merge #11584: make decode_header handle Header objects correctly

This updates 12e39cd7a0e4 (merge of b21fdfa0019c), which fixed this bug
incorrectly.

2 files changed, 5 insertions, 4 deletions

diff --git a/Lib/email/header.py b/Lib/email/header.py
index 0a66df5..0670885 100644
--- a/Lib/email/header.py
+++ b/Lib/email/header.py
@@ -73,9 +73,10 @@ def decode_header(header):
     An email.errors.HeaderParseError may be raised when certain decoding error
     occurs (e.g. a base64 decoding exception).
     """
-    # If it is a Header object, we can just return the chunks.
+    # If it is a Header object, we can just return the encoded chunks.
     if hasattr(header, '_chunks'):
-        return list(header._chunks)
+        return [(_charset._encode(string, str(charset)), str(charset))
+                    for string, charset in header._chunks]
     # If no encoding, just return the header with no charset.
     if not ecre.search(header):
         return [(header, None)]
diff --git a/Lib/test/test_email/test_email.py b/Lib/test/test_email/test_email.py
index 1657afc..aad565c 100644
--- a/Lib/test/test_email/test_email.py
+++ b/Lib/test/test_email/test_email.py
@@ -4324,8 +4324,8 @@ A very long line that must get split to something other than at the
 
     def test_escaped_8bit_header(self):
         x = b'Ynwp4dUEbay Auction Semiar- No Charge \x96 Earn Big'
-        x = x.decode('ascii', 'surrogateescape')
-        h = Header(x, charset=email.charset.UNKNOWN8BIT)
+        e = x.decode('ascii', 'surrogateescape')
+        h = Header(e, charset=email.charset.UNKNOWN8BIT)
         self.assertEqual(str(h),
                         'Ynwp4dUEbay Auction Semiar- No Charge \uFFFD Earn Big')
         self.assertEqual(email.header.decode_header(h), [(x, 'unknown-8bit')])