From cbbec1c53f4b6fb88b4ae984e69db2d2951cd560 Mon Sep 17 00:00:00 2001
From: Serhiy Storchaka <storchaka@gmail.com>
Date: Mon, 30 Nov 2015 17:20:02 +0200
Subject: [PATCH] Issue #25718: Fixed copying object with state with boolean
 value is false.

---
 Lib/copy.py           | 4 ++--
 Lib/test/test_copy.py | 9 +++++++++
 Misc/NEWS             | 2 ++
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/Lib/copy.py b/Lib/copy.py
index bb8840ed549..f0fb4437776 100644
--- a/Lib/copy.py
+++ b/Lib/copy.py
@@ -281,7 +281,7 @@ def _reconstruct(x, info, deep, memo=None):
     if n > 2:
         state = info[2]
     else:
-        state = {}
+        state = None
     if n > 3:
         listiter = info[3]
     else:
@@ -295,7 +295,7 @@ def _reconstruct(x, info, deep, memo=None):
     y = callable(*args)
     memo[id(x)] = y
 
-    if state:
+    if state is not None:
         if deep:
             state = deepcopy(state, memo)
         if hasattr(y, '__setstate__'):
diff --git a/Lib/test/test_copy.py b/Lib/test/test_copy.py
index eb8d18cf0b1..0c5354c65c8 100644
--- a/Lib/test/test_copy.py
+++ b/Lib/test/test_copy.py
@@ -180,6 +180,9 @@ class TestCopy(unittest.TestCase):
                 return self.foo == other.foo
         x = C(42)
         self.assertEqual(copy.copy(x), x)
+        # State with boolean value is false (issue #25718)
+        x = C(0.0)
+        self.assertEqual(copy.copy(x), x)
 
     # The deepcopy() method
 
@@ -448,6 +451,12 @@ class TestCopy(unittest.TestCase):
         self.assertEqual(y, x)
         self.assertIsNot(y, x)
         self.assertIsNot(y.foo, x.foo)
+        # State with boolean value is false (issue #25718)
+        x = C([])
+        y = copy.deepcopy(x)
+        self.assertEqual(y, x)
+        self.assertIsNot(y, x)
+        self.assertIsNot(y.foo, x.foo)
 
     def test_deepcopy_reflexive_inst(self):
         class C:
diff --git a/Misc/NEWS b/Misc/NEWS
index 95f2626f26e..c7a13948a39 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -113,6 +113,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #25718: Fixed copying object with state with boolean value is false.
+
 - Issue #10131: Fixed deep copying of minidom documents.  Based on patch
   by Marian Ganisin.