def testMultipartEncoding(self):
    # This is really a table test for various issues we've seen in
    # the past; see notes below for particular histories.

    test_cases = [
        # Python's mime module by default encodes lines that start
        # with "From " as ">From ", which we need to make sure we
        # don't run afoul of when sending content that isn't
        # intended to be so encoded. This test calls out that we
        # get this right. We test for both the multipart and
        # non-multipart case.
        'line one\nFrom \nline two',

        # We had originally used a `six.StringIO` to hold the http
        # request body in the case of a multipart upload; for
        # bytes being uploaded in Python3, however, this causes
        # issues like this:
        # https://github.com/GoogleCloudPlatform/gcloud-python/issues/1760
        # We test below to ensure that we don't end up mangling
        # the body before sending.
        u'name,main_ingredient\nRäksmörgås,Räkor\nBaguette,Bröd',
    ]

    for upload_contents in test_cases:
        multipart_body = '{"body_field_one": 7}'
        upload_bytes = upload_contents.encode('ascii', 'backslashreplace')
        upload_config = base_api.ApiUploadInfo(
            accept=['*/*'],
            max_size=None,
            resumable_multipart=True,
            resumable_path=u'/resumable/upload',
            simple_multipart=True,
            simple_path=u'/upload',
        )
        url_builder = base_api._UrlBuilder('http://www.uploads.com')

        # Test multipart: having a body argument in http_request forces
        # multipart here.
        upload = transfer.Upload.FromStream(
            six.BytesIO(upload_bytes),
            'text/plain',
            total_size=len(upload_bytes))
        http_request = http_wrapper.Request(
            'http://www.uploads.com',
            headers={'content-type': 'text/plain'},
            body=multipart_body)
        upload.ConfigureRequest(upload_config, http_request, url_builder)
        self.assertEqual(
            'multipart', url_builder.query_params['uploadType'])
        rewritten_upload_contents = b'\n'.join(
            http_request.body.split(b'--')[2].splitlines()[1:])
        self.assertTrue(rewritten_upload_contents.endswith(upload_bytes))

        # Test non-multipart (aka media): no body argument means this is
        # sent as media.
        upload = transfer.Upload.FromStream(
            six.BytesIO(upload_bytes),
            'text/plain',
            total_size=len(upload_bytes))
        http_request = http_wrapper.Request(
            'http://www.uploads.com',
            headers={'content-type': 'text/plain'})
        upload.ConfigureRequest(upload_config, http_request, url_builder)
        self.assertEqual(url_builder.query_params['uploadType'], 'media')
        rewritten_upload_contents = http_request.body
        self.assertTrue(rewritten_upload_contents.endswith(upload_bytes))