Raise TypeErr when bad CF attr type is supplied

Fixes pycassa#99

pycassa/system_manager.py

@@ -249,7 +249,16 @@ def _system_add_column_family(self, cfdef):
 
     def _qualify_type_class(self, classname):
         if classname:
-            s = str(classname)
+            if isinstance(classname, types.CassandraType):
+                s = str(classname)
+            elif isinstance(classname, basestring):
+                s = classname
+            else:
+                raise TypeError(
+                        "Column family validators and comparators " \
+                        "must be specified as instances of " \
+                        "pycassa.types.CassandraType subclasses or strings.")
+
             if s.find('.') == -1:
                 return 'org.apache.cassandra.db.marshal.%s' % s
             else:

tests/test_system_manager.py

@@ -1,11 +1,12 @@
 import unittest
 
-from nose.tools import assert_equal
+from nose.tools import assert_equal, assert_raises
 
 from pycassa.pool import ConnectionPool
 from pycassa.columnfamily import ColumnFamily
 from pycassa.system_manager import *
 from pycassa.cassandra.ttypes import InvalidRequestException
+from pycassa.types import LongType
 
 TEST_KS = 'PycassaTestKeyspace'
 
@@ -40,6 +41,13 @@ def test_system_calls(self):
 
         sys.drop_keyspace('TestKeyspace')
 
+    def test_bad_comparator(self):
+        sys.create_keyspace('TestKeyspace', SIMPLE_STRATEGY, {'replication_factor': '3'})
+        for comparator in [types.LongType, 123]:
+            assert_raises(TypeError, sys.create_column_family,
+                    'TestKeyspace', 'TestBadCF', comparator_type=comparator)
+        sys.drop_keyspace('TestKeyspace')
+
     def test_alter_column_non_bytes_type(self):
         sys.create_column_family(TEST_KS, 'LongCF', comparator_type=LONG_TYPE)
         sys.create_index(TEST_KS, 'LongCF', 3, LONG_TYPE)