MIL-013: Debian container and Windows Sandbox checks

A Debian image (python:3.13-slim-bookworm with Xvfb and GNOME's window
manager) runs the linters, the whole test suite, the screenshots and the
smoke test of a PyInstaller Linux binary and of the source program, so no
window opens on the development machine. The screenshot tool works on
Linux, a smoke driver presses the known button with the virtual mouse, and
Windows Sandbox scripts are written (not run, they open a window on the
host). README and the wiki Install pages describe it. Review records
RC-077 (Python) and RC-078 (shell).

Task: MIL-013#2
Task: MIL-013#3
Task: MIL-013#4
Task: MIL-013#5
Task: MIL-013#6
Task: MIL-013#7
Task: MIL-013#9
Task: MIL-013#10

tests/unit/test_smoke_driver.py

@@ -0,0 +1,122 @@
+"""Tests of the smoke driver tool.
+
+@file test_smoke_driver.py
+@brief Checks the pure helpers and the run loop of tools/docker/smoke_driver.py
+with a fake xdotool and a fake program.
+"""
+
+import importlib.util
+import json
+import sys
+from collections.abc import Sequence
+from pathlib import Path
+from types import ModuleType
+
+import pytest
+
+_TOOL_PATH = (
+    Path(__file__).resolve().parents[2] / "tools" / "docker" / "smoke_driver.py"
+)
+_GEOMETRY = "WINDOW=7\nX=0\nY=0\nWIDTH=900\nHEIGHT=800\nSCREEN=0\n"
+
+
+def _load_tool() -> ModuleType:
+    spec = importlib.util.spec_from_file_location("smoke_driver", _TOOL_PATH)
+    assert spec is not None
+    assert spec.loader is not None
+    module = importlib.util.module_from_spec(spec)
+    # dataclasses looks the module up by name while the class is built
+    sys.modules[spec.name] = module
+    spec.loader.exec_module(module)
+    return module
+
+
+class _FakeProgram:
+    def __init__(self) -> None:
+        self.stopped = False
+
+    def stop(self) -> None:
+        self.stopped = True
+
+
+class _FakeSystem:
+    """Fake xdotool and program; a click writes the progress file."""
+
+    def __init__(self, has_window: bool, writes_progress: bool) -> None:
+        self.has_window = has_window
+        self.writes_progress = writes_progress
+        self.program = _FakeProgram()
+        self.data_dir: Path | None = None
+
+    def start(self, command: Sequence[str]) -> _FakeProgram:
+        self.data_dir = Path(command[command.index("--data-dir") + 1])
+        return self.program
+
+    def run(self, args: Sequence[str]) -> str:
+        if args[1] == "search":
+            return "7\n" if self.has_window else ""
+        if args[1] == "getwindowgeometry":
+            return _GEOMETRY
+        if args[1] == "mousemove" and self.writes_progress:
+            assert self.data_dir is not None
+            progress = self.data_dir / "words_to_learn.csv"
+            progress.write_text("ms;da\nw1;t1\nw2;t2\n", encoding="utf-8")
+        return ""
+
+
+def test_known_button_point_is_101_above_bottom() -> None:
+    assert _load_tool().known_button_point(900, 800) == (650, 699)
+
+
+def test_words_file_text_has_header_and_cards() -> None:
+    assert _load_tool().words_file_text(2) == "ms;da\nw1;t1\nw2;t2\n"
+
+
+def test_parse_geometry_reads_width_and_height() -> None:
+    assert _load_tool().parse_geometry(_GEOMETRY) == (900, 800)
+
+
+def test_parse_geometry_fails_without_size() -> None:
+    with pytest.raises(ValueError):
+        _load_tool().parse_geometry("X=0\n")
+
+
+def test_progress_ok_needs_exactly_one_card_less() -> None:
+    tool = _load_tool()
+    assert tool.progress_ok(3, 3)
+    assert not tool.progress_ok(4, 3)
+    assert not tool.progress_ok(0, 3)
+
+
+def test_main_returns_zero_when_click_saves_progress(
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    system = _FakeSystem(has_window=True, writes_progress=True)
+    code = _load_tool().main(
+        ["--repeat", "2", "--words", "3", "--command", "prog", "-m", "x"],
+        run=system.run,
+        start=system.start,
+        sleep=lambda _: None,
+    )
+    lines = [json.loads(x) for x in capsys.readouterr().out.splitlines()]
+    assert code == 0
+    assert lines[0]["ok"] is True
+    assert lines[0]["clicked"] == [650, 699]
+    assert lines[-1] == {"runs": 2, "passed": 2}
+    assert system.program.stopped
+
+
+def test_main_fails_when_no_window_appears(
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    system = _FakeSystem(has_window=False, writes_progress=False)
+    code = _load_tool().main(
+        ["--repeat", "1", "--timeout", "1", "--command", "prog"],
+        run=system.run,
+        start=system.start,
+        sleep=lambda _: None,
+    )
+    first = json.loads(capsys.readouterr().out.splitlines()[0])
+    assert code == 1
+    assert first["window"] is False
+    assert system.program.stopped