From 3e74761b76f337bf0e36dcdbdd7fdc0dd814105b Mon Sep 17 00:00:00 2001
From: "Tom C (DLS)" <101418278+coretl@users.noreply.github.com>
Date: Wed, 16 Oct 2024 17:14:08 +0100
Subject: [PATCH 1/2] with DeviceCollector doesn't work in plans, so error
 rather than hang (#612)

---
 src/ophyd_async/core/_device.py     |  7 ++++++-
 tests/core/test_device_collector.py | 10 ++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/ophyd_async/core/_device.py b/src/ophyd_async/core/_device.py
index b4305c2bfa..bf3e23f5d6 100644
--- a/src/ophyd_async/core/_device.py
+++ b/src/ophyd_async/core/_device.py
@@ -12,7 +12,7 @@
 )
 
 from bluesky.protocols import HasName
-from bluesky.run_engine import call_in_bluesky_event_loop
+from bluesky.run_engine import call_in_bluesky_event_loop, in_bluesky_event_loop
 
 from ._utils import DEFAULT_TIMEOUT, NotConnected, wait_for_connection
 
@@ -224,6 +224,11 @@ async def __aexit__(self, type, value, traceback):
         await self._on_exit()
 
     def __exit__(self, type_, value, traceback):
+        if in_bluesky_event_loop():
+            raise RuntimeError(
+                "Cannot use DeviceConnector inside a plan, instead use "
+                "`yield from ophyd_async.plan_stubs.ensure_connected(device)`"
+            )
         self._objects_on_exit = self._caller_locals()
         try:
             fut = call_in_bluesky_event_loop(self._on_exit())
diff --git a/tests/core/test_device_collector.py b/tests/core/test_device_collector.py
index efebc6a48f..cdb6e122c5 100644
--- a/tests/core/test_device_collector.py
+++ b/tests/core/test_device_collector.py
@@ -67,6 +67,16 @@ def test_sync_device_connector_run_engine_created_connects(RE):
     assert working_device.connected
 
 
+def test_connecting_in_plan_raises(RE):
+    def bad_plan():
+        yield from bps.null()
+        with DeviceCollector():
+            working_device = WorkingDevice("somename")  # noqa: F841
+
+    with pytest.raises(RuntimeError, match="Cannot use DeviceConnector inside a plan"):
+        RE(bad_plan())
+
+
 def test_async_device_connector_run_engine_same_event_loop():
     async def set_up_device():
         async with DeviceCollector(mock=True):

From c91d2831d95df8c8f23e85f7f18686362f5e8922 Mon Sep 17 00:00:00 2001
From: Dominic Oram <dominic.oram@diamond.ac.uk>
Date: Tue, 29 Oct 2024 13:45:17 +0000
Subject: [PATCH 2/2] Add test for context race condition (#600)

* Add test for context race condition

* Add timeout to wait on connection in test
---
 tests/epics/signal/test_signals.py | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/tests/epics/signal/test_signals.py b/tests/epics/signal/test_signals.py
index e2e5c20f7d..0ce7fd6b45 100644
--- a/tests/epics/signal/test_signals.py
+++ b/tests/epics/signal/test_signals.py
@@ -14,12 +14,15 @@
 from typing import Any, Literal
 from unittest.mock import ANY
 
+import bluesky.plan_stubs as bps
 import numpy as np
 import numpy.typing as npt
 import pytest
 from aioca import CANothing, purge_channel_caches
 from bluesky.protocols import Reading
+from bluesky.run_engine import RunEngine
 from event_model import DataKey
+from ophyd.signal import EpicsSignal
 from typing_extensions import TypedDict
 
 from ophyd_async.core import (
@@ -917,3 +920,21 @@ async def test_signals_created_for_not_prec_0_float_cannot_use_int(ioc: IOC):
         TypeError, match=f"{ioc.protocol}:float_prec_1 has type float not int"
     ):
         await sig.connect()
+
+
+async def test_can_read_using_ophyd_async_then_ophyd(ioc: IOC):
+    oa_read = f"{ioc.protocol}://{PV_PREFIX}:{ioc.protocol}:float_prec_1"
+    ophyd_read = f"{PV_PREFIX}:{ioc.protocol}:float_prec_0"
+
+    ophyd_async_sig = epics_signal_rw(float, oa_read)
+    await ophyd_async_sig.connect()
+    ophyd_signal = EpicsSignal(ophyd_read)
+    ophyd_signal.wait_for_connection(timeout=5)
+
+    RE = RunEngine()
+
+    def my_plan():
+        yield from bps.rd(ophyd_async_sig)
+        yield from bps.rd(ophyd_signal)
+
+    RE(my_plan())