Try workaround for test issues in #21425
diff --git a/Lib/test/script_helper.py b/Lib/test/script_helper.py
index 993b199..78c3036 100644
--- a/Lib/test/script_helper.py
+++ b/Lib/test/script_helper.py
@@ -86,6 +86,14 @@
"""
cmd_line = [sys.executable, '-E']
cmd_line.extend(args)
+ # Under Fedora (?), GNU readline can output junk on stderr when initialized,
+ # depending on the TERM setting. Setting TERM=vt100 is supposed to disable
+ # that. References:
+ # - http://reinout.vanrees.org/weblog/2009/08/14/readline-invisible-character-hack.html
+ # - http://stackoverflow.com/questions/15760712/python-readline-module-prints-escape-character-during-import
+ # - http://lists.gnu.org/archive/html/bug-readline/2007-08/msg00004.html
+ env = kw.setdefault('env', {})
+ env.setdefault('TERM', 'vt100')
return subprocess.Popen(cmd_line, stdin=subprocess.PIPE,
stdout=stdout, stderr=stderr,
**kw)