[3.5] bpo-29532: Altering a kwarg dictionary passed to functools.partial() no longer affects a partial object after creation. (#222)

1 files changed, 9 insertions, 0 deletions

diff --git a/Lib/test/test_functools.py b/Lib/test/test_functools.py
index 9ccd0ca..a82ca7a 100644
--- a/Lib/test/test_functools.py
+++ b/Lib/test/test_functools.py
@@ -80,6 +80,15 @@ class TestPartial:
         p(b=7)
         self.assertEqual(d, {'a':3})
 
+    def test_kwargs_copy(self):
+        # Issue #29532: Altering a kwarg dictionary passed to a constructor
+        # should not affect a partial object after creation
+        d = {'a': 3}
+        p = self.partial(capture, **d)
+        self.assertEqual(p(), ((), {'a': 3}))
+        d['a'] = 5
+        self.assertEqual(p(), ((), {'a': 3}))
+
     def test_arg_combinations(self):
         # exercise special code paths for zero args in either partial
         # object or the caller