Merge pull request #62 from agronholm/async_generator

Added support for the async_generator library

Author: Tinche

README.rst

@@ -114,7 +114,7 @@ Async fixtures
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Asynchronous fixtures are defined just like ordinary pytest fixtures, except they should be coroutines or asynchronous generators.
 
-.. code-block:: python
+.. code-block:: python3
 
     @pytest.fixture
     async def async_gen_fixture():
@@ -130,6 +130,20 @@ to redefine the ``event_loop`` fixture to have the same or broader scope.
 Async fixtures need the event loop, and so must have the same or narrower scope
 than the ``event_loop`` fixture.
 
+If you want to do this with Python 3.5, the ``yield`` statement must be replaced with ``await yield_()`` and the coroutine
+function must be decorated with ``@async_generator``, like so:
+
+.. code-block:: python3
+
+    from async_generator import yield_, async_generator
+
+    @pytest.fixture
+    @async_generator
+    async def async_gen_fixture():
+        await asyncio.sleep(0.1)
+        await yield_('a value')
+
+
 Markers
 -------
 

pytest_asyncio/plugin.py

@@ -3,25 +3,22 @@
 import contextlib
 import inspect
 import socket
-import sys
 from concurrent.futures import ProcessPoolExecutor
 
 import pytest
 from _pytest.python import transfer_markers
 
+try:
+    from async_generator import isasyncgenfunction
+except ImportError:
+    from inspect import isasyncgenfunction
+
 
 def _is_coroutine(obj):
     """Check to see if an object is really an asyncio coroutine."""
     return asyncio.iscoroutinefunction(obj) or inspect.isgeneratorfunction(obj)
 
 
-if sys.version_info[:2] < (3, 6):
-    def isasyncgenfunction(_):
-        return False
-else:
-    from inspect import isasyncgenfunction
-
-
 def pytest_configure(config):
     """Inject documentation."""
     config.addinivalue_line("markers",

setup.py

@@ -43,7 +43,10 @@ def find_version(*file_paths):
     install_requires=[
         'pytest >= 3.0.6',
     ],
+    extras_require={
+        ':python_version == "3.5"': 'async_generator >= 1.3'
+    },
     entry_points={
         'pytest11': ['asyncio = pytest_asyncio.plugin'],
-    },
+    }
 )

test_requirements.txt

@@ -1,2 +1,3 @@
 coverage==4.1
-tox==2.5.0
+tox==2.5.0
+async_generator==1.8

tests/async_fixtures/test_async_gen_fixtures_35.py

@@ -0,0 +1,40 @@
+import unittest.mock
+
+import pytest
+from async_generator import yield_, async_generator
+
+START = object()
+END = object()
+RETVAL = object()
+
+
+@pytest.fixture(scope='module')
+def mock():
+    return unittest.mock.Mock(return_value=RETVAL)
+
+
+@pytest.fixture
+@async_generator
+async def async_gen_fixture(mock):
+    try:
+        await yield_(mock(START))
+    except Exception as e:
+        mock(e)
+    else:
+        mock(END)
+
+
+@pytest.mark.asyncio
+async def test_async_gen_fixture(async_gen_fixture, mock):
+    assert mock.called
+    assert mock.call_args_list[-1] == unittest.mock.call(START)
+    assert async_gen_fixture is RETVAL
+
+
+@pytest.mark.asyncio
+async def test_async_gen_fixture_finalized(mock):
+    try:
+        assert mock.called
+        assert mock.call_args_list[-1] == unittest.mock.call(END)
+    finally:
+        mock.reset_mock()