Fix `spawn` fixture cleanup + test assertions

Improve the `spawn` fixture teardown logic in
`tests/devx/conftest.py` fixing the while-else bug, and fix
`test_advanced_faults` genexp for `TransportClosed` exc type
checking.

Deats,
- replace broken `while-else` pattern with direct
  `if ptyproc.isalive()` check after the SIGINT loop.
- fix undefined `spawned` ref -> `ptyproc.isalive()` in
  while condition.
- improve walrus expr formatting in timeout check (multiline
  style).

Also fix `test_ipc_channel_break_during_stream()` assertion,
- wrap genexp in `all()` call so it actually checks all excs
  are `TransportClosed` instead of just creating an unused
  generator.

(this patch was suggested by copilot in,
 https://github.com/goodboy/tractor/pull/411)

(this commit msg was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code

tests/devx/conftest.py

@@ -101,15 +101,18 @@ def spawn(
         start: float = time.time()
         timeout: float = 5
         while (
-            spawned
+            ptyproc.isalive()
             and
-            spawned.isalive()
+            (
-            and
+                (_time_took := (time.time() - start))
-            (_time_took := (time.time() - start) < timeout)
+                 <
+                 timeout
+            )
         ):
             ptyproc.kill(signal.SIGINT)
             time.sleep(0.01)
-        else:
+
+        if ptyproc.isalive():
             ptyproc.kill(signal.SIGKILL)
 
     # TODO? ensure we've cleaned up any UDS-paths?

tests/test_advanced_faults.py

@@ -255,8 +255,10 @@ def test_ipc_channel_break_during_stream(
         assert (
             len(excs) <= 2
             and
-            (isinstance(exc, TransportClosed)
+            all(
-             for exc in excs)
+                isinstance(exc, TransportClosed)
+                for exc in excs
+            )
         )
         final_exc = excs[0]
         assert isinstance(final_exc, expect_final_exc)

tractor/_rpc.py

@@ -284,9 +284,14 @@ async def _errors_relayed_via_ipc(
     try:
         yield  # run RPC invoke body
 
-    except TransportClosed:
+    # NOTE, never REPL any pseudo-expected tpt-disconnect.
-        log.exception('Tpt disconnect during remote-exc relay?')
+    except TransportClosed as err:
-        raise
+        rpc_err = err
+        log.warning(
+            f'Tpt disconnect during remote-exc relay due to,\n'
+            f'{err!r}\n'
+        )
+        raise err
 
     # box and ship RPC errors for wire-transit via
     # the task's requesting parent IPC-channel.
@@ -323,9 +328,6 @@ async def _errors_relayed_via_ipc(
                         and debug_kbis
                     )
                 )
-                # TODO? better then `debug_filter` below?
-                and
-                not isinstance(err, TransportClosed)
             ):
                 # XXX QUESTION XXX: is there any case where we'll
                 # want to debug IPC disconnects as a default?
@@ -346,13 +348,6 @@ async def _errors_relayed_via_ipc(
                 entered_debug = await debug._maybe_enter_pm(
                     err,
                     api_frame=inspect.currentframe(),
-
-                    # don't REPL any psuedo-expected tpt-disconnect
-                    # debug_filter=lambda exc: (
-                    #     type (exc) not in {
-                    #         TransportClosed,
-                    #     }
-                    # ),
                 )
                 if not entered_debug:
                     # if we prolly should have entered the REPL but
@@ -438,7 +433,7 @@ async def _errors_relayed_via_ipc(
             # cancel scope will not have been inserted yet
             if is_rpc:
                 log.warning(
-                    'RPC task likely errored or cancelled before start?\n'
+                    'RPC task likely crashed or cancelled before start?\n'
                     f'|_{ctx._task}\n'
                     f'  >> {ctx.repr_rpc}\n'
                 )
@@ -694,22 +689,6 @@ async def _invoke(
                     f'{pretty_struct.pformat(return_msg)}\n'
                 )
                 await chan.send(return_msg)
-                # ?TODO, remove the below since .send() already
-                # doesn't raise on tpt-closed?
-                # try:
-                #     await chan.send(return_msg)
-                # except TransportClosed:
-                #     log.exception(
-                #         f"Failed send final result to 'parent'-side of IPC-ctx!\n"
-                #         f'\n'
-                #         f'{chan}\n'
-                #         f'Channel already disconnected ??\n'
-                #         f'\n'
-                #         f'{pretty_struct.pformat(return_msg)}'
-                #     )
-                #     # ?TODO? will this ever be true though?
-                #     if chan.connected():
-                #         raise
 
             # NOTE: this happens IFF `ctx._scope.cancel()` is
             # called by any of,