From 568902a5a94754d87df4bb25ac55066b3bf107e8 Mon Sep 17 00:00:00 2001 From: Tyler Goodlet Date: Sun, 28 Nov 2021 18:51:34 -0500 Subject: [PATCH] Add test for #265: "msg sent before stream opened" This always triggered the mentioned race condition. We need to figure out the best approach to avoid this case. --- tests/test_context_streams.py | 54 +++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 tests/test_context_streams.py diff --git a/tests/test_context_streams.py b/tests/test_context_streams.py new file mode 100644 index 0000000..3d00564 --- /dev/null +++ b/tests/test_context_streams.py @@ -0,0 +1,54 @@ +''' +``async with ():`` inlined context-stream cancellation testing. + +Verify the we raise errors when streams are opened prior to sync-opening +a ``tractor.Context`` beforehand. + +''' +import trio +from trio.lowlevel import current_task +import tractor + + +@tractor.context +async def never_open_stream( + + ctx: tractor.Context, + +) -> None: + '''Bidir streaming endpoint which will stream + back any sequence it is sent item-wise. + + ''' + await ctx.started() + await trio.sleep_forever() + + +def test_no_far_end_stream_opened(): + ''' + This should exemplify the bug from: + https://github.com/goodboy/tractor/issues/265 + + ''' + async def main(): + async with tractor.open_nursery() as n: + portal = await n.start_actor( + 'starts_no_stream', + enable_modules=[__name__], + ) + + async with ( + portal.open_context( + never_open_stream,) as (ctx, sent), + ctx.open_stream() as stream, + ): + assert sent is None + + # XXX: so the question is whether + # this should error if the far end + # has not yet called `ctx.open_stream()`? + # If we decide to do that we need a synchronization + # message which is sent from that call? + await stream.send('yo') + + trio.run(main)