"Port" the fix for issue 1974 from the trunk (2.7). Because Python 3.x does things much better, less changes are necessary.

This also shoves test_email_codecs_rename.py onto test_email_codecs.py even though the test needs to be ported to Python 3.

Doc/library/email.header.rst

@@ -72,7 +72,7 @@ Here is the :class:`Header` class description:
 
    Optional *continuation_ws* must be :rfc:`2822`\ -compliant folding whitespace,
    and is usually either a space or a hard tab character. This character will be
-   prepended to continuation lines.
+   prepended to continuation lines. *continuation_ws* defaults to a single space character (" ").
 
    Optional *errors* is passed straight through to the :meth:`append` method.
 

Lib/email/generator.py

@@ -138,7 +138,7 @@ def _write_headers(self, msg):
             else:
                 # Header's got lots of smarts, so use it.
                 header = Header(v, maxlinelen=self._maxheaderlen,
-                                header_name=h, continuation_ws='\t')
+                                header_name=h)
                 print(header.encode(), file=self._fp)
         # A blank line always separates headers from body
         print(file=self._fp)

Lib/email/test/test_email.py

@@ -769,7 +769,7 @@ def test_long_to_header(self):
         msg['To'] = to
         eq(msg.as_string(maxheaderlen=78), '''\
 To: "Someone Test #A" <someone@eecs.umich.edu>,<someone@eecs.umich.edu>,
-\t"Someone Test #B" <someone@umich.edu>,
+ "Someone Test #B" <someone@umich.edu>,
  "Someone Test #C" <someone@eecs.umich.edu>,
  "Someone Test #D" <someone@eecs.umich.edu>
 
@@ -852,7 +852,7 @@ def test_long_unbreakable_lines_with_continuation(self):
         # snug against the field name.
         eq(msg.as_string(maxheaderlen=78), """\
 Face-1:\x20
-\tiVBORw0KGgoAAAANSUhEUgAAADAAAAAwBAMAAAClLOS0AAAAGFBMVEUAAAAkHiJeRUIcGBi9
+ iVBORw0KGgoAAAANSUhEUgAAADAAAAAwBAMAAAClLOS0AAAAGFBMVEUAAAAkHiJeRUIcGBi9
  locQDQ4zJykFBAXJfWDjAAACYUlEQVR4nF2TQY/jIAyFc6lydlG5x8Nyp1Y69wj1PN2I5gzp
 Face-2:\x20
  iVBORw0KGgoAAAANSUhEUgAAADAAAAAwBAMAAAClLOS0AAAAGFBMVEUAAAAkHiJeRUIcGBi9

Lib/email/test/test_email_codecs.py

@@ -6,9 +6,9 @@
 from test.support import run_unittest
 
 from email.test.test_email import TestEmailBase
-from email.Charset import Charset
+from email.charset import Charset
-from email.Header import Header, decode_header
+from email.header import Header, decode_header
-from email.Message import Message
+from email.message import Message
 
 # We're compatible with Python 2.3, but it doesn't have the built-in Asian
 # codecs, so we have to skip all these tests.

Lib/email/test/test_email_codecs_renamed.py

@@ -1,77 +0,0 @@
-# Copyright (C) 2002-2006 Python Software Foundation
-# Contact: email-sig@python.org
-# email package unit tests for (optional) Asian codecs
-
-import unittest
-from test.support import run_unittest
-
-from email.test.test_email import TestEmailBase
-from email.charset import Charset
-from email.header import Header, decode_header
-from email.message import Message
-
-# We're compatible with Python 2.3, but it doesn't have the built-in Asian
-# codecs, so we have to skip all these tests.
-try:
-    str('foo', 'euc-jp')
-except LookupError:
-    raise unittest.SkipTest
-
-
-
-class TestEmailAsianCodecs(TestEmailBase):
-    def test_japanese_codecs(self):
-        eq = self.ndiffAssertEqual
-        j = Charset("euc-jp")
-        g = Charset("iso-8859-1")
-        h = Header("Hello World!")
-        jhello = '\xa5\xcf\xa5\xed\xa1\xbc\xa5\xef\xa1\xbc\xa5\xeb\xa5\xc9\xa1\xaa'
-        ghello = 'Gr\xfc\xdf Gott!'
-        h.append(jhello, j)
-        h.append(ghello, g)
-        # BAW: This used to -- and maybe should -- fold the two iso-8859-1
-        # chunks into a single encoded word.  However it doesn't violate the
-        # standard to have them as two encoded chunks and maybe it's
-        # reasonable <wink> for each .append() call to result in a separate
-        # encoded word.
-        eq(h.encode(), """\
-Hello World! =?iso-2022-jp?b?GyRCJU8lbSE8JW8hPCVrJUkhKhsoQg==?=
- =?iso-8859-1?q?Gr=FC=DF?= =?iso-8859-1?q?_Gott!?=""")
-        eq(decode_header(h.encode()),
-           [('Hello World!', None),
-            ('\x1b$B%O%m!<%o!<%k%I!*\x1b(B', 'iso-2022-jp'),
-            ('Gr\xfc\xdf Gott!', 'iso-8859-1')])
-        int = 'test-ja \xa4\xd8\xc5\xea\xb9\xc6\xa4\xb5\xa4\xec\xa4\xbf\xa5\xe1\xa1\xbc\xa5\xeb\xa4\xcf\xbb\xca\xb2\xf1\xbc\xd4\xa4\xce\xbe\xb5\xc7\xa7\xa4\xf2\xc2\xd4\xa4\xc3\xa4\xc6\xa4\xa4\xa4\xde\xa4\xb9'
-        h = Header(int, j, header_name="Subject")
-        # test a very long header
-        enc = h.encode()
-        # TK: splitting point may differ by codec design and/or Header encoding
-        eq(enc , """\
-=?iso-2022-jp?b?dGVzdC1qYSAbJEIkWEVqOUYkNSRsJD8lYSE8JWskTztKGyhC?=
- =?iso-2022-jp?b?GyRCMnE8VCROPjVHJyRyQlQkQyRGJCQkXiQ5GyhC?=""")
-        # TK: full decode comparison
-        eq(h.__unicode__().encode('euc-jp'), int)
-
-    def test_payload_encoding(self):
-        jhello = '\xa5\xcf\xa5\xed\xa1\xbc\xa5\xef\xa1\xbc\xa5\xeb\xa5\xc9\xa1\xaa'
-        jcode  = 'euc-jp'
-        msg = Message()
-        msg.set_payload(jhello, jcode)
-        ustr = str(msg.get_payload(), msg.get_content_charset())
-        self.assertEqual(jhello, ustr.encode(jcode))
-
-
-
-def suite():
-    suite = unittest.TestSuite()
-    suite.addTest(unittest.makeSuite(TestEmailAsianCodecs))
-    return suite
-
-
-def test_main():
-    run_unittest(TestEmailAsianCodecs)
-
-
-
-if __name__ == '__main__':
-    unittest.main(defaultTest='suite')