Add game data capture vertical slice

tools/game-data-capture/tests/integration/test_clipboard_watch.py

@@ -0,0 +1,42 @@
+from __future__ import annotations
+
+import subprocess
+import sys
+import time
+from pathlib import Path
+
+import pytest
+
+from game_data_capture.ingest.clipboard import ClipboardIntake, WatchConfig
+
+
+def test_shutdown_reaps_real_child_process_group(
+    tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    child: subprocess.Popen[bytes] | None = None
+    real_popen = subprocess.Popen
+
+    def fake_popen(args: list[str], **kwargs: object) -> subprocess.Popen[bytes]:
+        nonlocal child
+        assert args[0] == "wl-paste" and kwargs["shell"] is False
+        child = real_popen(
+            [sys.executable, "-c", "import time; time.sleep(30)"],
+            stdin=subprocess.DEVNULL,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.DEVNULL,
+            start_new_session=True,
+        )
+        return child
+
+    monkeypatch.setattr(subprocess, "Popen", fake_popen)
+    intake = ClipboardIntake(
+        WatchConfig((tmp_path / "spool").resolve(), 100, 1, "v1", 1, 0.01, 0.2)
+    )
+    intake.arm()
+    assert child is not None and child.poll() is None
+    intake.shutdown()
+    for _ in range(20):
+        if child.poll() is not None:
+            break
+        time.sleep(0.01)
+    assert child.poll() is not None