Drop dependency on async_generator

Author: Zac-HD

docs-requirements.in

@@ -10,6 +10,5 @@ towncrier != 19.9.0,!= 21.3.0
 
 # pytest-trio's own dependencies
 trio >= 0.22.0
-async_generator >= 1.9
 outcome >= 1.1.0
 pytest >= 7.2.0

docs-requirements.txt

@@ -7,9 +7,7 @@
 alabaster==0.7.12
     # via sphinx
 async-generator==1.10
-    # via
-    #   -r docs-requirements.in
-    #   trio
+    # via trio
 attrs==22.1.0
     # via
     #   -r docs-requirements.in

docs/source/quickstart.rst

@@ -93,17 +93,6 @@ And we're done! Let's try running pytest again:
    ============================== FAILURES ==============================
    __________________________ test_should_fail __________________________
 
-   value = <trio.Nursery object at 0x7f97b21fafa0>
-
-       async def yield_(value=None):
-   >       return await _yield_(value)
-
-   venv/lib/python3.8/site-packages/async_generator/_impl.py:106:
-   _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
-   venv/lib/python3.8/site-packages/async_generator/_impl.py:99: in _yield_
-       return (yield _wrap(value))
-   _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
-
        async def test_should_fail():
    >       assert False
    E       assert False
@@ -179,13 +168,6 @@ regular pytest fixture::
        # Teardown code, executed after the test is done
        await connection.execute("ROLLBACK")
 
-If you need to support Python 3.5, which doesn't allow ``yield``
-inside an ``async def`` function, then you can define async fixtures
-using the `async_generator
-<https://async-generator.readthedocs.io/en/latest/reference.html>`__
-library - just make sure to put the ``@pytest.fixture`` *above* the
-``@async_generator``.
-
 
 .. _server-fixture-example:
 

pytest.ini

@@ -1,2 +1,2 @@
-[pytest]
-addopts = -W error -ra -v --pyargs pytest_trio --verbose --cov
+[pytest]
+addopts = -W error -ra -v --pyargs pytest_trio --verbose --cov

pytest_trio/_tests/test_async_yield_fixture.py

@@ -1,40 +1,17 @@
-import sys
-import pytest
-import re
-
-
-@pytest.fixture(params=["Python>=36", "async_generator"])
-def async_yield_implementation(request):
-    if request.param == "Python>=36":
-
-        def patch_code(code):
-            # Convert code to use Python>=3.6 builtin async generator
-            code = re.sub(r"(?m)^\s*@async_generator\n", r"", code)
-            code = re.sub(r"await yield_", r"yield", code)
-            return code
-
-        return patch_code
-    else:
-        return lambda x: x
-
-
-def test_single_async_yield_fixture(testdir, async_yield_implementation):
+def test_single_async_yield_fixture(testdir):
     testdir.makepyfile(
-        async_yield_implementation(
-            """
+        """
         import pytest
         import trio
-        from async_generator import async_generator, yield_
 
         events = []
 
         @pytest.fixture
-        @async_generator
         async def fix1():
             events.append('fix1 setup')
             await trio.sleep(0)
 
-            await yield_('fix1')
+            yield 'fix1'
 
             await trio.sleep(0)
             events.append('fix1 teardown')
@@ -53,43 +30,38 @@ def test_after():
                 'fix1 teardown',
             ]
     """
-        )
     )
 
     result = testdir.runpytest()
 
     result.assert_outcomes(passed=3)
 
 
-def test_nested_async_yield_fixture(testdir, async_yield_implementation):
+def test_nested_async_yield_fixture(testdir):
 
     testdir.makepyfile(
-        async_yield_implementation(
-            """
+        """
         import pytest
         import trio
-        from async_generator import async_generator, yield_
 
         events = []
 
         @pytest.fixture
-        @async_generator
         async def fix2():
             events.append('fix2 setup')
             await trio.sleep(0)
 
-            await yield_('fix2')
+            yield 'fix2'
 
             await trio.sleep(0)
             events.append('fix2 teardown')
 
         @pytest.fixture
-        @async_generator
         async def fix1(fix2):
             events.append('fix1 setup')
             await trio.sleep(0)
 
-            await yield_('fix1')
+            yield 'fix1'
 
             await trio.sleep(0)
             events.append('fix1 teardown')
@@ -113,32 +85,28 @@ def test_after():
                 'fix2 teardown',
             ]
     """
-        )
     )
 
     result = testdir.runpytest()
 
     result.assert_outcomes(passed=3)
 
 
-def test_async_yield_fixture_within_sync_fixture(testdir, async_yield_implementation):
+def test_async_yield_fixture_within_sync_fixture(testdir):
 
     testdir.makepyfile(
-        async_yield_implementation(
-            """
+        """
         import pytest
         import trio
-        from async_generator import async_generator, yield_
 
         events = []
 
         @pytest.fixture
-        @async_generator
         async def fix2():
             events.append('fix2 setup')
             await trio.sleep(0)
 
-            await yield_('fix2')
+            yield 'fix2'
 
             await trio.sleep(0)
             events.append('fix2 teardown')
@@ -163,34 +131,28 @@ def test_after():
                 'fix2 teardown',
             ]
     """
-        )
     )
 
     result = testdir.runpytest()
 
     result.assert_outcomes(passed=3)
 
 
-def test_async_yield_fixture_within_sync_yield_fixture(
-    testdir, async_yield_implementation
-):
+def test_async_yield_fixture_within_sync_yield_fixture(testdir):
 
     testdir.makepyfile(
-        async_yield_implementation(
-            """
+        """
         import pytest
         import trio
-        from async_generator import async_generator, yield_
 
         events = []
 
         @pytest.fixture
-        @async_generator
         async def fix2():
             events.append('fix2 setup')
             await trio.sleep(0)
 
-            await yield_('fix2')
+            yield 'fix2'
 
             await trio.sleep(0)
             events.append('fix2 teardown')
@@ -220,36 +182,31 @@ def test_after():
                 'fix2 teardown',
             ]
     """
-        )
     )
 
     result = testdir.runpytest()
 
     result.assert_outcomes(passed=3)
 
 
-def test_async_yield_fixture_with_multiple_yields(testdir, async_yield_implementation):
+def test_async_yield_fixture_with_multiple_yields(testdir):
 
     testdir.makepyfile(
-        async_yield_implementation(
-            """
+        """
         import pytest
         import trio
-        from async_generator import async_generator, yield_
 
         @pytest.fixture
-        @async_generator
         async def fix1():
             await trio.sleep(0)
-            await yield_('good')
+            yield 'good'
             await trio.sleep(0)
-            await yield_('bad')
+            yield 'bad'
 
         @pytest.mark.trio
         async def test_actual_test(fix1):
             pass
     """
-        )
     )
 
     result = testdir.runpytest()
@@ -259,14 +216,12 @@ async def test_actual_test(fix1):
     result.assert_outcomes(failed=1)
 
 
-def test_async_yield_fixture_with_nursery(testdir, async_yield_implementation):
+def test_async_yield_fixture_with_nursery(testdir):
 
     testdir.makepyfile(
-        async_yield_implementation(
-            """
+        """
         import pytest
         import trio
-        from async_generator import async_generator, yield_
 
 
         async def handle_client(stream):
@@ -276,11 +231,10 @@ async def handle_client(stream):
 
 
         @pytest.fixture
-        @async_generator
         async def server():
             async with trio.open_nursery() as nursery:
                 listeners = await nursery.start(trio.serve_tcp, handle_client, 0)
-                await yield_(listeners[0])
+                yield listeners[0]
                 nursery.cancel_scope.cancel()
 
 
@@ -291,42 +245,35 @@ async def test_actual_test(server):
             rep = await stream.receive_some(4)
             assert rep == b'ping'
     """
-        )
     )
 
     result = testdir.runpytest()
 
     result.assert_outcomes(passed=1)
 
 
-def test_async_yield_fixture_crashed_teardown_allow_other_teardowns(
-    testdir, async_yield_implementation
-):
+def test_async_yield_fixture_crashed_teardown_allow_other_teardowns(testdir):
 
     testdir.makepyfile(
-        async_yield_implementation(
-            """
+        """
         import pytest
         import trio
-        from async_generator import async_generator, yield_
 
         setup_events = set()
         teardown_events = set()
 
         @pytest.fixture
-        @async_generator
         async def good_fixture():
             async with trio.open_nursery() as nursery:
                 setup_events.add('good_fixture setup')
-                await yield_(None)
+                yield None
                 teardown_events.add('good_fixture teardown')
 
         @pytest.fixture
-        @async_generator
         async def bad_fixture():
             async with trio.open_nursery() as nursery:
                 setup_events.add('bad_fixture setup')
-                await yield_(None)
+                yield None
                 teardown_events.add('bad_fixture teardown')
                 raise RuntimeError('Crash during fixture teardown')
 
@@ -348,7 +295,6 @@ def test_after():
                 'good_fixture teardown',
             }
     """
-        )
     )
 
     result = testdir.runpytest()

pytest_trio/_tests/test_fixture_mistakes.py

@@ -123,14 +123,12 @@ def test_fixture_cancels_test_but_doesnt_raise(testdir, enable_trio_mode):
         """
         import pytest
         import trio
-        from async_generator import async_generator, yield_
 
         @pytest.fixture
-        @async_generator
         async def async_fixture():
             with trio.CancelScope() as cscope:
                 cscope.cancel()
-                await yield_()
+                yield
 
 
         async def test_whatever(async_fixture):
@@ -164,4 +162,6 @@ async def test_whatever(mock_clock, extra_clock):
     result = testdir.runpytest()
 
     result.assert_outcomes(failed=1)
-    result.stdout.fnmatch_lines(["*ValueError: too many clocks spoil the broth!*"])
+    result.stdout.fnmatch_lines(
+        ["*ValueError: Expected at most one Clock in kwargs, got *"]
+    )