Issue #13583: sqlite3.Row now supports slice indexing.

serhiy-storchaka · serhiy-storchaka · commit 72e731cc03f2 · 2015-03-31T13:33:11.000+03:00
Tests by Jessica McKellar.
diff --git a/Doc/library/sqlite3.rst b/Doc/library/sqlite3.rst
@@ -649,6 +649,9 @@ Row Objects
       This method returns a list of column names. Immediately after a query,
       it is the first member of each tuple in :attr:`Cursor.description`.
 
+   .. versionchanged:: 3.5
+      Added support of slicing.
+
 Let's assume we initialize a table as in the example given above::
 
    conn = sqlite3.connect(":memory:")
diff --git a/Lib/sqlite3/test/factory.py b/Lib/sqlite3/test/factory.py
@@ -111,6 +111,24 @@ def CheckSqliteRowIndex(self):
         with self.assertRaises(IndexError):
             row[2**1000]
 
+    def CheckSqliteRowSlice(self):
+        # A sqlite.Row can be sliced like a list.
+        self.con.row_factory = sqlite.Row
+        row = self.con.execute("select 1, 2, 3, 4").fetchone()
+        self.assertEqual(row[0:0], ())
+        self.assertEqual(row[0:1], (1,))
+        self.assertEqual(row[1:3], (2, 3))
+        self.assertEqual(row[3:1], ())
+        # Explicit bounds are optional.
+        self.assertEqual(row[1:], (2, 3, 4))
+        self.assertEqual(row[:3], (1, 2, 3))
+        # Slices can use negative indices.
+        self.assertEqual(row[-2:-1], (3,))
+        self.assertEqual(row[-2:], (3, 4))
+        # Slicing supports steps.
+        self.assertEqual(row[0:4:2], (1, 3))
+        self.assertEqual(row[3:0:-2], (4, 2))
+
     def CheckSqliteRowIter(self):
         """Checks if the row object is iterable"""
         self.con.row_factory = sqlite.Row
diff --git a/Misc/NEWS b/Misc/NEWS
@@ -13,6 +13,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #13583: sqlite3.Row now supports slice indexing.
+
 - Issue #18473: Fixed 2to3 and 3to2 compatible pickle mappings.  Fixed
   ambigious reverse mappings.  Added many new mappings.  Import mapping is no
   longer applied to modules already mapped with full name mapping.
diff --git a/Modules/_sqlite/row.c b/Modules/_sqlite/row.c
@@ -142,8 +142,7 @@ PyObject* pysqlite_row_subscript(pysqlite_Row* self, PyObject* idx)
         return NULL;
     }
     else if (PySlice_Check(idx)) {
-        PyErr_SetString(PyExc_ValueError, "slices not implemented, yet");
-        return NULL;
+        return PyObject_GetItem(self->data, idx);
     }
     else {
         PyErr_SetString(PyExc_IndexError, "Index must be int or string");

Original file line number	Diff line number	Diff line change
`@@ -142,8 +142,7 @@ PyObject* pysqlite_row_subscript(pysqlite_Row* self, PyObject* idx)`
`142`	`142`	`return NULL;`
`143`	`143`	`}`
`144`	`144`	`else if (PySlice_Check(idx)) {`
`145`		`- PyErr_SetString(PyExc_ValueError, "slices not implemented, yet");`
`146`		`- return NULL;`
	`145`	`+ return PyObject_GetItem(self->data, idx);`
`147`	`146`	`}`
`148`	`147`	`else {`
`149`	`148`	`PyErr_SetString(PyExc_IndexError, "Index must be int or string");`