Issue #25718: Fixed copying object with state with boolean value is false.

3 files changed, 13 insertions, 2 deletions

diff --git a/Lib/copy.py b/Lib/copy.py
index c227a2e..daf81a3 100644
--- a/Lib/copy.py
+++ b/Lib/copy.py
@@ -315,7 +315,7 @@ def _reconstruct(x, info, deep, memo=None):
     if n > 2:
         state = info[2]
     else:
-        state = {}
+        state = None
     if n > 3:
         listiter = info[3]
     else:
@@ -329,7 +329,7 @@ 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 6b64f10..aefc433 100644
--- a/Lib/test/test_copy.py
+++ b/Lib/test/test_copy.py
@@ -165,6 +165,9 @@ class TestCopy(unittest.TestCase):
                 return cmp(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
 
@@ -395,6 +398,12 @@ class TestCopy(unittest.TestCase):
         x = C([42])
         y = copy.deepcopy(x)
         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.assertTrue(y is not x)
         self.assertTrue(y.foo is not x.foo)
 
diff --git a/Misc/NEWS b/Misc/NEWS
index 4a32e47..716be23 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -20,6 +20,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #25718: Fixed copying object with state with boolean value is false.
+
 - Issue #25742: :func:`locale.setlocale` now accepts a Unicode string for
   its second parameter.