Stop provider tests leaking AF2 global TI session (#73272)

devel-common/src/tests_common/pytest_plugin.py

@@ -2147,6 +2147,26 @@ def reset_team_name_cache():
         clear_team_name_cache()
 
 
+@pytest.fixture(autouse=True)
+def clear_current_task_instance_session():
+    """Reset the process global taskinstance session between tests.
+
+    Reaching it outside a task run leaves it set, and every later ``ti.run()`` in the process
+    then raises "Session already set for this task". No-op on Airflow 3.
+    """
+    try:
+        import airflow.utils.task_instance_session as task_instance_session
+    except ModuleNotFoundError:
+        yield
+        return
+
+    task_instance_session.__current_task_instance_session = None
+    try:
+        yield
+    finally:
+        task_instance_session.__current_task_instance_session = None
+
+
 @pytest.fixture(autouse=True)
 def refuse_to_run_test_from_wrongly_named_files(request: pytest.FixtureRequest):
     filepath = request.node.path

providers/standard/tests/unit/standard/decorators/test_python.py

@@ -86,15 +86,6 @@ PY38 = sys.version_info >= (3, 8)
 PY311 = sys.version_info >= (3, 11)
 
 
-@pytest.fixture(autouse=True)
-def clear_current_task_session():
-    try:
-        import airflow.utils.task_instance_session
-    except ModuleNotFoundError:
-        return
-    airflow.utils.task_instance_session.__current_task_instance_session = None
-
-
 class TestAirflowTaskDecorator(BasePythonTest):
     default_date = DEFAULT_DATE