From: Gregory P. Smith <greg@mad-scientist.com>
Date: Fri, 24 Aug 2007 05:26:15 +0000 (+0000)
Subject: backport of r57378 to fix bug 1725856
X-Git-Tag: v2.5.2c1~212
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=838c33268b70c140a38ade92448492a5e796f488;p=python

backport of r57378 to fix bug 1725856
---

diff --git a/Lib/bsddb/__init__.py b/Lib/bsddb/__init__.py
index cf32668862..7eb625cdea 100644
--- a/Lib/bsddb/__init__.py
+++ b/Lib/bsddb/__init__.py
@@ -274,12 +274,16 @@ class _DBWithCursor(_iter_mixin):
 
     def first(self):
         self._checkOpen()
+        # fix 1725856: don't needlessly try to restore our cursor position
+        self.saved_dbc_key = None
         self._checkCursor()
         rv = _DeadlockWrap(self.dbc.first)
         return rv
 
     def last(self):
         self._checkOpen()
+        # fix 1725856: don't needlessly try to restore our cursor position
+        self.saved_dbc_key = None
         self._checkCursor()
         rv = _DeadlockWrap(self.dbc.last)
         return rv
diff --git a/Lib/test/test_bsddb.py b/Lib/test/test_bsddb.py
index 474f3da42b..9ec0cd2bca 100755
--- a/Lib/test/test_bsddb.py
+++ b/Lib/test/test_bsddb.py
@@ -127,6 +127,22 @@ class TestBSDDB(unittest.TestCase):
             items.append(self.f.previous())
         self.assertSetEquals(items, self.d.items())
 
+    def test_first_while_deleting(self):
+        # Test for bug 1725856
+        self.assert_(len(self.d) >= 2, "test requires >=2 items")
+        for _ in self.d:
+            key = self.f.first()[0]
+            del self.f[key]
+        self.assertEqual([], self.f.items(), "expected empty db after test")
+
+    def test_last_while_deleting(self):
+        # Test for bug 1725856's evil twin
+        self.assert_(len(self.d) >= 2, "test requires >=2 items")
+        for _ in self.d:
+            key = self.f.last()[0]
+            del self.f[key]
+        self.assertEqual([], self.f.items(), "expected empty db after test")
+
     def test_set_location(self):
         self.assertEqual(self.f.set_location('e'), ('e', self.d['e']))