test_client.py

# -*- encoding: utf-8 -*-
from collections import OrderedDict
from io import BytesIO

import mock

from hyperlink import DecodedURL, EncodedURL
from twisted.internet.defer import Deferred, succeed, CancelledError
from twisted.internet.protocol import Protocol
from twisted.python.failure import Failure
from twisted.trial.unittest import TestCase
from twisted.web.client import Agent, ResponseFailed
from twisted.web.http_headers import Headers

from treq.test.util import with_clock
from treq.client import (
    HTTPClient, _BodyBufferingProtocol, _BufferedResponse
)


class HTTPClientTests(TestCase):
    def setUp(self):
        self.agent = mock.Mock(Agent)
        self.client = HTTPClient(self.agent)

        self.fbp_patcher = mock.patch('treq.client.FileBodyProducer')
        self.FileBodyProducer = self.fbp_patcher.start()
        self.addCleanup(self.fbp_patcher.stop)

        self.mbp_patcher = mock.patch('treq.multipart.MultiPartProducer')
        self.MultiPartProducer = self.mbp_patcher.start()
        self.addCleanup(self.mbp_patcher.stop)

    def assertBody(self, expected):
        body = self.FileBodyProducer.mock_calls[0][1][0]
        self.assertEqual(body.read(), expected)

    def test_post(self):
        self.client.post('http://example.com/')
        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'accept-encoding': [b'gzip']}), None)

    def test_request_uri_idn(self):
        self.client.request('GET', u'http://č.net')
        self.agent.request.assert_called_once_with(
            b'GET', b'http://xn--bea.net',
            Headers({b'accept-encoding': [b'gzip']}), None)

    def test_request_uri_decodedurl(self):
        """
        A URL may be passed as a `hyperlink.DecodedURL` object. It is converted
        to bytes when passed to the underlying agent.
        """
        url = DecodedURL.from_text(u"https://example.org/foo")
        self.client.request("GET", url)
        self.agent.request.assert_called_once_with(
            b"GET", b"https://example.org/foo",
            Headers({b"accept-encoding": [b"gzip"]}),
            None,
        )

    def test_request_uri_encodedurl(self):
        """
        A URL may be passed as a `hyperlink.EncodedURL` object. It is converted
        to bytes when passed to the underlying agent.
        """
        url = EncodedURL.from_text(u"https://example.org/foo")
        self.client.request("GET", url)
        self.agent.request.assert_called_once_with(
            b"GET", b"https://example.org/foo",
            Headers({b"accept-encoding": [b"gzip"]}),
            None,
        )

    def test_request_uri_idn_params(self):
        """
        A URL that contains non-ASCII characters can be augmented with
        querystring parameters.

        This reproduces treq #264.
        """
        self.client.request('GET', u'http://č.net', params={'foo': 'bar'})
        self.agent.request.assert_called_once_with(
            b'GET', b'http://xn--bea.net/?foo=bar',
            Headers({b'accept-encoding': [b'gzip']}), None)

    def test_request_uri_hyperlink_params(self):
        """
        The *params* argument augments an instance of `hyperlink.DecodedURL`
        passed as the *url* parameter, just as if it were a string.
        """
        self.client.request(
            method="GET",
            url=DecodedURL.from_text(u"http://č.net"),
            params={"foo": "bar"},
        )
        self.agent.request.assert_called_once_with(
            b"GET", b"http://xn--bea.net/?foo=bar",
            Headers({b"accept-encoding": [b"gzip"]}),
            None,
        )

    def test_request_case_insensitive_methods(self):
        self.client.request('gEt', 'http://example.com/')
        self.agent.request.assert_called_once_with(
            b'GET', b'http://example.com/',
            Headers({b'accept-encoding': [b'gzip']}), None)

    def test_request_query_params(self):
        self.client.request('GET', 'http://example.com/',
                            params={'foo': ['bar']})

        self.agent.request.assert_called_once_with(
            b'GET', b'http://example.com/?foo=bar',
            Headers({b'accept-encoding': [b'gzip']}), None)

    def test_request_tuple_query_values(self):
        self.client.request('GET', 'http://example.com/',
                            params={'foo': ('bar',)})

        self.agent.request.assert_called_once_with(
            b'GET', b'http://example.com/?foo=bar',
            Headers({b'accept-encoding': [b'gzip']}), None)

    def test_request_tuple_query_value_coercion(self):
        """
        treq coerces non-string values passed to *params* like
        `urllib.urlencode()`
        """
        self.client.request('GET', 'http://example.com/', params=[
            ('text', u'A\u03a9'),
            ('text-seq', [u'A\u03a9']),
            ('bytes', [b'ascii']),
            ('bytes-seq', [b'ascii']),
            ('native', ['native']),
            ('native-seq', ['aa', 'bb']),
            ('int', 1),
            ('int-seq', (1, 2, 3)),
            ('none', None),
            ('none-seq', [None, None]),
        ])

        self.agent.request.assert_called_once_with(
            b'GET',
            (
                b'http://example.com/?'
                b'text=A%CE%A9&text-seq=A%CE%A9'
                b'&bytes=ascii&bytes-seq=ascii'
                b'&native=native&native-seq=aa&native-seq=bb'
                b'&int=1&int-seq=1&int-seq=2&int-seq=3'
                b'&none=None&none-seq=None&none-seq=None'
            ),
            Headers({b'accept-encoding': [b'gzip']}),
            None,
        )

    def test_request_tuple_query_param_coercion(self):
        """
        treq coerces non-string param names passed to *params* like
        `urllib.urlencode()`
        """
        self.client.request('GET', 'http://example.com/', params=[
            (u'text', u'A\u03a9'),
            (b'bytes', ['ascii']),
            ('native', 'native'),
            (1, 'int'),
            (None, ['none']),
        ])

        self.agent.request.assert_called_once_with(
            b'GET',
            (
                b'http://example.com/'
                b'?text=A%CE%A9&bytes=ascii'
                b'&native=native&1=int&None=none'
            ),
            Headers({b'accept-encoding': [b'gzip']}),
            None,
        )

    def test_request_query_param_seps(self):
        """
        When the characters ``&`` and ``#`` are passed to *params* as param
        names or values they are percent-escaped in the URL.

        This reproduces https://github.com/twisted/treq/issues/282
        """
        self.client.request('GET', 'http://example.com/', params=(
            ('ampersand', '&'),
            ('&', 'ampersand'),
            ('octothorpe', '#'),
            ('#', 'octothorpe'),
        ))

        self.agent.request.assert_called_once_with(
            b'GET',
            (
                b'http://example.com/'
                b'?ampersand=%26'
                b'&%26=ampersand'
                b'&octothorpe=%23'
                b'&%23=octothorpe'
            ),
            Headers({b'accept-encoding': [b'gzip']}),
            None,
        )

    def test_request_merge_query_params(self):
        self.client.request('GET', 'http://example.com/?baz=bax',
                            params={'foo': ['bar', 'baz']})

        self.agent.request.assert_called_once_with(
            b'GET', b'http://example.com/?baz=bax&foo=bar&foo=baz',
            Headers({b'accept-encoding': [b'gzip']}), None)

    def test_request_merge_tuple_query_params(self):
        self.client.request('GET', 'http://example.com/?baz=bax',
                            params=[('foo', 'bar')])

        self.agent.request.assert_called_once_with(
            b'GET', b'http://example.com/?baz=bax&foo=bar',
            Headers({b'accept-encoding': [b'gzip']}), None)

    def test_request_dict_single_value_query_params(self):
        self.client.request('GET', 'http://example.com/',
                            params={'foo': 'bar'})

        self.agent.request.assert_called_once_with(
            b'GET', b'http://example.com/?foo=bar',
            Headers({b'accept-encoding': [b'gzip']}), None)

    def test_request_data_dict(self):
        self.client.request('POST', 'http://example.com/',
                            data={'foo': ['bar', 'baz']})

        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'Content-Type': [b'application/x-www-form-urlencoded'],
                     b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)

        self.assertBody(b'foo=bar&foo=baz')

    def test_request_data_single_dict(self):
        self.client.request('POST', 'http://example.com/',
                            data={'foo': 'bar'})

        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'Content-Type': [b'application/x-www-form-urlencoded'],
                     b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)

        self.assertBody(b'foo=bar')

    def test_request_data_tuple(self):
        self.client.request('POST', 'http://example.com/',
                            data=[('foo', 'bar')])

        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'Content-Type': [b'application/x-www-form-urlencoded'],
                     b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)

        self.assertBody(b'foo=bar')

    def test_request_data_file(self):
        temp_fn = self.mktemp()

        with open(temp_fn, "wb") as temp_file:
            temp_file.write(b'hello')

        self.client.request('POST', 'http://example.com/',
                            data=open(temp_fn, 'rb'))

        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)

        self.assertBody(b'hello')

    def test_request_json_dict(self):
        self.client.request('POST', 'http://example.com/', json={'foo': 'bar'})
        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'Content-Type': [b'application/json; charset=UTF-8'],
                     b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)
        self.assertBody(b'{"foo":"bar"}')

    def test_request_json_tuple(self):
        self.client.request('POST', 'http://example.com/', json=('foo', 1))
        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'Content-Type': [b'application/json; charset=UTF-8'],
                     b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)
        self.assertBody(b'["foo",1]')

    def test_request_json_number(self):
        self.client.request('POST', 'http://example.com/', json=1.)
        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'Content-Type': [b'application/json; charset=UTF-8'],
                     b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)
        self.assertBody(b'1.0')

    def test_request_json_string(self):
        self.client.request('POST', 'http://example.com/', json='hello')
        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'Content-Type': [b'application/json; charset=UTF-8'],
                     b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)
        self.assertBody(b'"hello"')

    def test_request_json_bool(self):
        self.client.request('POST', 'http://example.com/', json=True)
        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'Content-Type': [b'application/json; charset=UTF-8'],
                     b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)
        self.assertBody(b'true')

    def test_request_json_none(self):
        self.client.request('POST', 'http://example.com/', json=None)
        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({b'Content-Type': [b'application/json; charset=UTF-8'],
                     b'accept-encoding': [b'gzip']}),
            self.FileBodyProducer.return_value)
        self.assertBody(b'null')

    @mock.patch('treq.client.uuid.uuid4', mock.Mock(return_value="heyDavid"))
    def test_request_no_name_attachment(self):

        self.client.request(
            'POST', 'http://example.com/', files={"name": BytesIO(b"hello")})

        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({
                b'accept-encoding': [b'gzip'],
                b'Content-Type': [b'multipart/form-data; boundary=heyDavid']}),
            self.MultiPartProducer.return_value)

        FP = self.FileBodyProducer.return_value
        self.assertEqual(
            mock.call(
                [('name', (None, 'application/octet-stream', FP))],
                boundary=b'heyDavid'),
            self.MultiPartProducer.call_args)

    @mock.patch('treq.client.uuid.uuid4', mock.Mock(return_value="heyDavid"))
    def test_request_named_attachment(self):

        self.client.request(
            'POST', 'http://example.com/', files={
                "name": ('image.jpg', BytesIO(b"hello"))})

        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({
                b'accept-encoding': [b'gzip'],
                b'Content-Type': [b'multipart/form-data; boundary=heyDavid']}),
            self.MultiPartProducer.return_value)

        FP = self.FileBodyProducer.return_value
        self.assertEqual(
            mock.call(
                [('name', ('image.jpg', 'image/jpeg', FP))],
                boundary=b'heyDavid'),
            self.MultiPartProducer.call_args)

    @mock.patch('treq.client.uuid.uuid4', mock.Mock(return_value="heyDavid"))
    def test_request_named_attachment_and_ctype(self):

        self.client.request(
            'POST', 'http://example.com/', files={
                "name": ('image.jpg', 'text/plain', BytesIO(b"hello"))})

        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({
                b'accept-encoding': [b'gzip'],
                b'Content-Type': [b'multipart/form-data; boundary=heyDavid']}),
            self.MultiPartProducer.return_value)

        FP = self.FileBodyProducer.return_value
        self.assertEqual(
            mock.call(
                [('name', ('image.jpg', 'text/plain', FP))],
                boundary=b'heyDavid'),
            self.MultiPartProducer.call_args)

    @mock.patch('treq.client.uuid.uuid4', mock.Mock(return_value="heyDavid"))
    def test_request_mixed_params(self):

        class NamedFile(BytesIO):
            def __init__(self, val):
                BytesIO.__init__(self, val)
                self.name = "image.png"

        self.client.request(
            'POST', 'http://example.com/',
            data=[("a", "b"), ("key", "val")],
            files=[
                ("file1", ('image.jpg', BytesIO(b"hello"))),
                ("file2", NamedFile(b"yo"))])

        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({
                b'accept-encoding': [b'gzip'],
                b'Content-Type': [b'multipart/form-data; boundary=heyDavid']}),
            self.MultiPartProducer.return_value)

        FP = self.FileBodyProducer.return_value
        self.assertEqual(
            mock.call([
                ('a', 'b'),
                ('key', 'val'),
                ('file1', ('image.jpg', 'image/jpeg', FP)),
                ('file2', ('image.png', 'image/png', FP))],
                boundary=b'heyDavid'),
            self.MultiPartProducer.call_args)

    @mock.patch('treq.client.uuid.uuid4', mock.Mock(return_value="heyDavid"))
    def test_request_mixed_params_dict(self):

        self.client.request(
            'POST', 'http://example.com/',
            data={"key": "a", "key2": "b"},
            files={"file1": BytesIO(b"hey")})

        self.agent.request.assert_called_once_with(
            b'POST', b'http://example.com/',
            Headers({
                b'accept-encoding': [b'gzip'],
                b'Content-Type': [b'multipart/form-data; boundary=heyDavid']}),
            self.MultiPartProducer.return_value)

        FP = self.FileBodyProducer.return_value
        self.assertEqual(
            mock.call([
                ('key', 'a'),
                ('key2', 'b'),
                ('file1', (None, 'application/octet-stream', FP))],
                boundary=b'heyDavid'),
            self.MultiPartProducer.call_args)

    def test_request_unsupported_params_combination(self):
        self.assertRaises(ValueError,
                          self.client.request,
                          'POST', 'http://example.com/',
                          data=BytesIO(b"yo"),
                          files={"file1": BytesIO(b"hey")})

    def test_request_json_with_data(self):
        """
        Passing `HTTPClient.request()` both *data* and *json* parameters is
        invalid because *json* is ignored. This behavior is deprecated.
        """
        self.client.request(
            "POST",
            "http://example.com/",
            data=BytesIO(b"..."),
            json=None,  # NB: None is a valid value. It encodes to b'null'.
        )

        [w] = self.flushWarnings([self.test_request_json_with_data])
        self.assertEqual(DeprecationWarning, w["category"])
        self.assertEqual(
            (
                "Argument 'json' will be ignored because 'data' was also passed."
                " This will raise TypeError in the next treq release."
            ),
            w['message'],
        )

    def test_request_json_with_files(self):
        """
        Passing `HTTPClient.request()` both *files* and *json* parameters is
        invalid because *json* is ignored. This behavior is deprecated.
        """
        self.client.request(
            "POST",
            "http://example.com/",
            files={"f1": ("foo.txt", "text/plain", BytesIO(b"...\n"))},
            json=["this is ignored"],
        )

        [w] = self.flushWarnings([self.test_request_json_with_files])
        self.assertEqual(DeprecationWarning, w["category"])
        self.assertEqual(
            (
                "Argument 'json' will be ignored because 'files' was also passed."
                " This will raise TypeError in the next treq release."
            ),
            w['message'],
        )

    def test_request_dict_headers(self):
        self.client.request('GET', 'http://example.com/', headers={
            'User-Agent': 'treq/0.1dev',
            'Accept': ['application/json', 'text/plain']
        })

        self.agent.request.assert_called_once_with(
            b'GET', b'http://example.com/',
            Headers({b'User-Agent': [b'treq/0.1dev'],
                     b'accept-encoding': [b'gzip'],
                     b'Accept': [b'application/json', b'text/plain']}),
            None)

    def test_request_headers_invalid_type(self):
        """
        `HTTPClient.request()` warns that headers of an unexpected type are
        invalid and that this behavior is deprecated.
        """
        self.client.request('GET', 'http://example.com', headers=[])

        [w] = self.flushWarnings([self.test_request_headers_invalid_type])
        self.assertEqual(DeprecationWarning, w['category'])
        self.assertIn(
            "headers must be a dict, twisted.web.http_headers.Headers, or None,",
            w['message'],
        )

    def test_request_dict_headers_invalid_values(self):
        """
        `HTTPClient.request()` warns that non-string header values are dropped
        and that this behavior is deprecated.
        """
        self.client.request('GET', 'http://example.com', headers=OrderedDict([
            ('none', None),
            ('one', 1),
            ('ok', 'string'),
        ]))

        [w1, w2] = self.flushWarnings([self.test_request_dict_headers_invalid_values])
        self.assertEqual(DeprecationWarning, w1['category'])
        self.assertEqual(DeprecationWarning, w2['category'])
        self.assertIn(
            "The value of headers key 'none' has non-string type",
            w1['message'],
        )
        self.assertIn(
            "The value of headers key 'one' has non-string type",
            w2['message'],
        )

    def test_request_invalid_param(self):
        """
        `HTTPClient.request()` warns that invalid parameters are ignored and
        that this is deprecated.
        """
        self.client.request('GET', b'http://example.com', invalid=True)

        [w] = self.flushWarnings([self.test_request_invalid_param])
        self.assertEqual(
            (
                "Got unexpected keyword argument: 'invalid'."
                " treq will ignore this argument,"
                " but will raise TypeError in the next treq release."
            ),
            w['message'],
        )

    @with_clock
    def test_request_timeout_fired(self, clock):
        """
        Verify the request is cancelled if a response is not received
        within specified timeout period.
        """
        self.agent.request.return_value = d = Deferred()
        self.client.request('GET', 'http://example.com', timeout=2)

        # simulate we haven't gotten a response within timeout seconds
        clock.advance(3)

        # a deferred should have been cancelled
        self.failureResultOf(d, CancelledError)

    @with_clock
    def test_request_timeout_cancelled(self, clock):
        """
        Verify timeout is cancelled if a response is received before
        timeout period elapses.
        """
        self.agent.request.return_value = d = Deferred()
        self.client.request('GET', 'http://example.com', timeout=2)

        # simulate a response
        d.callback(mock.Mock(code=200, headers=Headers({})))

        # now advance the clock but since we already got a result,
        # a cancellation timer should have been cancelled
        clock.advance(3)

        self.successResultOf(d)

    def test_response_is_buffered(self):
        response = mock.Mock(deliverBody=mock.Mock(),
                             headers=Headers({}))

        self.agent.request.return_value = succeed(response)

        d = self.client.get('http://www.example.com')

        result = self.successResultOf(d)

        protocol = mock.Mock(Protocol)
        result.deliverBody(protocol)
        self.assertEqual(response.deliverBody.call_count, 1)

        result.deliverBody(protocol)
        self.assertEqual(response.deliverBody.call_count, 1)

    def test_response_buffering_is_disabled_with_unbufferred_arg(self):
        response = mock.Mock(headers=Headers({}))

        self.agent.request.return_value = succeed(response)

        d = self.client.get('http://www.example.com', unbuffered=True)

        # YOLO public attribute.
        self.assertEqual(self.successResultOf(d).original, response)

    def test_request_post_redirect_denied(self):
        response = mock.Mock(code=302, headers=Headers({'Location': ['/']}))
        self.agent.request.return_value = succeed(response)
        d = self.client.post('http://www.example.com')
        self.failureResultOf(d, ResponseFailed)

    def test_request_browser_like_redirects(self):
        response = mock.Mock(code=302, headers=Headers({'Location': ['/']}))

        self.agent.request.return_value = succeed(response)

        raw = mock.Mock(return_value=[])
        final_resp = mock.Mock(code=200, headers=mock.Mock(getRawHeaders=raw))
        with mock.patch('twisted.web.client.RedirectAgent._handleRedirect',
                        return_value=final_resp):
            d = self.client.post('http://www.google.com',
                                 browser_like_redirects=True,
                                 unbuffered=True)

        self.assertEqual(self.successResultOf(d).original, final_resp)


class BodyBufferingProtocolTests(TestCase):
    def test_buffers_data(self):
        buffer = []
        protocol = _BodyBufferingProtocol(
            mock.Mock(Protocol),
            buffer,
            None
        )

        protocol.dataReceived("foo")
        self.assertEqual(buffer, ["foo"])

        protocol.dataReceived("bar")
        self.assertEqual(buffer, ["foo", "bar"])

    def test_propagates_data_to_destination(self):
        destination = mock.Mock(Protocol)
        protocol = _BodyBufferingProtocol(
            destination,
            [],
            None
        )

        protocol.dataReceived(b"foo")
        destination.dataReceived.assert_called_once_with(b"foo")

        protocol.dataReceived(b"bar")
        destination.dataReceived.assert_called_with(b"bar")

    def test_fires_finished_deferred(self):
        finished = Deferred()
        protocol = _BodyBufferingProtocol(
            mock.Mock(Protocol),
            [],
            finished
        )

        class TestResponseDone(Exception):
            pass

        protocol.connectionLost(TestResponseDone())

        self.failureResultOf(finished, TestResponseDone)

    def test_propogates_connectionLost_reason(self):
        destination = mock.Mock(Protocol)
        protocol = _BodyBufferingProtocol(
            destination,
            [],
            Deferred().addErrback(lambda ign: None)
        )

        class TestResponseDone(Exception):
            pass

        reason = TestResponseDone()
        protocol.connectionLost(reason)
        destination.connectionLost.assert_called_once_with(reason)


class BufferedResponseTests(TestCase):
    def test_wraps_protocol(self):
        wrappers = []
        wrapped = mock.Mock(Protocol)
        response = mock.Mock(deliverBody=mock.Mock(wraps=wrappers.append))

        br = _BufferedResponse(response)

        br.deliverBody(wrapped)
        response.deliverBody.assert_called_once_with(wrappers[0])
        self.assertNotEqual(wrapped, wrappers[0])

    def test_concurrent_receivers(self):
        wrappers = []
        wrapped = mock.Mock(Protocol)
        unwrapped = mock.Mock(Protocol)
        response = mock.Mock(deliverBody=mock.Mock(wraps=wrappers.append))

        br = _BufferedResponse(response)

        br.deliverBody(wrapped)
        br.deliverBody(unwrapped)
        response.deliverBody.assert_called_once_with(wrappers[0])

        wrappers[0].dataReceived(b"foo")
        wrapped.dataReceived.assert_called_once_with(b"foo")

        self.assertEqual(unwrapped.dataReceived.call_count, 0)

        class TestResponseDone(Exception):
            pass

        done = Failure(TestResponseDone())

        wrappers[0].connectionLost(done)
        wrapped.connectionLost.assert_called_once_with(done)
        unwrapped.dataReceived.assert_called_once_with(b"foo")
        unwrapped.connectionLost.assert_called_once_with(done)

    def test_receiver_after_finished(self):
        wrappers = []
        finished = mock.Mock(Protocol)

        response = mock.Mock(deliverBody=mock.Mock(wraps=wrappers.append))

        br = _BufferedResponse(response)
        br.deliverBody(mock.Mock(Protocol))
        wrappers[0].dataReceived(b"foo")

        class TestResponseDone(Exception):
            pass

        done = Failure(TestResponseDone())

        wrappers[0].connectionLost(done)

        br.deliverBody(finished)

        finished.dataReceived.assert_called_once_with(b"foo")
        finished.connectionLost.assert_called_once_with(done)