- properly handle negative indexes in RowProxy.__getitem__()pr/231

3 files changed, 31 insertions, 1 deletions

diff --git a/lib/sqlalchemy/cextension/resultproxy.c b/lib/sqlalchemy/cextension/resultproxy.c
index a87fe7b56..331fae2b2 100644
--- a/lib/sqlalchemy/cextension/resultproxy.c
+++ b/lib/sqlalchemy/cextension/resultproxy.c
@@ -263,6 +263,8 @@ BaseRowProxy_subscript(BaseRowProxy *self, PyObject *key)
 #if PY_MAJOR_VERSION < 3
     if (PyInt_CheckExact(key)) {
         index = PyInt_AS_LONG(key);
+        if (index < 0)
+            index += BaseRowProxy_length(self);
     } else
 #endif
 
@@ -271,6 +273,8 @@ BaseRowProxy_subscript(BaseRowProxy *self, PyObject *key)
         if ((index == -1) && PyErr_Occurred())
             /* -1 can be either the actual value, or an error flag. */
             return NULL;
+        if (index < 0)
+            index += BaseRowProxy_length(self);
     } else if (PySlice_Check(key)) {
         values = PyObject_GetItem(self->row, key);
         if (values == NULL)
diff --git a/lib/sqlalchemy/engine/result.py b/lib/sqlalchemy/engine/result.py
index 39f4fc50c..9208686e1 100644
--- a/lib/sqlalchemy/engine/result.py
+++ b/lib/sqlalchemy/engine/result.py
@@ -215,10 +215,17 @@ class ResultMetaData(object):
 
         self._keymap = {}
         if not _baserowproxy_usecext:
-            # keymap indexes by integer index...
+            # keymap indexes by integer index: this is only used
+            # in the pure Python BaseRowProxy.__getitem__
+            # implementation to avoid an expensive
+            # isinstance(key, util.int_types) in the most common
+            # case path
             self._keymap.update([
                 (elem[0], (elem[3], elem[4], elem[0]))
                 for elem in raw
+            ] + [
+                (elem[0] - num_ctx_cols, (elem[3], elem[4], elem[0]))
+                for elem in raw
             ])
 
         # processors in key order for certain per-row
diff --git a/test/engine/test_execute.py b/test/engine/test_execute.py
index 5ea5d3515..aadd170f3 100644
--- a/test/engine/test_execute.py
+++ b/test/engine/test_execute.py
@@ -951,6 +951,25 @@ class ResultProxyTest(fixtures.TestBase):
             {'key': (None, None, 0), 0: (None, None, 0)})
         assert isinstance(row, collections.Sequence)
 
+    def test_rowproxy_getitem(self):
+        metadata = MetaData()
+        metadata.bind = 'sqlite://'
+        values = Table('users', metadata,
+                       Column('key', String(10), primary_key=True),
+                       Column('value', String(10)))
+        values.create()
+
+        values.insert().execute(key='One', value='Uno')
+        row = values.select().execute().fetchone()
+
+        assert row['key'] == 'One'
+        assert row['value'] == 'Uno'
+        assert row[0] == 'One'
+        assert row[1] == 'Uno'
+        assert row[-2] == 'One'
+        assert row[-1] == 'Uno'
+        assert row[1:0:-1] == ('Uno',)
+
     @testing.requires.cextensions
     def test_row_c_sequence_check(self):
         import csv