diff --git a/tests/test-commandserver.t b/tests/test-commandserver.t
--- a/tests/test-commandserver.t
+++ b/tests/test-commandserver.t
@@ -298,7 +298,7 @@ Clean hook cached version
   ... 
   ...     runcommand(server, ['bookmarks', 'bm3'])
   ...     f = open('a', 'ab')
-  ...     f.write('a\n')
+  ...     f.write('a\n') and None
   ...     f.close()
   ...     runcommand(server, ['commit', '-Amm'])
   ...     runcommand(server, ['bookmarks'])
@@ -391,7 +391,7 @@ Clean hook cached version
   ...     readchannel(server)
   ...     runcommand(server, ['commit', '-Am.'])
   ...     f = open('ignored-file', 'ab')
-  ...     f.write('')
+  ...     f.write('') and None
   ...     f.close()
   ...     f = open('.hgignore', 'ab')
   ...     f.write('ignored-file')
@@ -418,7 +418,7 @@ cache of non-public revisions should be 
   ...     for i in range(5, 7):
   ...         f = open('a', 'ab')
   ...         f.seek(0, os.SEEK_END)
-  ...         f.write('a\n')
+  ...         f.write('a\n') and None
   ...         f.close()
   ...         os.system('hg commit -Aqm%d' % i)
   ...     # new commits should be listed as draft revisions
@@ -463,7 +463,7 @@ cache of phase roots should be invalidat
   ...     # create new head, 5:731265503d86
   ...     runcommand(server, ['update', '-C', '0'])
   ...     f = open('a', 'ab')
-  ...     f.write('a\n')
+  ...     f.write('a\n') and None
   ...     f.close()
   ...     runcommand(server, ['commit', '-Am.', 'a'])
   ...     runcommand(server, ['log', '-Gq'])
diff --git a/tests/test-keyword.t b/tests/test-keyword.t
--- a/tests/test-keyword.t
+++ b/tests/test-keyword.t
@@ -217,7 +217,7 @@ hg status of kw-ignored binary file star
   >>> open("i", "wb").write("\1\nfoo") and None
   $ hg -q commit -Am metasep i
   $ hg status
-  >>> open("i", "wb").write("\1\nbar")
+  >>> open("i", "wb").write("\1\nbar") and None
   $ hg status
   M i
   $ hg -q commit -m "modify metasep" i
@@ -943,7 +943,7 @@ Imported patch should not be rejected
 
   >>> import re
   >>> text = re.sub(r'(Id.*)', r'\1 rejecttest', open('a').read())
-  >>> open('a', 'wb').write(text)
+  >>> open('a', 'wb').write(text) and None
   $ hg --debug commit -m'rejects?' -d '3 0' -u 'User Name <user@example.com>'
   committing files:
   a
diff --git a/tests/test-largefiles-wireproto.t b/tests/test-largefiles-wireproto.t
--- a/tests/test-largefiles-wireproto.t
+++ b/tests/test-largefiles-wireproto.t
@@ -243,7 +243,7 @@ Archive contains largefiles
   >>> import urllib2
   >>> u = 'http://localhost:%s/archive/default.zip' % os.environ['HGPORT2']
   >>> with open('archive.zip', 'w') as f:
-  ...     f.write(urllib2.urlopen(u).read())
+  ...     f.write(urllib2.urlopen(u).read()) and None
   $ unzip -t archive.zip
   Archive:  archive.zip
       testing: empty-default/.hg_archival.txt*OK (glob)
diff --git a/tests/test-lfs.t b/tests/test-lfs.t
--- a/tests/test-lfs.t
+++ b/tests/test-lfs.t
@@ -327,9 +327,9 @@ enabled adds the lfs requirement
   $ hg commit -m b
   $ hg status
   >>> with open('a2', 'wb') as f:
-  ...     f.write(b'\1\nSTART-WITH-HG-FILELOG-METADATA')
+  ...     f.write(b'\1\nSTART-WITH-HG-FILELOG-METADATA') and None
   >>> with open('a1', 'wb') as f:
-  ...     f.write(b'\1\nMETA\n')
+  ...     f.write(b'\1\nMETA\n') and None
   $ hg commit -m meta
   $ hg status
   $ hg log -T '{rev}: {file_copies} | {file_dels} | {file_adds}\n'