Add async_callbacks() for use with async/await

Author: altendky

pytest_twisted.py

@@ -23,7 +23,11 @@ class _instances:
 
 
 def pytest_namespace():
-    return {"inlineCallbacks": inlineCallbacks, "blockon": blockon}
+    return {
+        "inlineCallbacks": inlineCallbacks,
+        "async_callbacks": async_callbacks,
+        "blockon": blockon,
+    }
 
 
 def blockon(d):
@@ -65,6 +69,11 @@ def inlineCallbacks(fun, *args, **kw):
     return defer.inlineCallbacks(fun)(*args, **kw)
 
 
+@decorator.decorator
+def async_callbacks(fun, *args, **kw):
+    return defer.ensureDeferred(fun(*args, **kw))
+
+
 def init_twisted_greenlet():
     if _instances.reactor is None or _instances.gr_twisted:
         return

testing/test_basic.py

@@ -37,6 +37,13 @@ def skip_if_reactor_not(expected_reactor):
     )
 
 
+def skip_if_no_async_await():
+    return pytest.mark.skipif(
+        sys.version_info < (3, 5),
+        reason="async/await syntax not support on Python <3.5",
+    )
+
+
 @pytest.fixture
 def cmd_opts(request):
     reactor = request.config.getoption("reactor", "default")
@@ -120,6 +127,28 @@ def test_succeed(foo):
     assert_outcomes(rr, {"passed": 2, "failed": 1})
 
 
+@skip_if_no_async_await()
+def test_async_callbacks(testdir, cmd_opts):
+    test_file = """
+    from twisted.internet import reactor, defer
+    import pytest
+    import pytest_twisted
+
+    @pytest.fixture(scope="module", params=["fs", "imap", "web"])
+    def foo(request):
+        return request.param
+
+    @pytest_twisted.async_callbacks
+    async def test_succeed(foo):
+        await defer.succeed(foo)
+        if foo == "web":
+            raise RuntimeError("baz")
+    """
+    testdir.makepyfile(test_file)
+    rr = testdir.run(sys.executable, "-m", "pytest", "-v", *cmd_opts)
+    assert_outcomes(rr, {"passed": 2, "failed": 1})
+
+
 def test_twisted_greenlet(testdir, cmd_opts):
     test_file = """
     import pytest, greenlet
@@ -165,6 +194,32 @@ def test_succeed(foo):
     assert_outcomes(rr, {"passed": 2, "failed": 1})
 
 
+@skip_if_no_async_await()
+def test_blockon_in_fixture_async(testdir, cmd_opts):
+    test_file = """
+    from twisted.internet import reactor, defer
+    import pytest
+    import pytest_twisted
+
+    @pytest.fixture(scope="module", params=["fs", "imap", "web"])
+    def foo(request):
+        d1, d2 = defer.Deferred(), defer.Deferred()
+        reactor.callLater(0.01, d1.callback, 1)
+        reactor.callLater(0.02, d2.callback, request.param)
+        pytest_twisted.blockon(d1)
+        return d2
+
+    @pytest_twisted.async_callbacks
+    async def test_succeed(foo):
+        x = await foo
+        if x == "web":
+            raise RuntimeError("baz")
+    """
+    testdir.makepyfile(test_file)
+    rr = testdir.run(sys.executable, "-m", "pytest", "-v", *cmd_opts)
+    assert_outcomes(rr, {"passed": 2, "failed": 1})
+
+
 @skip_if_reactor_not("default")
 def test_blockon_in_hook(testdir, cmd_opts):
     conftest_file = """