diff --git a/contrib/python3-whitelist b/contrib/python3-whitelist
--- a/contrib/python3-whitelist
+++ b/contrib/python3-whitelist
@@ -490,6 +490,7 @@
 test-tag.t
 test-tags.t
 test-template-filters.t
+test-transplant.t
 test-treemanifest.t
 test-ui-color.py
 test-ui-config.py
diff --git a/tests/test-transplant.t b/tests/test-transplant.t
--- a/tests/test-transplant.t
+++ b/tests/test-transplant.t
@@ -836,9 +836,9 @@
   $ cd binarysource
   $ echo a > a
   $ hg ci -Am adda a
-  >>> open('b', 'wb').write(b'\0b1')
+  >>> open('b', 'wb').write(b'\0b1') and None
   $ hg ci -Am addb b
-  >>> open('b', 'wb').write(b'\0b2')
+  >>> open('b', 'wb').write(b'\0b2') and None
   $ hg ci -m changeb b
   $ cd ..