that's a a multiple of 2")
 
     #
     # Test duplicate label error