diff -r 13ad4a34fa87 Lib/test/test_base64.py
--- a/Lib/test/test_base64.py	Mon May 18 13:21:21 2015 -0700
+++ b/Lib/test/test_base64.py	Sun May 24 13:15:59 2015 -0700
@@ -3,10 +3,8 @@
 import base64
 import binascii
 import os
-import sys
-import subprocess
-import struct
 from array import array
+from test.support import script_helper
 
 
 class LegacyBase64TestCase(unittest.TestCase):
@@ -622,19 +620,14 @@
         self.assertTrue(issubclass(binascii.Error, ValueError))
 
 
-
 class TestMain(unittest.TestCase):
     def tearDown(self):
         if os.path.exists(support.TESTFN):
             os.unlink(support.TESTFN)
 
-    def get_output(self, *args, **options):
-        args = (sys.executable, '-m', 'base64') + args
-        return subprocess.check_output(args, **options)
-
     def test_encode_decode(self):
-        output = self.get_output('-t')
-        self.assertSequenceEqual(output.splitlines(), (
+        result = script_helper.assert_python_ok('-m', 'base64', '-t')
+        self.assertSequenceEqual(result.out.splitlines(), (
             b"b'Aladdin:open sesame'",
             br"b'QWxhZGRpbjpvcGVuIHNlc2FtZQ==\n'",
             b"b'Aladdin:open sesame'",
@@ -643,20 +636,21 @@
     def test_encode_file(self):
         with open(support.TESTFN, 'wb') as fp:
             fp.write(b'a\xffb\n')
+        result = script_helper.assert_python_ok('-m', 'base64', '-e', support.TESTFN)
+        self.assertEqual(result.out.rstrip(), b'Yf9iCg==')
 
-        output = self.get_output('-e', support.TESTFN)
-        self.assertEqual(output.rstrip(), b'Yf9iCg==')
-
-        with open(support.TESTFN, 'rb') as fp:
-            output = self.get_output('-e', stdin=fp)
-        self.assertEqual(output.rstrip(), b'Yf9iCg==')
+    def test_encode_from_stdin(self):
+        input = b'a\xffb\n'
+        p = script_helper.run_python('-m', 'base64', '-e')
+        p.stdin.write(input)
+        result = script_helper.wait_for_process(p)
+        self.assertEqual(result.out.rstrip(), b'Yf9iCg==')
 
     def test_decode(self):
         with open(support.TESTFN, 'wb') as fp:
             fp.write(b'Yf9iCg==')
-        output = self.get_output('-d', support.TESTFN)
-        self.assertEqual(output.rstrip(), b'a\xffb')
-
+        result = script_helper.assert_python_ok('-m', 'base64', '-d', support.TESTFN)
+        self.assertEqual(result.out.rstrip(), b'a\xffb')
 
 
 def test_main():