Merge pull request apache#423 from datastax/178

mpenick · mpenick · commit c0b1867bd0ea · 2015-10-20T10:32:49.000-07:00
PYTHON-178 - Make bind ignore extra keys in dict values
diff --git a/cassandra/query.py b/cassandra/query.py
@@ -486,23 +486,24 @@ def bind(self, values):
             * short sequences will be extended to match bind parameters with UNSET_VALUE
             * names may be omitted from a dict with UNSET_VALUE implied.
 
+        .. versionchanged:: 3.0.0
+
+            method will not throw if extra keys are present in bound dict (PYTHON-178)
         """
         if values is None:
             values = ()
         proto_version = self.prepared_statement.protocol_version
         col_meta = self.prepared_statement.column_metadata
-        col_meta_len = len(col_meta)
-        value_len = len(values)
 
         # special case for binding dicts
         if isinstance(values, dict):
-            unbound_values = values.copy()
+            values_dict = values
             values = []
 
             # sort values accordingly
             for col in col_meta:
                 try:
-                    values.append(unbound_values.pop(col.name))
+                    values.append(values_dict[col.name])
                 except KeyError:
                     if proto_version >= 4:
                         values.append(UNSET_VALUE)
@@ -511,10 +512,8 @@ def bind(self, values):
                             'Column name `%s` not found in bound dict.' %
                             (col.name))
 
-            value_len = len(values)
-
-            if unbound_values:
-                raise ValueError("Unexpected arguments provided to bind(): %s" % unbound_values.keys())
+        value_len = len(values)
+        col_meta_len = len(col_meta)
 
         if value_len > col_meta_len:
             raise ValueError(
diff --git a/tests/integration/standard/test_prepared_statements.py b/tests/integration/standard/test_prepared_statements.py
@@ -173,7 +173,7 @@ def _run_too_many_bind_values(self, session):
             self.assertIsInstance(prepared, PreparedStatement)
             self.assertRaises(ValueError, prepared.bind, (1, 2))
 
-    def test_too_many_bind_values_dicts(self):
+    def test_imprecise_bind_values_dicts(self):
         """
         Ensure an error is thrown when attempting to bind the wrong values
         with dict bindings
@@ -189,16 +189,16 @@ def test_too_many_bind_values_dicts(self):
 
         self.assertIsInstance(prepared, PreparedStatement)
 
-        # too many values
-        self.assertRaises(ValueError, prepared.bind, {'k': 1, 'v': 2, 'v2': 3})
+        # too many values is ok - others are ignored
+        prepared.bind({'k': 1, 'v': 2, 'v2': 3})
 
         # right number, but one does not belong
         if PROTOCOL_VERSION < 4:
             # pre v4, the driver bails with key error when 'v' is found missing
             self.assertRaises(KeyError, prepared.bind, {'k': 1, 'v2': 3})
         else:
-            # post v4, the driver uses UNSET_VALUE for 'v' and bails when 'v2' is unbound
-            self.assertRaises(ValueError, prepared.bind, {'k': 1, 'v2': 3})
+            # post v4, the driver uses UNSET_VALUE for 'v' and 'v2' is ignored
+            prepared.bind({'k': 1, 'v2': 3})
 
         # also catch too few variables with dicts
         self.assertIsInstance(prepared, PreparedStatement)
diff --git a/tests/unit/test_parameter_binding.py b/tests/unit/test_parameter_binding.py
@@ -25,6 +25,7 @@
 from cassandra.util import OrderedDict
 
 from six.moves import xrange
+import six
 
 
 class ParamBindingTest(unittest.TestCase):
@@ -147,8 +148,9 @@ def test_dict_missing_routing_key(self):
     def test_missing_value(self):
         self.assertRaises(KeyError, self.bound.bind, {'rk0': 0, 'rk1': 0, 'ck0': 0})
 
-    def test_dict_extra_value(self):
-        self.assertRaises(ValueError, self.bound.bind, {'rk0': 0, 'rk1': 0, 'ck0': 0, 'v0': 0, 'should_not_be_here': 123})
+    def test_extra_value(self):
+        self.bound.bind({'rk0': 0, 'rk1': 0, 'ck0': 0, 'v0': 0, 'should_not_be_here': 123})  # okay to have extra keys in dict
+        self.assertEqual(self.bound.values, [six.b('\x00') * 4] * 4)  # four encoded zeros
         self.assertRaises(ValueError, self.bound.bind, (0, 0, 0, 0, 123))
 
     def test_values_none(self):
