test_ems: doc out some remaining suites

piker/data/_sampling.py

@@ -360,7 +360,10 @@ async def register_with_sampler(
                             if msg == 'broadcast_all':
                                 await Sampler.broadcast_all()
                 finally:
-                    if sub_for_broadcasts:
+                    if (
+                        sub_for_broadcasts
+                        and subs
+                    ):
                         subs.remove(stream)
             else:
                 # if no shms are passed in we just wait until cancelled

tests/test_ems.py

@@ -391,3 +391,18 @@ def test_multi_fill_positions(
                 await match_ppmsgs_on_ems_boot([ppmsg])
 
         run_and_tollerate_cancels(just_check_pp)
+
+
+def test_open_orders_reloaded(
+    open_test_pikerd: AsyncContextManager,
+    loglevel: str,
+
+    fills: tuple[dict],
+
+    check_cross_session: bool = False,
+):
+    ...
+
+
+def test_dark_order_clearing():
+    ...