Ensure None is returned if no callback data was provided

Author: pietroalbini

botogram/callbacks.py

@@ -101,7 +101,10 @@ def parse_callback_data(bot, raw):
     if not crypto.compare(crypto.get_hmac(bot, name + data), signature):
         raise crypto.TamperedMessageError
 
-    return name, data.decode("utf-8")
+    if data:
+        return name, data.decode("utf-8")
+    else:
+        return name, None
 
 
 def get_callback_data(bot, name, data=None):

tests/test_callbacks.py

@@ -63,3 +63,9 @@ def test_parse_callback_data(bot):
         hashed_callback_name("test_callback"),
         "this is some data!",
     )
+
+    raw = get_callback_data(bot, "test_callback")
+    assert parse_callback_data(bot, raw) == (
+        hashed_callback_name("test_callback"),
+        None,
+    )