Use `collapse_eg()` in broadcaster suite

Around the test embedded `trio.open_nursery()` calls as expected. Also
tidy up the various nursery var names.

tests/test_task_broadcasting.py

@@ -2,7 +2,9 @@
 Broadcast channels for fan-out to local tasks.
 
 """
-from contextlib import asynccontextmanager
+from contextlib import (
+    asynccontextmanager as acm,
+)
 from functools import partial
 from itertools import cycle
 import time
@@ -15,6 +17,7 @@ import tractor
 from tractor.trionics import (
     broadcast_receiver,
     Lagged,
+    collapse_eg,
 )
 
 
@@ -62,7 +65,7 @@ async def ensure_sequence(
                 break
 
 
-@asynccontextmanager
+@acm
 async def open_sequence_streamer(
 
     sequence: list[int],
@@ -74,9 +77,9 @@ async def open_sequence_streamer(
     async with tractor.open_nursery(
         arbiter_addr=reg_addr,
         start_method=start_method,
-    ) as tn:
+    ) as an:
 
-        portal = await tn.start_actor(
+        portal = await an.start_actor(
             'sequence_echoer',
             enable_modules=[__name__],
         )
@@ -155,9 +158,12 @@ def test_consumer_and_parent_maybe_lag(
         ) as stream:
 
             try:
-                async with trio.open_nursery() as n:
+                async with (
+                    collapse_eg(),
+                    trio.open_nursery() as tn,
+                ):
 
-                    n.start_soon(
+                    tn.start_soon(
                         ensure_sequence,
                         stream,
                         sequence.copy(),
@@ -230,8 +236,8 @@ def test_faster_task_to_recv_is_cancelled_by_slower(
 
         ) as stream:
 
-            async with trio.open_nursery() as n:
-                n.start_soon(
+            async with trio.open_nursery() as tn:
+                tn.start_soon(
                     ensure_sequence,
                     stream,
                     sequence.copy(),
@@ -253,7 +259,7 @@ def test_faster_task_to_recv_is_cancelled_by_slower(
                         continue
 
                 print('cancelling faster subtask')
-                n.cancel_scope.cancel()
+                tn.cancel_scope.cancel()
 
             try:
                 value = await stream.receive()
@@ -371,13 +377,13 @@ def test_ensure_slow_consumers_lag_out(
                                     f'on {lags}:{value}')
                                 return
 
-            async with trio.open_nursery() as nursery:
+            async with trio.open_nursery() as tn:
 
                 for i in range(1, num_laggers):
 
                     task_name = f'sub_{i}'
                     laggers[task_name] = 0
-                    nursery.start_soon(
+                    tn.start_soon(
                         partial(
                             sub_and_print,
                             delay=i*0.001,
@@ -497,6 +503,7 @@ def test_no_raise_on_lag():
                 # internals when the no raise flag is set.
                 loglevel='warning',
             ),
+            collapse_eg(),
             trio.open_nursery() as n,
         ):
             n.start_soon(slow)

tractor/trionics/_beg.py

@@ -20,7 +20,6 @@ first-class-`trio` from a historical perspective B)
 
 '''
 from contextlib import (
-    # bontextmanager as cm,
     asynccontextmanager as acm,
 )