Add missing truncate() call on BytesIO object

[toudi]

When subsequent payload to be pushed by mocket was shorter than previous one, additional data were dumped. This was because BytesIO object had longer length; calling truncate() on the BytesIO object solves this problem

code to reproduce the problem, before this patch:

@mocketize
def test_something():
    Mocket.register(
        MocketEntry(
            ('example.com', 80),
            [
                b'this is some long payload'
                b'short',
            ]
        ),
    )

then, when one would use socket object, and call recv on it, one would get part of the first payload with the second call

[coveralls]

Coverage increased (+0.002%) to 99.101% when pulling ea61139 on toudi:add-missing-truncate-call into 53cc4cf on mindflayer:master.

[toudi]

I don't know why travis build is failing on 3.7

output from my own py.test:

platform linux -- Python 3.7.0a0, pytest-3.0.7, py-1.4.33, pluggy-0.4.0 -- /home/toudi/.pyenv/versions/3.7-dev/bin/python3.7
cachedir: .cache
rootdir: /home/toudi/projects/prywatne/python-mocket, inifile: setup.cfg
plugins: cov-2.4.0
collected 14 items 

tests/main/test_http.py::TrueHttpEntryTestCase::test_truesendall PASSED
tests/main/test_http.py::TrueHttpEntryTestCase::test_truesendall_with_chunk_recording PASSED
tests/main/test_http.py::TrueHttpEntryTestCase::test_truesendall_with_dump_from_recording PASSED
tests/main/test_http.py::TrueHttpEntryTestCase::test_truesendall_with_gzip_recording PASSED
tests/main/test_http.py::TrueHttpEntryTestCase::test_truesendall_with_recording PASSED
tests/main/test_http.py::TrueHttpEntryTestCase::test_wrongpath_truesendall PASSED
tests/main/test_http.py::HttpEntryTestCase::test_file_object PASSED
tests/main/test_http.py::HttpEntryTestCase::test_multipart PASSED
tests/main/test_http.py::HttpEntryTestCase::test_register PASSED
tests/main/test_http.py::HttpEntryTestCase::test_request_bodies PASSED
tests/main/test_http.py::HttpEntryTestCase::test_same_url_different_methods PASSED
tests/main/test_http.py::HttpEntryTestCase::test_sendall PASSED
tests/main/test_http.py::HttpEntryTestCase::test_sendall_double PASSED
tests/main/test_http.py::HttpEntryTestCase::test_sendall_json PASSED

----------- coverage: platform linux, python 3.7.0-alpha-0 -----------
Name                                 Stmts   Miss  Cover   Missing
------------------------------------------------------------------
mocket/__init__.py                       4      0   100%
mocket/mocket.py                       266     30    89%   59, 66-78, 84, 88, 91, 124, 141, 144-148, 170-172, 206, 326-327, 379, 389, 394-396, 404, 435
mocket/mockhttp.py                      84      1    99%   75
mocket/mockredis.py                     48     48     0%   2-77
mocket/plugins/__init__.py               0      0   100%
mocket/plugins/pook_mock_engine.py      43     43     0%   1-65
------------------------------------------------------------------
TOTAL                                  445    122    73%

[mindflayer]

Thank you so much for your contribution. I have no idea on why this is failing but I'm sure I've seen the error before, and I am still not able to reproduce it.

[mindflayer]

@toudi are you actively using mocket? If so, in which way? Feel free to point me to a public repo, if this is the case.

[toudi]

@mindflayer I am writing unit tests for websocket library => https://github.com/wildfoundry/dataplicity-lomond

how can I download new version from pypi ?

[mindflayer]

You mean you'd like to install a new version with your patch?

[toudi]

well, I thought this was the whole point of patching code :D otherwise I would have to point tox / pytest to github repo

[mindflayer]

It is and I really appreciated that, but please give me the time to actually do it. I'm working at it while I'm attending DjangoCon. :P

[toudi]

lol, no problem ;)

[mindflayer]

Enjoy it!
https://pypi.python.org/pypi/mocket/1.8.1