Harden code to handle non string values

validata_core/custom_checks/sum_columns_value.py

@@ -52,9 +52,13 @@ class SumColumnsValue(object):
         return val != ''
 
     @staticmethod
-    def is_int(str_value):
+    def is_int(value):
         """ Return True if the given string contains an integer """
-        return INT_RE.match(str_value)
+        if isinstance(value, int):
+            return True
+        if isinstance(value, str):
+            return INT_RE.match(value)
+        return False 
 
     def check_row(self, cells):
         """ Main method """