Stop sandbox export children on SIGINT during startup

marimo/_cli/export/_common.py

@@ -71,11 +71,19 @@ def terminate(signum: int, _frame: object) -> None:
 
     try:
         if threading.current_thread() is threading.main_thread():
-            for name in ("SIGTERM", "SIGHUP"):
+            for name in ("SIGINT", "SIGTERM", "SIGHUP"):
                 signum = getattr(signal, name, None)
+                # Python 3.10 raises KeyboardInterrupt synchronously; defer it
+                # past Popen just like termination. Python 3.11+ asyncio.run
+                # already installs a cancelling handler, which we preserve.
+                default_handler = (
+                    signal.default_int_handler
+                    if name == "SIGINT"
+                    else signal.SIG_DFL
+                )
                 if (
                     signum is not None
-                    and signal.getsignal(signum) == signal.SIG_DFL
+                    and signal.getsignal(signum) == default_handler
                 ):
                     previous[signum] = signal.signal(signum, terminate)
         yield
@@ -84,6 +92,8 @@ def terminate(signum: int, _frame: object) -> None:
         for signum, handler in previous.items():
             signal.signal(signum, handler)
         # The command may finish before queued cancellation is delivered.
+        if termination_signal == signal.SIGINT:
+            raise KeyboardInterrupt from None
         if termination_signal is not None:
             raise SystemExit(128 + termination_signal) from None
 

tests/_cli/test_export_subprocess.py

@@ -250,7 +250,7 @@ async def interrupted_cleanup(
 
 
 @pytest.mark.skipif(os.name == "nt", reason="POSIX termination signals")
-@pytest.mark.parametrize("signal_name", ["SIGTERM", "SIGHUP"])
+@pytest.mark.parametrize("signal_name", ["SIGINT", "SIGTERM", "SIGHUP"])
 def test_export_termination_during_process_creation(signal_name: str) -> None:
     code = """
 import asyncio, json, signal, subprocess, sys
@@ -272,9 +272,16 @@ async def main():
     with _export_termination_signals():
         await run_command([sys.executable, '-c', 'import time; time.sleep(30)'])
 
+loop = asyncio.new_event_loop()
 try:
-    asyncio.run(main())
+    # Do not use asyncio.run here. On Python 3.11+, Runner installs its own
+    # SIGINT handler, which deliberately bypasses the default-handler branch
+    # that protects Python 3.10 from an interrupt during Popen.
+    loop.run_until_complete(main())
+except KeyboardInterrupt:
+    sys.exit(1)
 finally:
+    loop.close()
     print(json.dumps([process.poll() is None for process in processes]))
     for process in processes:
         if process.poll() is None:
@@ -287,9 +294,9 @@ async def main():
         text=True,
         timeout=10,
     )
-    assert completed.returncode == 128 + getattr(signal, signal_name), (
-        completed.stderr
-    )
+    assert completed.returncode == (
+        1 if signal_name == "SIGINT" else 128 + getattr(signal, signal_name)
+    ), completed.stderr
     assert json.loads(completed.stdout) == [False]