Harden code to handle non string values

validata_core/custom_checks/compare_columns_value.py

@@ -101,20 +101,40 @@ class CompareColumnsValue(object):
                             .format(self.column, value1, OP_LABELS[self.op], self.column2, value2),
                             {'column1': self.column, 'value1': value1, 'column2': self.column2, 'value2': value2, 'op': OP_LABELS[self.op]})
 
+    @staticmethod
+    def is_a_number(value):
+        """Return True if value is an int, a float or a string representation of a number."""
+        if type(value) in (int, float):
+            return True
+        if not isinstance(value, str):
+            return False
+        if value.isnumeric():
+            return True
+        try:
+            float(value)
+            return True
+        except ValueError:
+            return False
+
+
     @staticmethod
     def compute_comparison_str(value1, op, value2):
         """ Computes comparison_str """
 
         # number vs number
-        if value1.isnumeric() and value2.isnumeric():
+        if CompareColumnsValue.is_a_number(value1) and CompareColumnsValue.is_a_number(value2):
             return '{} {} {}'.format(value1, op, value2)
 
         # string vs string
-        if not value1.isnumeric() and not value2.isnumeric():
+        if isinstance(value1, str) and isinstance(value2, str):
             n_value1 = value1.replace('"', '\\"')
             n_value2 = value2.replace('"', '\\"')
             return '"{}" {} "{}"'.format(n_value1, op, n_value2)
 
+        # thing vs thing, compare string repr
+        if type(value1) == type(value2):
+            return f"'{value1}' {op} '{value2}'"
+
         # potato vs cabbage?
         return None