feat(video_analysis): download_video.py with TDD (5 tests)

tests/test_video_analysis_download_video.py

@@ -0,0 +1,50 @@
+from __future__ import annotations
+
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+from scripts.video_analysis.download_video import (
+ build_ydl_args,
+ download_video,
+ validate_output_path,
+)
+
+
+def test_validate_output_path_creates_parent(tmp_path: Path) -> None:
+ out = tmp_path / "subdir" / "video.mp4"
+ result = validate_output_path(out)
+ assert result.is_ok()
+ assert out.parent.exists()
+
+
+def test_validate_output_path_rejects_existing_dir(tmp_path: Path) -> None:
+ out = tmp_path / "existing_dir"
+ out.mkdir()
+ result = validate_output_path(out)
+ assert result.is_err()
+
+
+def test_build_ydl_args_basic(tmp_path: Path) -> None:
+ out = tmp_path / "v.mp4"
+ args = build_ydl_args("https://youtu.be/VID", out)
+ assert "--output" in args
+ assert str(out) in args
+ assert "https://youtu.be/VID" in args
+
+
+def test_download_video_success(tmp_path: Path) -> None:
+ out = tmp_path / "video.mp4"
+ out.write_bytes(b"fake-mp4-content")
+ with patch("subprocess.run") as mock_run:
+  mock_run.return_value = MagicMock(returncode=0, stdout="", stderr="")
+  result = download_video("https://youtu.be/VID", out)
+  assert result.is_ok()
+  assert (tmp_path / "video.log").exists()
+
+
+def test_download_video_failure(tmp_path: Path) -> None:
+ out = tmp_path / "video.mp4"
+ with patch("subprocess.run") as mock_run:
+  mock_run.return_value = MagicMock(returncode=1, stdout="", stderr="ERROR: video unavailable")
+  result = download_video("https://youtu.be/VID", out)
+  assert result.is_err()