Test case test_write_timeout fails #191

Windows 10 Pro 1809 (Build 17763.615)
Python 3.7.2 (tags/v3.7.2:9a3ffc0492, Dec 23 2018, 22:20:52) [MSC v.1916 32 bit (Intel)] on win32

Package               Version
--------------------- ---------
appdirs               1.4.3
asn1crypto            0.24.0
atomicwrites          1.3.0
attrs                 19.1.0
autoflake             1.3
black                 19.3b0
brotlipy              0.7.0
certifi               2019.6.16
cffi                  1.12.3
chardet               3.0.4
Click                 7.0
colorama              0.4.1
coverage              4.5.4
cryptography          2.7
entrypoints           0.3
flake8                3.7.8
flake8-bugbear        19.3.0
flake8-comprehensions 2.1.0
h11                   0.8.1
h2                    3.1.1
hpack                 3.0.0
hstspreload           2019.7.31
htmlmin               0.1.12
hyperframe            5.2.0
idna                  2.8
importlib-metadata    0.19
isort                 4.3.21
Jinja2                2.10.1
jsmin                 2.2.2
livereload            2.6.1
Markdown              3.1.1
MarkupSafe            1.1.1
mccabe                0.6.1
mkdocs                1.0.4
mkdocs-material       4.4.0
mkdocs-minify-plugin  0.2.1
more-itertools        7.2.0
mypy                  0.720
mypy-extensions       0.4.1
packaging             19.1
pip                   19.0.3
pluggy                0.12.0
py                    1.8.0
pycodestyle           2.5.0
pycparser             2.19
pyflakes              2.1.1
Pygments              2.4.2
pymdown-extensions    6.0
pyparsing             2.4.2
pytest                5.0.1
pytest-asyncio        0.10.0
pytest-cov            2.7.1
PyYAML                5.1.2
rfc3986               1.3.2
setuptools            40.8.0
six                   1.12.0
toml                  0.10.0
tornado               6.0.3
trustme               0.5.2
typed-ast             1.4.0
typing-extensions     3.7.4
uvicorn               0.8.6
wcwidth               0.1.7
websockets            7.0
zipp                  0.5.2

___ test_write_timeout ___

server = <uvicorn.main.Server object at 0x03FD6290>

    @pytest.mark.asyncio
    async def test_write_timeout(server):
        timeout = TimeoutConfig(write_timeout=0.000001)
    
        async with AsyncClient(timeout=timeout) as client:
            with pytest.raises(WriteTimeout):
                data = b"*" * 1024 * 1024 * 100
>               await client.put("http://127.0.0.1:8000/slow_response", data=data)
E               Failed: DID NOT RAISE <class 'httpx.exceptions.WriteTimeout'>

tests\test_timeouts.py:30: Failed
--- Captured log setup ---
INFO     uvicorn:main.py:321 Started server process [2180]
INFO     uvicorn:main.py:381 Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
--- Captured log call ---
INFO     uvicorn:h11_impl.py:443 ('127.0.0.1', 59595) - "PUT /slow_response HTTP/1.1" 200
--- Captured log teardown ---
INFO     uvicorn:main.py:418 Shutting down
INFO     uvicorn:main.py:327 Finished server process [2180]
=== 1 failed, 236 passed in 18.31 seconds ===