get tests to pass on python 3.10

Resolved various deprecation warnings which were appearing as of Python
version 3.10.0b1.

block aiomysql on python 3.10 as they are using the "loop" argument
that's removed

sqlcipher-binary has no builds on 3.10, block it for 3.10

Fixes: #6540
Fixes: #6543
Change-Id: Iec1e3881fb289878881ae043b1a18c3ecdf5f077

1 files changed, 18 insertions, 3 deletions

diff --git a/lib/sqlalchemy/util/_concurrency_py3k.py b/lib/sqlalchemy/util/_concurrency_py3k.py
index 5f03972b2..3b60e6584 100644
--- a/lib/sqlalchemy/util/_concurrency_py3k.py
+++ b/lib/sqlalchemy/util/_concurrency_py3k.py
@@ -74,7 +74,7 @@ def await_fallback(awaitable: Coroutine) -> Any:
     # this is called in the context greenlet while running fn
     current = greenlet.getcurrent()
     if not isinstance(current, _AsyncIoGreenlet):
-        loop = asyncio.get_event_loop()
+        loop = get_event_loop()
         if loop.is_running():
             raise exc.MissingGreenlet(
                 "greenlet_spawn has not been called and asyncio event "
@@ -152,7 +152,7 @@ class AsyncAdaptedLock:
 def _util_async_run_coroutine_function(fn, *args, **kwargs):
     """for test suite/ util only"""
 
-    loop = asyncio.get_event_loop()
+    loop = get_event_loop()
     if loop.is_running():
         raise Exception(
             "for async run coroutine we expect that no greenlet or event "
@@ -164,10 +164,25 @@ def _util_async_run_coroutine_function(fn, *args, **kwargs):
 def _util_async_run(fn, *args, **kwargs):
     """for test suite/ util only"""
 
-    loop = asyncio.get_event_loop()
+    loop = get_event_loop()
     if not loop.is_running():
         return loop.run_until_complete(greenlet_spawn(fn, *args, **kwargs))
     else:
         # allow for a wrapped test function to call another
         assert isinstance(greenlet.getcurrent(), _AsyncIoGreenlet)
         return fn(*args, **kwargs)
+
+
+def get_event_loop():
+    """vendor asyncio.get_event_loop() for python 3.7 and above.
+
+    Python 3.10 deprecates get_event_loop() as a standalone.
+
+    """
+    if compat.py37:
+        try:
+            return asyncio.get_running_loop()
+        except RuntimeError:
+            return asyncio.get_event_loop_policy().get_event_loop()
+    else:
+        return asyncio.get_event_loop()