Update.

tests/bashrc.py

@@ -43,6 +43,20 @@ async def _drain_forever(proc):
         pass
 
 
+def _kill_mplex_server(tmp_home):
+    """The wrapped shell lives in a detached mplex server that outlives the test's client
+    process; stop it, or it keeps its sockets open inside the directory being deleted."""
+    import subprocess
+    env = dict(os.environ, TAI_HOME=os.path.join(tmp_home, ".tai"))
+    for name in (tai.PLEXER_ACTIVE_ENV, tai.PLEXER_SOCKET_ENV, tai.PLEXER_PANE_ENV, "TMUX"):
+        env.pop(name, None)
+    try:
+        subprocess.run([sys.executable, str(Path(tai.__file__).resolve()), "--mplex", "kill-server"], env=env,
+                       stdin=subprocess.DEVNULL, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL, timeout=15)
+    except (OSError, subprocess.SubprocessError):
+        pass
+
+
 class _BashrcHookTestBase(TestCase):
     """Shared fixture for every test that installs the real plexer hook into
     a real .bashrc: a throwaway $HOME, the real tai.py binary copied into
@@ -94,6 +108,7 @@ class _BashrcHookTestBase(TestCase):
         if self._drain_task is not None:
             self._drain_task.cancel()
         if self.tmp_home is not None:
+            _kill_mplex_server(self.tmp_home)
             shutil.rmtree(self.tmp_home, ignore_errors=True)
 
 
@@ -151,6 +166,7 @@ class _ShellPlexerHookTestBase(TestCase):
         if self._drain_task is not None:
             self._drain_task.cancel()
         if self.tmp_home is not None:
+            _kill_mplex_server(self.tmp_home)
             shutil.rmtree(self.tmp_home, ignore_errors=True)