Fix bug in varint packing that caused 0s to throw an exception

cassandra/marshal.py

@@ -37,6 +37,8 @@ def bitlength(n):
 
 def varint_pack(big):
     pos = True
+    if big == 0:
+        return '\x00'
     if big < 0:
         bytelength = bitlength(abs(big) - 1) / 8 + 1
         big = (1 << bytelength * 8) + big

tests/unit/test_marshalling.py

@@ -61,6 +61,7 @@ marshalled_value_pairs = (
     # vagaries of internal python ordering for unordered types
     ('\x00\x03\x00\x06\xe3\x81\xbfbob\x00\x04\x00\x00\x00\xc7\x00\x00\x00\x04\xff\xff\xff\xff\x00\x01\\\x00\x04\x00\x00\x00\x00', 'MapType(UTF8Type, Int32Type)', {u'\u307fbob': 199, u'': -1, u'\\': 0}),
     ('\x00\x02\x00\x08@\x14\x00\x00\x00\x00\x00\x00\x00\x08@\x01\x99\x99\x99\x99\x99\x9a', 'SetType(DoubleType)', set([2.2, 5.0])),
+    ('\x00', 'IntegerType', 0),
 )
 
 class TestUnmarshal(unittest.TestCase):