Use AnyIO instead of pytest-asyncio for running async tests

pyproject.toml

@@ -52,6 +52,7 @@ typing-extensions = [
 optional = true
 
 [tool.poetry.group.test.dependencies]
+anyio = { version = ">= 3.7.1" }
 pytest = [
     { version = "^8.3", python = ">=3.8" },
     { version = "^7.4", python = "<3.8" }
@@ -321,7 +322,7 @@ addopts = "--benchmark-disable"
 # Deactivate default name pattern for test classes (we use pytest_describe).
 python_classes = "PyTest*"
 # Handle all async fixtures and tests automatically by asyncio,
-asyncio_mode = "auto"
+asyncio_mode = "strict"
 # Set a timeout in seconds for aborting tests that run too long.
 timeout = "100"
 # Ignore config options not (yet) available in older Python versions.

tests/conftest.py

@@ -20,3 +20,8 @@ def pytest_collection_modifyitems(config, items):
         for item in items:
             if "slow" in item.keywords:
                 item.add_marker(skip_slow)
+
+
+@pytest.fixture
+def anyio_backend():
+    return "asyncio"

tests/execution/test_abstract.py

@@ -22,14 +22,14 @@
 
 def sync_and_async(spec):
     """Decorator for running a test synchronously and asynchronously."""
-    return pytest.mark.asyncio(
+    return pytest.mark.anyio(
         pytest.mark.parametrize("sync", [True, False], ids=("sync", "async"))(spec)
     )
 
 
 def access_variants(spec):
     """Decorator for tests with dict and object access, including inheritance."""
-    return pytest.mark.asyncio(
+    return pytest.mark.anyio(
         pytest.mark.parametrize("access", ["dict", "object", "inheritance"])(spec)
     )
 

tests/execution/test_customize.py

@@ -6,6 +6,8 @@
 from graphql.language import parse
 from graphql.type import GraphQLField, GraphQLObjectType, GraphQLSchema, GraphQLString
 
+pytestmark = pytest.mark.anyio
+
 try:
     anext  # noqa: B018
 except NameError:  # pragma: no cover (Python < 3.10)
@@ -78,7 +80,6 @@ def execute_field(
 
 
 def describe_customize_subscription():
-    @pytest.mark.asyncio
     async def uses_a_custom_subscribe_field_resolver():
         schema = GraphQLSchema(
             query=GraphQLObjectType("Query", {"foo": GraphQLField(GraphQLString)}),
@@ -107,7 +108,6 @@ async def custom_foo():
 
         await subscription.aclose()
 
-    @pytest.mark.asyncio
     async def uses_a_custom_execution_context_class():
         class TestExecutionContext(ExecutionContext):
             def __init__(self, *args, **kwargs):