Fixed erroneous calculation in calculate_checksum

fra87 · fra87 · commit daf138b6971b · 2023-08-28T20:08:37.000+02:00
diff --git a/barcode/ean.py b/barcode/ean.py
@@ -84,9 +84,10 @@ def calculate_checksum(self):
 
         def sum_(x, y):
             return int(x) + int(y)
-
-        evensum = reduce(sum_, self.ean[-2::-2])
-        oddsum = reduce(sum_, self.ean[-1::-2])
+        ean_without_checksum = self.ean[:self.digits]
+        
+        evensum = reduce(sum_, ean_without_checksum[-2::-2])
+        oddsum = reduce(sum_, ean_without_checksum[-1::-2])
         return (10 - ((evensum + oddsum * 3) % 10)) % 10
 
     def build(self):
