Add more tests for PlaylistDownloader functionality

tests/test_fetch_videos.py

@@ -0,0 +1,48 @@
+import json
+import subprocess
+from types import SimpleNamespace
+
+from ytplaylist.downloader import PlaylistDownloader
+from tests.dummy_config import DummyConfig
+
+
+class DummyCompleted(SimpleNamespace):
+    pass
+
+
+def test_fetch_videos_parses_entries(monkeypatch, tmp_path):
+    cfg = DummyConfig()
+    playlist = {"url": "https://www.youtube.com/playlist?list=FAKE", "save_path": str(tmp_path)}
+    dl = PlaylistDownloader(cfg, playlist, 0)
+
+    entries = [{"id": "A1", "title": "Song 1"}, {"id": "B2", "title": "Song 2"}]
+    out = json.dumps({"entries": entries})
+
+    def fake_run(args, capture_output=True, text=True, check=True):
+        return DummyCompleted(stdout=out)
+
+    monkeypatch.setattr(subprocess, "run", fake_run)
+
+    res = dl.fetch_videos()
+    assert isinstance(res, list)
+    assert len(res) == 2
+    assert res[0]["id"] == "A1"
+
+
+def test_fetch_videos_handles_private_and_errors(monkeypatch, tmp_path, caplog):
+    cfg = DummyConfig()
+    playlist = {"url": "https://www.youtube.com/playlist?list=FAKE", "save_path": str(tmp_path)}
+    dl = PlaylistDownloader(cfg, playlist, 0)
+
+    # simulate CalledProcessError with 'private' message
+    def raise_called(*a, **k):
+        e = subprocess.CalledProcessError(1, cmd=a[0])
+        e.stderr = "This playlist is private"
+        raise e
+
+    monkeypatch.setattr(subprocess, "run", raise_called)
+
+    caplog.set_level("WARNING")
+    res = dl.fetch_videos()
+    assert res == []
+    assert dl.skip is True