fix: handle disconnected launcher output

Makefile

@@ -8,6 +8,7 @@ install:
 
 test:
 	python -c 'import aw_qt'
+	python -m pytest tests/test_main.py
 
 test-integration:
 	python ./tests/integration_tests.py --no-modules

aw_qt/main.py

@@ -4,6 +4,7 @@
 import subprocess
 import platform
 import signal
+import select
 import threading
 from typing import Optional
 from time import sleep
@@ -26,6 +27,32 @@
 logger = logging.getLogger(__name__)
 
 
+def _ensure_output_streams() -> None:
+    # Desktop launchers can leave stdout/stderr on a disconnected terminal or pipe.
+    # Repair unusable descriptors before either aw-qt or its modules write.
+    for fd in (1, 2):
+        unusable = False
+        try:
+            os.write(fd, b"")
+            if sys.platform != "win32":
+                poller = select.poll()
+                # A zero event mask still reports errors and hangups.
+                poller.register(fd, 0)
+                unusable = bool(poller.poll(0))
+        except OSError:
+            unusable = True
+        if not unusable:
+            continue
+        devnull = os.open(os.devnull, os.O_WRONLY)
+        if devnull == fd:
+            os.set_inheritable(fd, True)
+        else:
+            try:
+                os.dup2(devnull, fd)
+            finally:
+                os.close(devnull)
+
+
 def _acquire_single_instance_lock(profile: str) -> QLockFile:
     """Ensure only one instance of aw-qt runs at a time.
 
@@ -92,6 +119,8 @@ def main(
     no_gui: bool,
     interactive_cli: bool,
 ) -> None:
+    _ensure_output_streams()
+
     # Since the .app can crash when started from Finder for unknown reasons, we send a syslog message here to make debugging easier.
     if platform.system() == "Darwin":
         subprocess.call("syslog -s 'aw-qt started'", shell=True)

pyproject.toml

@@ -32,6 +32,7 @@ PyQt6 = "6.5.3"
 PyQt6-Qt6 = "6.5.3"
 
 [tool.poetry.dev-dependencies]
+pytest = "^8.3.5"
 mypy = "*"
 PyQt6-stubs = { git = "https://github.com/TilmanK/PyQt6-stubs", rev = "main" }
 flake8 = "*"

tests/test_main.py

@@ -1,6 +1,9 @@
-"""Startup must use the effective CLI server selection, not the saved list."""
+"""Tests for the launcher entry point."""
 
 import importlib
+import os
+import subprocess
+import sys
 from unittest.mock import MagicMock, patch
 
 import pytest
@@ -81,3 +84,97 @@ def test_cli_server_free_override_preserves_configured_port(
     )
     assert run.call_args.kwargs["port"] == 5678
     manager.return_value.autostart_notify_if_enabled.assert_not_called()
+
+
+@pytest.mark.skipif(sys.platform == "win32", reason="requires POSIX file descriptors")
+@pytest.mark.parametrize(
+    "broken_output, broken_fd",
+    [("healthy", 0), ("terminal", 1), ("terminal", 2), ("pipe", 1), ("pipe", 2)],
+    ids=["healthy", "terminal-stdout", "terminal-stderr", "pipe-stdout", "pipe-stderr"],
+)
+def test_startup_preserves_modules_and_gui_actions(tmp_path, broken_output, broken_fd):
+    executable = tmp_path / "aw-test-output"
+    ready = tmp_path / "ready"
+    executable.write_text(
+        f"#!{sys.executable}\n"
+        "import os, signal\n"
+        "from pathlib import Path\n"
+        "os.write(1, b'child stdout\\n')\n"
+        "os.write(2, b'child stderr\\n')\n"
+        f"Path({str(ready)!r}).touch()\n"
+        "signal.pause()\n"
+    )
+    executable.chmod(0o755)
+
+    launcher = """
+import os
+import pty
+import sys
+import time
+from pathlib import Path
+from unittest.mock import patch
+import platformdirs
+from aw_qt import main, trayicon
+
+root = Path(sys.argv[1])
+broken_fd = int(sys.argv[2])
+broken_output = sys.argv[3]
+if broken_output == "terminal":
+    master, slave = pty.openpty()
+    os.close(master)
+    os.dup2(slave, broken_fd)
+    os.close(slave)
+elif broken_output == "pipe":
+    reader, writer = os.pipe()
+    os.close(reader)
+    os.dup2(writer, broken_fd)
+    os.close(writer)
+# A real terminal makes parent stdout line-buffered, so GUI action prints
+# must complete before their browser and shutdown effects can happen.
+sys.stdout.reconfigure(line_buffering=True)
+
+# XDG variables do not isolate macOS application directories.
+for name, kind in (
+    ("user_config_dir", "config"), ("user_data_dir", "data"),
+    ("user_cache_dir", "cache"), ("user_log_dir", "logs"),
+):
+    setattr(platformdirs, name, lambda appname, *args, kind=kind, **kwargs: str(root / kind / appname))
+platformdirs.user_cache_path = lambda appname, *args, **kwargs: root / "cache" / appname
+
+def exercise_gui_actions(manager, **kwargs):
+    module = next(m for m in manager.modules if m.name == "aw-test-output")
+    try:
+        deadline = time.monotonic() + 5
+        while not (root / "ready").exists():
+            assert module.is_alive(), "child failed before completing its writes"
+            assert time.monotonic() < deadline, "child did not become ready"
+            time.sleep(0.01)
+        with patch.object(trayicon, "open_url") as open_url, patch.object(trayicon.QApplication, "quit") as quit_app:
+            trayicon.open_webui("http://example.invalid")
+            open_url.assert_called_once_with("http://example.invalid")
+            trayicon.exit(manager)
+            quit_app.assert_called_once_with()
+            assert not module.is_alive()
+        return 0
+    finally:
+        manager.stop_all()
+
+trayicon.run = exercise_gui_actions
+main(["--profile", "output-test", "--autostart-modules=aw-test-output"])
+"""
+    env = dict(os.environ, PATH=str(tmp_path) + os.pathsep + os.environ["PATH"])
+    result = subprocess.run(
+        [sys.executable, "-c", launcher, str(tmp_path), str(broken_fd), broken_output],
+        env=env,
+        capture_output=True,
+        text=True,
+        timeout=15,
+    )
+
+    assert result.returncode == 0, result.stderr
+    if broken_fd != 1:
+        assert "child stdout\n" in result.stdout
+        assert "Opening dashboard\n" in result.stdout
+        assert "Shutdown initiated, stopping all services...\n" in result.stdout
+    if broken_fd != 2:
+        assert "child stderr\n" in result.stderr