+msg="WARNING: Consider using FIELD_MODIFY helper on %s" % (x)
+msg_safe=msg.replace("[","@(").replace("]",")")
+coccilib.org.print_todo(p[0], msg_safe)
How do you think about to use the following code variant instead?
msg = f"WARNING: Consider using FIELD_MODIFY helper on {x}"
coccilib.org.print_todo(p[0], msg.replace("[","@(").replace("]",")"))
Regards,
Markus