fix round function for <1

OneSila/currencies/helpers.py

@@ -1,11 +1,22 @@
 import math
 from decimal import Decimal
-
-
 def roundup(x, ceil):
     ''' Roundup a number to the nearest ceiling
-    For example:  roundup(111, 20) returns 120'''
-    return int(math.ceil(x / Decimal(ceil))) * Decimal(ceil)
+    For example:  roundup(111, 20) returns 120
+    If roundup < 1 we round up to the ceil itself
+    '''
+    ceil = Decimal(ceil)
+    integral_part = int(x)
+    fractional_part = x - integral_part
+
+    if ceil < 1:
+        if fractional_part < ceil:
+            return Decimal(integral_part) + ceil
+        else:
+            return Decimal(integral_part) + 1 + ceil
+    else:
+        return Decimal(math.ceil(x / ceil) * ceil)
+
 
 
 def currency_convert(round_prices_up_to, exchange_rate, price):

OneSila/currencies/tests/tests_helpers.py

@@ -14,6 +14,17 @@ def test_currency_convert_dot_99(self):
         expected_amount = 10.99
         self.assertEqual(new_acount, expected_amount)
 
+    def test_currency_convert_10_dot_5_to_dot_4(self):
+        new_acount = float(round(
+            currency_convert(
+                round_prices_up_to=.4,
+                exchange_rate=1,
+                price=10.5,
+            ),
+            2))
+        expected_amount = 11.4
+        self.assertEqual(new_acount, expected_amount)
+
     def test_currency_convert_99(self):
         new_acount = float(round(
             currency_convert(