Filename encoding broken for attachments in EmailMessage class

[alexey]

Message encoding broken if creating messages with EmailMessage class.

Test case:

subject = u"Тест"
body = u"Тест"
recepients = ["test@test.com"]

filename = u"тест.txt"
report = "some binary data"

email = EmailMessage(subject,body,to=recepients)
email.attach(filename.encode("utf-8"),report)
email.send()

filename will NOT be properly encoded and pushed into the message "as is". And some email clients such as MS Outlook will show broken stuff instead of filename.

[alexey]

It seems that bug is in _create_attachment method. I solved this by monkey-patching:

def _create_attachment(self, filename, content, mimetype=None):
    """
    Converts the filename, content, mimetype triple into a MIME attachment
    object.
    """
    if mimetype is None:
        mimetype, _ = mimetypes.guess_type(filename)
        if mimetype is None:
            mimetype = DEFAULT_ATTACHMENT_MIME_TYPE
    attachment = self._create_mime_attachment(content, mimetype)
    if filename:
        attachment.add_header('Content-Disposition', 'attachment',
            filename=('utf-8','',filename)) # Changed here!!! 
    return attachment

[anonymous]

Duplicate of #14964