stricter condition on fail

Author: anton-seaice

tests/test_test_bit_reproducibility.py

@@ -112,9 +112,12 @@ def create_mock_output(self, output="output000", modify=False):
                 restart = mom_restart_pointer.parent / restart_file
                 rootgrp = Dataset(restart, "a")
                 for variable in sorted(rootgrp.variables):
+                    # find the first var with a checksum and add 1 to it
                     var = rootgrp[variable]
                     if "checksum" in var.ncattrs():
-                        var.setncattr("checksum", var.checksum.strip() + "0")
+                        # add 1 to the checksum and return as uppercase
+                        var_p1 = format(int(var.checksum, 16)-1, 'X')
+                        var.setncattr("checksum", var_p1)
                         break
                 rootgrp.close()
             else: